Sponsorships

1

Contents ................................................................................................................................................ 1

Welcome Remarks ............................................................................................................................... 3

About ITB International Geothermal Workshop ............................................................................ 4

Background and Objectives ................................................................................................................ 4

Organizing and Technical Committee ................................................................................................. 5

Workshop Venue Map ........................................................................................................................ 6

ITB Campus Map ............................................................................................................................. 6

Room Layout ................................................................................................................................... 7

Programme

Pre-Workshop Courses ....................................................................................................................... 9

Pre-Workshop Course 1 (ISOR, QED, SATE PTE LTD) .................................................................... 11

Pre-Workshop Course 2 (GEOCAP) ............................................................................................... 12

Pre-Workshop Course 3 (ITB) ....................................................................................................... 13

Workshop ............................................................................................................................................ 15

Plenary Session ................................................................................................................................. 17

Mid-Workshop Course ...................................................................................................................... 18

Parallel Technical Session ................................................................................................................. 19

Post-Workshop ................................................................................................................................... 27

Field Trip............................................................................................................................................ 29

Field Camp ......................................................................................................................................... 30

Abstract ............................................................................................................................................... 33

Content

2

3

Welcome Remarks

Dear Colleague,

Following the success of the last four workshop, Geothermal Technology Master Program of

Institut Teknologi Bandung (ITB) is planning to organize the Fifth Annual ITB International

Geothermal Workshop 2016 (5th ITB IGW 2016). This event is an immediate response from

academic, government, and industrial geothermal community by unifying forces to

accelerate geothermal development in Indonesia. This year theme “The New Era: Initiatives,

Strategies, Opportunities, and Challenges toward Geothermal Development in Indonesia”

will bring new information about current research, innovation, and results of exploration

and engineering activities regarding geothermal developments. Particularly, this coming

event will focus on all aspect and issues as the impact of new geothermal regulation which

has been implemented last year.

This event, which includes pre-workshop courses and trainings, plenary sessions, technical

paper presentations, mid-workshop courses and geothermal field camp and field trip, will be

held at Campus Centre (East Side) and Gallery Room in Campus Centre (East Side) in ITB

Campus, Bandung, Macrh 28th-April 2nd, 2016. The panel discussion and paper presentation

event will be hosted by distinguished speakers which cover the following topics:

1. Education and Research

2. Business and Regulation

3. Exploration

4. Exploitation

5. Environmental aspects

They will speak about the current innovation and creativity on geothermal exploration,

exploitation and development not only for the geothermal resources but also for the human

resources that support the acceleration geothermal development.

We invite you to join our informative and exciting program in this 5th workshop which

includes pre-workshop courses and trainings, plenary sessions, technical paper

presentations, mid-workshop courses and geothermal field camp and field trip.

Sincerely,

Suryantini

5th ITB International Geothermal Workshop Organizing Committee

4

About ITB International Geothermal Workshop

Background

The 5th Annual ITB International Geothermal Workshop 2016 is special event since it is the

5th anniversary Workshop and it will be different from the previous event. This year event

will focus more on educating geothermal community with more courses and invited speaker

from various expertise. The course such as “Environmental Assessment, Risk Analysis, and

Project Decision” by GEOCAP, “Geothermal Exploration” course by IAGI and invited speaker

from Iceland Geo-survey (ISOR), and many more will share their knowledge on developing

geothermal in their country and their other overseas projects. The other purpose of this

event is to discuss the latest condition of geothermal energy industry in Indonesia after the

approval of new regulation of geothermal energy UU No 21 Tahun 2014.

Objective

The workshop will have the following exclusive objectives:

Educate the community about the geothermal energy from exploration, exploitation,

environmental aspects and regulation.

Discuss the latest condition of geothermal energy in Indonesia after the approval of

new regulation of geothermal energy UU No 21 Tahun 2014.

To draw attention from scientist, engineers, including academia, industrial

stakeholders, and also geothermal leaders about the initiatives, strategies,

opportunities, and challenges toward geothermal development in Indonesia.

5

Organizing and Technical Commitee

Steering Committee Nenny Miryani Saptadji and Staff of Geothermal Technology Study Program, FTTM – ITB Antonie de Wilde (SATE PTE LTD-Singapore)

Chairman Suryantini

Vice Chairman Ali Fahrurrozie, Akhmad Kunio Pratopo

Secretary General Angga Alfandi Ahmad, Evanda Eko Putra, Fitri Oktaviani Purwaningsih

Treasurer Rizki Trisna Hutami, Betseba br Sibarani

Creative Team Hibban Hammka, Ali Fahrurozie, Hendro Wibowo

Sponsorship, Publications & Promotion

Prihadi Soemintadiredja, Fikri Adam Dermawan, Rully Abdul Malik, Fransiscus Xaverius Guwowijoyo, Damar Nandawardhana, Gugun Abdurrahman, Hutra Guswinanda, Andhika Arief Rachman

Pre – Workshop Course

Dimas Taha Maulana, Allen Haryanto Lukman, Fikri Adam Dermawan, Famelia Nurlaela

Technical Session & Planning

Asep Saepuloh, Suryantini, Nurita Putri H, Juni Yesy Sianipar, Setya Drana Harry Putra, Anggie Rengganis, Agastyo Nugroho, Heru Berian Pratama

Field Trip & Field Camp

Qodri Syahrur Ramadhan, Silvester Dimas Sanjaya, Mahesa Pradana, Ratih Nurruhliati

Exhibition Mahesa Pradana, Rully Tri Abdul Malik

Reviewer Team

Suryantini, Hendro Wibowo, Sutopo, Zuher Syihab, Prihadi Darminto, Prihadi Soemintadiredja, Jooened Hendrasakti, Fiorenza Deon (GFZ), Chris Hecker (Twente University), Hendra Grandis, Rachmat Sule, Nenny Miryani Saptadji, Antonie de Wilde, Joe Iovenitti, Erwin Dasapta

Logistic Qodri Syahrur Ramadhan, Welly Todheus, Fhandy Pandey

6

Workshop Venue Map

ITB Campus Map

7

Workshop Venue Map

Room Layout

Parallel Technical Session Venue Map

Room Layout

8

9

PROGRAMME

Pre – Workshop Courses

10

11

Pre-Workshop Course 1

Monday-Tuesday, March 28-29th 2016

Geothermal Drilling and Negotiating Integrated Drilling Services Contract (ISOR, QED, SATE PTE LTD)

Venue Auditorium Campus Center

Lecturers Antonie de Wilde (SATE), Sverrir Thorhallsson and Dadi Thorbjornsson (ISOR - Iceland), Renato Escalante (QED)

Day 1 :

08.00-10.00 Overview of various types of geothermal systems. Implication on drilling approach and utilization Exploration drilling vs. production drilling

ISOR

10.00-10.30 BREAK

10.30-11.45 Geothermal well designs, large holes vs. slim holes ISOR

11.45-12.30 LUNCH

12.30-13.30 Selection of drilling equipment Selection of drilling fluids and cementing procedures

ISOR

13.30-15.00 Chemical sampling and interpretation Environmental impacts of drilling and testing

ISOR

15.00-15.30 BREAK

15.30-17.00 Monitoring and use of rig data to improve drilling efficiency and solve drilling problems

ISOR

Day 2 :

08.00-10.00 Preparation of the “Drilling Program” document ISOR-SATE

10.00-10.30 BREAK

10.30-11.45 Drilling contracts SATE

11.45-12.30 LUNCH

12.30-13.30 Mud logging ISOR

13.30-15.00 Well logging and well completion tests Well testing Flow rate measurements (Russel James and TFT)

ISOR

15.00-15.30 BREAK -

15.30-17.30 Case Study: The Experience of drilling SH1 and SH2 in Mindoro QED

17.30-18.00 Closing

12

Pre-Workshop Course 2

Monday-Tuesday, March 28-29th 2016

Environmental Assessment, Risk Analysis, and Project Decision (GEOCAP)

Venue Meeting Room 5 and 6, 3rd Floor, East Campus Center

Lecturers Christian Bos (TNO, NL), Kees van den Ende (DNV GL), Rianne ‘t Hoen (DNV GL), Triarko Nurlambang (UI), Ali Ashat (ITB)

Day 1 :

08.00-10.00 The energy landscape - Paris COP21 - Energy transition strategies - Renewable energy schemes

GEOCAP

10.00-10.30 Break

10.30-11.45 Outlook Indonesian energy mix - Roadmap development - Geothermal policy framework - Early experience/ lessons learned

GEOCAP

11.45-12.30 LUNCH

12.30-13.30 Social License to Operate (Strategic environmental assessment) - Environmental aspects (flora, fauna, soil, landscape, humans, cultural heritages)

GEOCAP

13.30-15.00 SEA criteria - Consideration alternatives - Methods of comparison (Leopold matrix) - Significant effect and mitigation measures

GEOCAP

15.00-15.30 Break

15.30-17.00 Working with SEA – exercises geothermal GEOCAP

Day 2 :

08.00-10.00

Geothermal plant project phases and decision making - Decision moments - Decision criteria - Bankability criteria

GEOCAP

10.00-10.30 Break

10.30-11.45 Strategies for decision making - Decision strategies and evaluation criteria - Methodologies and processes - Decision tree analysis - Multi-criteria analysis

GEOCAP

11.45-12.30 LUNCH

12.30-13.30 Risk analysis methods - Sensitivity analysis

GEOCAP

13

Pre-Workshop Course 3

Monday-Tuesday, March 28-29th 2016

13.30-15.00

Risk mitigation - Real option - Costs of knowledge - Portfolio management

GEOCAP

15.00-15.30 Break

15.30-17.30 Decision making with confidence –exercises risk analyses and decision making geothermal

GEOCAP

17.30-18.00 Closing

Geothermal for Everyone (ITB Geothermal Study Program)

Venue Meeting room 4, 3rd Floor, East Campus Center

Lecturers Suryantini, Nenny Miryani Saptadji, Ali Ashat

DAY 1

08.00-10.00 Geothermal System; Type, Worldwide Occurrence and Utilization

10.00-10.30 Coffee Break

10.30-12.00 Geothermal Manifestation and Geothermal Exploration

12.00-13.00 LUNCH

13.00-15.00 Engineering and Exploitation of Geothermal Energy

15.00-15.30 Coffee Break

15.30-17.00 Economic and Environmental Issue of Geothermal Energy Utilization

14

15

PROGRAMME

Workshop

16

17

Plenary and Technical Sessions

Wednesday-Thursday, March 30-31st 2016

PLENARY SESSION

Wednesday, March 30th 2016

PLENARY SESSION

Venue East Hall (Aula Timur) ITB Campus, Jalan Ganesha 10, Bandung.

Opening and Keynote Speaker

09.00-09.05 Welcoming remark from the Chairman of IIGW 2016

Suryantini

National Anthem : Indonesia Raya

09.05-09.15 Opening Speech of the IIGW 2016 by the Dean of Faculty of Mining and Petrouleum Engineering

Sri Widiyantoro /Dean FTTM

09.15-09.45 Keynote Speech-1: Geothermal Development Plan within National Energy Council Road Map; Will it be successful?

Abadi Poernomo / Chairman of Indonesian Geothermal Association (INAGA), Member of National Energy Council (DEN).

09.45-10.15 Keynote Speech-2: Geothermal Law Breakthrough; Latest Condition and Future Impact

Yunus Saefulhak /Director of Directorate of Geothermal-Ministry of Energy and Mineral Resources

COFFEE BREAK

PLENARY SESSION 1 Overcoming the Stagnancy in Geothermal Development

10.30-11.00

The Role of National Exploration Committee (KEN) in Accelerating Geothermal Development in Indonesia and its implication to Geothermal Industry, Government and Academic Society.

Andang Bachtiar / Chairman of National Exploration Committee (KEN)- Ministry of Energy and Mineral Resources

11.00-11.30 PGE strategy to support Government of Indonesia goal in 2025

Ali Mundakir/ Director of Operation, PT PERTAMINA GEOTHERMAL ENERGY

11.30-12.30 OPENING OF LIMITED EXHIBITION, PHOTO CONTEST and POSTER SESSION

LUNCH BREAK

18

PLENARY SESSION 2 Lesson Learned from Geothermal Development

13.15-13.45 Lesson learns from re-negotiating electric price Peter Wijaya / VP Star Energy Geothermal

13.45-14.15 Learning from more than 60 years of Geothermal History-the benefits to Today’s Developers

Alex Smillie (Tawau Green Energy Malaysia)

COFFEE BREAK

Mid-Workshop Course

Thursday, March 31th 2016

PLENARY SESSION 3 Expanding the role of national human resources beyond the country

15.00-15.30 GEOCAP plan for increasing the role of Indonesian Human Resources in International Geothermal Industry

Sanusi Satar (GEOCAP)

15.30-16.00

IAGI (Indonesian Association of Geologist) plan to advance and expand geothermalist skill and knowledge to face MEA (ASEAN Economic Community)

Sukmandaru Prihatmoko (Chairman IAGI)

16.00-16.30 SATREPS: Japanese Academic Institution strategy for strengthening geothermal community knowledge and skill in Indonesia

Sudarto Notosiswojo (ITB)-Katsuaki Koike (Kyoto University)

16.30-17.00 Gathering and Networking MC: Sanusi Satar-Nenny Saptadji

17.00-18.30 Celebration of the 5th ITB International Geothermal Workshop: Speech, Dance and Music Performance Videos

18.30-20.00 GALA DINNER

Geothermal Exploration (IAGI-Ikatan Ahli Geologi Indonesia/Indonesian Geologist Association)

Venue Meeting room 3, 3rd Floor, East Campus Center

Lecturers Imam Baru Raharjo (PGE), Basuki Arif Wijaya (Independent Consultant, Former Chevron Geochemist), Arief Sunu (MEDCO)

Time 13.30 – 15.30 (2 hrs)

19

Parallel Technical Session

Information

Power Point File Check-In

For you who have not yet sent us your power point file via email in advance, you will be

asked to give your powerpoint file on first day of workshop (March 30). Please visit the

power point check in desk in East Hall ITB on March 30.

Time Allowance

The time allowance for each presentation in Technical Session is 15 minutes followed with a 5 minutes of Questions and Answers Session, which means that the total time you will have is 20 minutes. The speakers will be announced when the time lapse. First announcement: You will have 5 minutes to finish your presentation (10 minutes passed) Second announcement: Your time is up (15 minutes passed)

Note for the Speakers:

Please be present in the room where you will give presentation 15 minutes before your

session starts.

INVITED SPEAKER:

Speakers Time

ISOR Auditorium ( 09.30-10.10)

GEOCAP Auditorium ( 10.30-12.10)

SATREPS Auditorium ( 13.30-15.10)

Andri Dian Nugraha (ITB) Room 4 (09.30-10.10)

Bonar Tua Halomoan Marbun (ITB) Room 4 (10.30-11.10)

Tobias Fischer (New Mexico Univ. USA) Room 5 (09.30-10.10)

Pri Utami (UGM) Room 5 (13.30-14.10)

Wahyu Sri Gutomo (ITB) Room 6 (09.30-10.10)

Clare Baxter (LEAPFROG) Room 6 (13.30-14.10)

20

21

Parallel Technical Session

Thursday, March 31st 2016 VENUE: EAST CAMPUS CENTER

TIME AUDITORIUM ROOM 4 ROOM 5 ROOM 6

SESSION ENGINEERING

Chairperson: Ali Ashat & Waldy Afuar

GEOPHYSICS Chairperson: Prihadi Sumintadireja & Dian

Darisma

GEOLOGY Chairperson: Arief Susanto & M.

Nurwahyudi Yulianto

GEOPHYSICS Chairperson: Hendra Grandis &

Angga Bakti P.

08:10 – 08:30

Numerical Simulation for Natural State of Two-Phase Liquid Dominated Geothermal

Reservoir with Steam Cap Above Brine Reservoir (Heru Berian Pratama and Nenny

Saptadji-Geothermal ITB) [042]

08:30 – 08:50

Performance Prediction of Two-Phase Geothermal Reservoir Using Lumped

Parameter Model (Famelia Nurlaela and Sutopo-Geothermal ITB)

[121]

Resistivity Method for Hydrothermal System Analyze in Way Ratai Geothermal Field

(Widia A. and Bagas S.-UNILA) [097]

Volcanostratigraphy for Supporting Geothermal Exploration (Sutikno Bronto,

Juni Yesy Sianipar, and Akhmad Kunio Pratopo,-PSG and Geothermal ITB) [090]

Gravity Modelling and Second Vertical Derivative Calculation to Analysis Subsurface Structure at Wayratai

Geothermal Prospect Area, Lampung (Taufiq-Univ. Lampung) [091]

08:50 – 09:10

Resource Management using Numerical Modeling and Apparent Productivity Index

(William L. Osborn, Dennis Kaspereit, William Rickard, Mary Mann, Magdalena

Perez-Geothermal Resource Group, Momotombo Power Company) [115]

Geophysical Exploration For Geothermal Low Enthalpy Resources In Ungaran

Regency, Central Java (Udi Harmoko, Hiska Anggit, Gatot Yulianto, Sugeng Widada, Yusud D.-UNDIP, Semarang

State Polytecnic) [095]

Volcanolostratigraphic Study in Constructing Volcano Chronology and its

Implication for Geothermal Resource Estimation; Case Study Mount Sawal,

West Java (Fikri Adam Dermawan, Hibban Hamka, Rully Tri Abdul Malik-

Geothermal ITB) [037]

Identifying the Distribution of Alteration Zone Using Very Low Frequency Method in Candi Gedong Songo, Ungaran, Semarang,

Central Java (Alfianto, A.D., Almas, S.A., Ambariani, S.G., Kurniawan, W.S., Sari,

D.P., Suyanto, I - UGM) [009]

09:10 – 09:30

A Collaborative Engineering Approach To Achieve Success In Geothermal Drilling Application (Yudi Indrinanto, Manuel

Centeno Acuna, William Thomas, Michael Ari Dhanto, Agus Ziyad Kurnia, Erik Gunawan Supriatna, Bonar Marbun

Noviasta, Donny Trias Ardianto, M.R. Yoan

Mardiana-Schumberger) [116]

Literature Review Of Radar Remote Sensing Combined With Continuous GPS

Measurements For The Monitoring Of Deformations Of Geothermal Fields (Jane

Mbogo and Josephat Kebu-Kenya Electricity Generating Company)

[050]

The Cooling History Of Residual Magma As Heat Source

(I G.B. Eddy SUCIPTA and Isao TAKASHIMA-Geological Eng. ITB and

Akita Univ Japan) [112]

Characterization Of Diwak-Derekan Geothermal System Using Magnetotelluric

Data (Agung Wibawa, Udi Harmoko, Rahmat Gernowo – UNDIP) [004]

09:30 – 09:50 Geothermal Drilling Case History (ISOR)

Micro Earthquake: Principle and Case History for Geothermal Exploration and

Exploitation (Andri Dian Nugraha-ITB)

Volcanic, Magmatic and Hydrothermal Gas Discharges

(Prof. Tobias Fischer-New Mexico Univ. USA)

Magneto-telluric: Principle and Case History (Wahyu Sri Gutomo – ITB)

09:50 – 10:10

10:10 – 10:30 COFFEE BREAK

22

TIME AUDITORIUM ROOM 4 ROOM 5 ROOM 6

SESSION GEOCAP

Chairperson: Chris Hecker & Famelia

DRILLING Chairperson: Dimas Taha Maulana &

Andhika Akib

GEOLOGY-GEOCHEMISTRY Chairperson: Mahesa P. Saputra &

Rizki Trisna

EXPLORATION Chairperson: Asep Saepuloh &

Betseba Br. Sibarani

10:30 – 10:50

Quantitative Comparison of Two 3-D Resistivity Models of the Montelago

Geothermal Prospect (W.A. van Leeuwen, Suryantini, G.P.

Hersir-IF Technology, ITB, ISOR)

[096]

Geothermal Drilling: Principle and Constrained

(Bonar Tua Halomoan Marbun-ITB)

Characteristic Of Geothermal Fluid At East Manggarai, Flores, East Nusa

Tenggara (Mochamad Iqbal, Niniek Rina Herdianita, Dikdik Risdianto-ITB)

[061]

Contamination of Thermal Water to Groundwater in Kertasari Area, Bandung (Arif Susanto, Suryantini, Joshua Satriana,

Munib Ikhwatun Iman, Noriyoshi Tsuchiya-ITB, Badan Geologi, Tohoku Univ, Japan)

[133]

10:50 – 11:10

Minigeo : Small Scale Geothermal Power for Remote Off-Grid Communities

(N. Willemsen, J.H Kleinlugtenbelt, A. Willemsen-IF Technology)

[101]

Geochemical Study Of Ampalas Geothermal Area, Mamuju District, West Sulawesi Province (Fithriyani Fauziyyah, ,

Muhammad Ghassan Jazmi Shalihin, Dede Iim Setiawan, Anna Yushartanti-

ITB) [038]

The Potential and Development of Way Ratai Geothermal Prospect Area as A Solutions of

Electricity Crisis at Lampung Province (Evi Muharoroh-UNILA)

[031]

11:10 – 11:30

Hydraulic Fracturing and Coupled Modelling for Geothermal Energy

Applications (Peter Fokker-TU Delft)

Geothermal Fluid Characteristic Based on Fluid Geochemistry Analysis,

Kepahiang, Bengkulu (Novian Triandanu, Agil Gemilang R, Ichsan Alfan, Inge Sukma Y, Sapari

Hadian G-UNPAD)

[075]

Assessing The Possibility Of Enhanced Geothermal System In Western Indonesia

(Hendrawan, R. N and Draniswari, W. A-ITB)

[041]

11:30 – 11:50

Geothermal Exploration Indonesia by Means of Rock Petrology and Water

Geochemistry (Fiorenza Deon-TU Delft)

Drilling Bit Optimization In Supreme Energy Geothermal Exploration Drilling (Bambang S. Roesdyoko, Dodi A. Gauzali,

Gilang Rifki A. – Supreme Energy) [017]

Analysis on Scaling Problem in Injection Line: A Case from Muara Labuh

Geothermal Field, Indonesia (Alfiady, Robi Irsamukhti, Alfianto

Perdana Putra, Herwin Azis and Jantiur

Situmorang-Supreme Energy) [117]

Subsidence Causes, Effects, and Mitigations in Geothermal Field

(Akta Sektiawan, Ganung Adi Prasetyo, Dida Patera Adli, Ethis Yuantoro-ITB)

[008]

11:50 – 12:10

Geology Structure Identification based on Polarimetric SAR (PolSAR) Data and Field

Geological Mapping at Ciwidey Geothermal Field

(Ratna Amalia Pradipta, Asep Saepuloh,

and Suryantini-ITB) [079]

Optimal Geothermal Well Cementing A Case Of Olkaria Geothermal Field (Nahashon Karanja Nzioka-Kenya

Electricity Generating Company) [070]

Occurrence Of Sarawet Hot-spring: What Affects The Outflow?

(Draniswari, W. A and Hendrawan, R. N-

ITB) [111]

Assessment Thermal Flow Direction of Geothermal Manifestation Based on Temporal Analysis of Temperature Distribution at Pine

Forest Park, Tomohon, North Sulawesi

(Roy Wenas, Cyrke A.N Bujung-UNIMA) [131]

12:10 – 13:30 LUNCH

23

TIME AUDITORIUM ROOM 4 ROOM 5 ROOM 6

SESSION SATREPS Chairperson: M. Nur Heriawan &

Reyno

ENGINEERING Chairperson: Sutopo &

M. Mirza

EXPLORATION GEOLOGY Chairperson: Fiorenza Deon &

Yosi Amelia

EXPLORATION Chairperson: Anggie Rengganis &

Mona Natalia S.

13:30 – 13:50

Studies Design for BAGUS SATREPS Project

(Prof. Katsuaki Koike, Kyoto Univ. Japan)

A Comprehensive Well Testing Implementation During Exploration Phase in Rantau Dedap,

Indonesia (Muhammad Tamrin Humaedi, Alfiady, Alfianto

Perdana Putra, Rudy Martikno, Jantiur Situmorang-Supreme Energy) [119]

Hydrothermal Alteration; Identification and its importance in geothermal

exploration and exploitation (Pri Utami-UGM)

3D Geothermal Conceptual Modeling (Clare Baxter-LEAPFROG)

13:50 – 14:10

Numerical Model of Unsteady Two-phase Flow in Geothermal Production Well

(Keisuke Yamamura, Ryuichi Itoi, Toshiaki Tanaka, Takaichi Iwasaki-Kyushu Univ, Japan)

[054]

14:10 – 14:30 Radon Prospecting at Wayang Windu (T. Kubo, and K. Koike,

Kyoto Univ. Japan)

On the Feasibility of Geothermal Heat Production from A Hot Sedimentary Aquifer : A Case Study of the Jababeka District, West Java

(Nurita Putri Hardiani, Setya Drana Harry Putra – Geothermal ITB)

[134]

Conceptual Model Of Sorik Marapi Geothermal System Based On 3-G Data

Interpretation (Birean D. Sagala, Vicky R. Chandra,

and Dorman P. Purba-SORIK MARAPI GEOTHERMAL POWER) [019]

Geological, Isothermal, and Isobaric 3-D Model Construction in Early Stage of

Geothermal Exploration (Mahesa Pradana Saputra, Suryantini,

Danilo Catigtig, Riky Regandara, Sitti Nur Asnin, Angga Bakti Pratama – Geothermal

ITB, Emerging Power Inc., Philippiners) [107]

14:30 – 14:50

Hydrogeochemistry Study at Bandung Basin

(Andre, Irwan Iskandar, Sudarto N.-ITB)

Mathematical Modelling of Silica Scaling Deposition in Geothermal Wells

(Muhammad Nizami and Sutopo-ITB) [066]

Use Of Sub-Terrain Technology In Geothermal Exploration

(George Barber, Madjedi Hasan and Anton Wahjosudibjo-IEP and

PENConsulting) [122]

Classifying Hot Water Chemistry: Application Of Multivariate Statistics

(Prihadi Sumintadireja, Dasapta Erwin Irawan, Yuano Rezky, Prana Ugiana Gio,

Anggita Agustin-ITB, USU) [114]

14:50 – 15:10

Characterizing Geothermal Surface Manifestation Based on

Multivariate Geostatistics of Ground Measurement Data

(Ishaq, M. Nur Heriawan, Asep Saepuloh-ITB) [048]

Decline Curve Analysis in Liquid-Dominated Geothermal Reservoir for Optimizing and

Forecasting in Production (Iki Hidayat-ITB)

[044]

Influence of Hydrothermal Alteration on Petrophysical Properties of Rocks in

the Cibolang Area, Bandung (Arif Susanto-ITB)

[132]

Geology and Prospecting for Hidden Geothermal System of Manglayang

Volcano Complex of Bandung-West Java (Subandrio, AS., Sumintadireja, P., Irawan,

D., and Suryantini (ITB) [135]

15:10 – 15:30 COFFEE BREAK

24

TIME AUDITORIUM ROOM 4 ROOM 6

SESSION SATREPS – Remote Sensing Chairperson: Roy Wenas & Akhmad

Kunio Pratopo

DIRECT USE Chairperson: Jooned H. & Waldy Afuar

POWER PLANT Chairperson: Nur Santy Elizabeth & Fuad

15:30 – 15:50

The Effectiveness of Hydrothermal Alteration Mapping based on

Hyperspectral Data under Tropical Region (Reyno Rivelino D.M and Asep Saepuloh-

ITB) [081]

Experimental Study of Isothermal Plate Uniformity For Blood Warmer Development

Using Geothermal Energy (Y. Ichsan, J. Hendrarsakti-ITB) [098]

The Development of Integrated Plant Model by Utilizing Wasted Heat in Water-dominated

Geothermal Source (Cukup Mulyana, Aswad H. Saad, M. Ridwan Hamdani, Fajar Muhammad-

UNPAD) [022]

15:50 – 16:10

Identification of Surface Manifestation at Geothermal Field Using SAR Dual Orbit

Data (Dinul Akbari and Asep Saepuloh-ITB) [024]

A Preliminary Research Of Direct Contact Geothermal Steam Condensation In The

Presence Of Non Condensable Gas (Vivi A, Willy A, Ari D. Pasek, YB. Agastyo N,

Candra M. S, Abdurrachim-ITB) [118]

Economic And Thermodynamic Analysis For Preliminary Design Of Dry Steam Geothermal

Power Plant (GPP) With Multifarious Gas Removal System (GRS) in Kamojang, West Java, Indonesia (A. Damar P, Sihana, Kutut S, Fiki R. S-

UGM) [002]

16:10 – 16:30

Identification of Geothermal Fluid Paths at Ground Surface on Segment Tracing

Algorithm (STA) of the ALOS PALSAR Data (Haeruddin, Asep Saepuloh, and M. Nur

Heriawan-ITB) [039]

Geothermal Direct Use Development To Optimize Renewable Energy Utilization For

Agricultural, Aquacultural And Tourism Activities In Indonesia

(Nicolas Jalu Pangesty, Muhammad Dzulfikri Firdaus, Adidanu Saputra-UNDIP)

[074]

Energy Optimization Modeling Of Geothermal Power Plant (Case Study: Darajat Geothermal

Field Unit III) (Rizal Sinaga-DEL) [083]

16:30 – 16:50

Performance Analysis of Mineral Mapping Method to Delineate Mineralization Zones Under Tropical Region (Muhamad Hardin

Wakila, Asep Saepuloh, and M. Nur Heriawan-ITB) [062]

Feasibility Of Geothermal Energy Extraction From Non-Activated Petroleum Wells In Arun

Field (Muhammad Syarifudin, Kalvin Maurice,

Franky Octavius-ITB) [067]

16:50 – 17:10 CLOSING CEREMONY (DOOR PRIZE, BEST POSTER AND BOOTH ANNOUNCEMENT)

25

Poster Session

Wednesday-Thursday, March 30-31st 2016

No. Paper Title Paper ID

1 Usage of Zheolite-Chitosan as Impurities Filter to Reducting Corrosion Turbine on Geothermal Plant (Ainul Yaqin Abror A,Jesica Indah O.Wildan Ichsan S,Risko Pratama Y-UNIBRAW)

007

2 New Challenges: Feasibility Study of New Drilling and Production Technologies for Offshore Geothermal Resources in Indonesia (Deni Setiawan, Muhammad Syarif Ali Akbarsyah-ITB)

023

3 The Functional Shift of Old Central Sumatra Basin as Hydrocarbon Wells to Non-Volcanic Geothermal Field: Optimization Injection Wells and Production Wells as an Effort to Create National Energy Sovereignty (Djati Wicaksono Sadewo, Nicholas Bastian, Ridwan Chandra, Sekar Indah Tri Kusuma-UNDIP)

025

4 Integration of MT-CSAMT and Resistivity Log for Determining Geothermal Reservoir Model Based on Convection Heat Energy Transfer (Faid Muhlis and Risca Listyaningrum-University of Pembangunan Nasional "Veteran" Yogyakarta)

032

5 Identifying Non-Volcanic Geothermal Potential in Amohola, Southeast Sulawesi Province, By Applying Fault and Fracture Density (FFD) Method (Fajar Mulyana, Gian E. Tsani, Kiddy Nahli, M. Aulia Alwan, M. Hilman Darojat, Rezky N. Hendrawan-UNPAD)

033

6 Geothermal System of Mount Ungaran, Central Java, Indonesia: Characterization, Conceptual Model, and Potential (Ibnu Dwi Bandono Wahyudi-Patra Nusa Data)

043

7

Repeat Absolute and Relative Gravity Measurements for Geothermal Reservoir Monitoring in Ogiri Geothermal Field, Southern Kyushu, Japan (Jun Nishijima, Chika Umeda, Yasuhiro Fujimitsu, Jun-ichi Takayama, Naoto Hiraga and Satoru Higuchi-Kyushu University, Japan)

051

8 Volcanological Approaching for Evaluation of Geothermal Potential in Galunggung Mountain (Qodri Syahrur Ramadhan, Akhmad Kunio Pratopo, Juni Yesy Sianipar-Geothermal ITB)

052

9 Characteristic of Geothermal Reservoir Based on Analysis of Surface Manifestation, Fluid Geochemical and Rock Alteration; Case Study of Ungaran Volcano Geothermal Area, Central Java, Indonesia (Muhammad Afkarul Haq, Farchan Nauval, Nashir Idzharul Huda-UNDIP)

063

26

No Paper Title Paper ID

10 The Concept of Steam Field and Geothermal Power Plant (PLTP) Development Plan, Case Study at Mount Rajabasa (Nanda Hanyfa Maulida and Suharno-UNILA)

072

11

Estimation of Geothermal Speculative Resource Potential Using Geochemistry Method in East Manggarai Regency, East Nusa Tenggara Province (Teguh Rahat Prabowo, Muhammad Ghassan Jazmi Shalihin, Aton Patonah, Fithriyani Fauziyyah, Andri Eko Ari Wibowo-UNPAD, ITB, PSDG)

093

12 Electricity Generation from Hydrothermal Vents (Yuzar Aryadi, Imam Saiful Rizal, and Muhammad Nur Fadhli-ITB)

099

13 Design of Tomato Drying System by Utilizing Geothermal Brine (Afuar Waldy, Sibarani Betseba, Abdurrahman Gugun, J. Hendarsakti-Geothermal ITB)

104

14 Natural State Modelling in Hululais Geothermal Field Based on Exploration Data (Pudyo Hastuti, Sutopo and Marihot Silaban-Pertamina Geothermal Energy and ITB)

129

15

A Comparison Analysis between Russel James Equation and Hiriart Equation in Horizontal Discharge Lip Pressure for Production Test at Geothermal Well Using Statistical Method (Muhammad Nizami-ITB)

065

16 Geothermal Exploration Impact In Ground Water Level Case Study: Gedongsongo, Ungaran, Semarang, Jawa Tengah (Annisa Rizqilana, Hafidz Galant Amirul, Anindya Estiandari, Fandy Fahreza-UNDIP)

015

27

PROGRAMME

Post – Workshop

28

29

Field Trip

Friday, April 1st 2016

The Patuha geothermal system is a vapor-dominated reservoir located about 40 kilometers southwest of Bandung on western Java, Indonesia. The geothermal system consists of a cap rock, an underlying steam cap and a deep liquid-dominated reservoir. The reservoir is provided with heat by a main heat source below Kawah Putih and the Patuha volcano. The flow of fluid takes place through fault zones and in the low permeability reservoir rock. . The first Unit (55 MW) at Patuha was completed in 2014 and since 2015 it has been producing at full capacity (with an availability rate of over 98%). Purpose This one full day field trip to Patuha Geothermal Plant provides an introduction to geothermal resources and their utilization. The trip may include visits to Patuha Power Plant, Steam Field, Surface Facilities and observations to the surface features/manifestations of the Patuha thermal areas. Transportation We will provide participants with mini-buses for mobilization purposes. Participants will not drive their own vehicles to and from the destined locations. The provided buses will depart from Bandung on April 1st morning to Patuha Geothermal Plant. Instructors The Field Trip will be guided and instructed by the lectures and graduate students of the ITB along with Geo Dipa representatives.

Run Down: April 1st , 2016 05.45-06.00 Gather at ITB campus gate

06.00-08.00 Travel to PT. Geodipa (Patuha)

08.00-09.00 Safety Induction

09.00-09.15 Coffee Break

09.15-11.30 Introduction about power plant from PT. Geodipa

11.30-13.00 Break and Lunch

13.00-17.00 Trip to power plant

17.00-19.00 Travel to Bandung (ITB)

30

Field Camp

Friday-Saturday, April 1st-2nd 2016

What you will learn?

The participant will learn the full circle of applied geochemical work for geothermal survey. This includes the theory on geothermal geochemistry, the practical work on collecting samples, carry out the laboratory analyses, interpret the results and presenting the data.

What are the activities?

During 2 days program, the participant will stay one night in Geothermal Field Campus at Lembang about 5 km south of Tangkuban Perahu Volcanoe, have class acticities in the camp, visit the Tangkuban Perahu Geothermal Surface Manifestation and visit Thermochem Lab Facilities. The program cover class activities such as theory, data analysis and data presentation, and practical field to collect gas and water samples, and analyze the samples at the Thermochem Laboratory.

Who should attend

Earth scientist interested in geochemical survey such as geologist, geochemist, chemist, field sampling operator, environmental scientist, or just beginner learn about geochemical sampling and survey in particular for geothermal.

Purpose

In particular, the goal of geothermal field camp is to provide participants with basic knowledge and practical field techniques of geothermal exploration. These skills would be complemented by basic data collection, sampling and theoretical data analysis that is fundamental for any interpretation and assessment of reservoir potential.

All exercises will be completed in Domas Crater and Ratu Crater, in which these fields allow the integration of field based structural geological analysis, observation and sampling of geothermal manifestations as hot springs and sinters and also ultimately of structural geology and surface geochemistry. This program introduces basic methods used in exploration geology to study both, fault and fracture systems and fluid chemistry to give a better understanding of the selective fluid flow along certain fractures and faults. Field geology covered the systematic measurement of faults and fractures, fault plane and fracture population analysis. In addition, field hydro-geochemistry focused on sampling techniques and field measurements onsite.

Transportation & Accommodation

We will provide participants with vans for mobilization purposes. Participants will not drive their own vehicles to and from camp locations. The provided vans will depart from Bandung on April 1st evening to stay overnight at the geothermal campus located in Lembang (± 45 km from Bandung) soon after the workshop closing ceremony. The field camp participants will return to Bandung on April 2nd evening.

31

Instructors

The field camp courses are taught by Prof. Tobias Fischer from New Mexico University, USA, the lecturers and graduate students of the ITB Geothermal Magister Degree Program: Instructor to participant ratios is ~ 4:1.

Run Down:

Day – 1 ( April 1st , 2016)

06.00-06.30 Gather at ITB campus gate

06.30-07.30 Travel to Geothermal Field Campus, Lembang

08.00-10.00 Morning class lecture: Geothermal Geochemistry

10.00-11.00 Travel to Tangkuban Perahu Volcano

11.00-12.30 Observation of Ratu and Upas Crater, Friday Praying for Moeslem, Lunch

12.30-13.00 to Domas Crater

13.00-17.00 Practical : collect gas samples at Fumaroles in Domas Crater , collect water samples, alteration observation

17.00-18.00 to Geothermal Field Campus Lembang

18.00-19.00 Private time

19.00-20.00 Dinner

20.00-21.00 Night discussion and lecture

Day – 2 ( April 2nd , 2016)

07.00-08.00 Travel to Thermochem Lab (Participant bring all the lugage, we will not go back to Lembang field campus)

08.00-12.00 Practical : using Gas Chromatrography, and other facilities at Thermochem Laboratory

12.00-13.00 Lunch Break

13.00-16.00 Data Interpretation and Presentation

16.00-16.30 Closing of the field camp program

16.30-18.00 Travel to Bandung (ITB)

32

33

ABSTRACT

Technical Paper and Poster Session

34

Paper ID : 002

Economic And Thermodynamic Analysis For Preliminary Design Of Dry Steam Geothermal Power Plant (GPP) With Multifarious Gas Removal System (GRS) in Kamojang, West Java, Indonesia

Aloysius Damar Pranadi.

a, Sihana

b, Kutut Suryopratomo.

c Fiki Rahmatika Salis

d

a,b,c,d Nuclear Engineering and Engineering Physics Department, Faculty of Engineering, Universitas Gadjah Mada,

a,b,c,d 2 Grafika Road, Sleman, Yogyakarta, Indonesia

a damarpranadi@gmail.com,

b kutut@ugm.ac.id,

c dr_sihana@yahoo.com

d fikirahmatikasalis@gmail.com

ABSTRACT

According to Revision of Geothermal Resources Counting Presentation at IIGW 2015 by Mr. Amir Fauzi, Indonesia has great number of geothermal potential separated by two kind of potential, 16.13 GW for high enthalpy and 7.88 GW for low enthalpy speculative resources. In the end of 2013, Ministry of Energy and Mineral Resources stated that Geothermal Power Plant (GPP) have been existed about 1.34 GW and wanted to seriously develop geothermal potential up to 6.64 GW by 2025. Cost is one of famous obstacle in Indonesia’s GPP Development. To reduce grand total cost of GPP, this paper will present the relation between thermodynamic and economic analysis in purpose to find the most economical gas removal system in GPP. By gleaning data at Kamojang Steam Field on behalf of PT Pertamina Geothermal Energy, this study will thermodynamically analyze and calculate a GPP preliminary design with software, named as Cycle Tempo 5.0. In additional, writers create motive steam calculator (based on C++ language) to enhance thermodynamic analysis for gas removal system (GRS). After thermodynamic analysis has been done, economic study will be undertaken by Net Present Value Analysis to compare the utilization cost of three different GRS and find which kind of GRS is more economical for nearly 30 years operation. For the result, Dual LRVP has higher performance than the others, spend less based on NPV utilization cost and is more economical for nearly 30 years operation. In conclusion, GPP with Dual LRVP is proper to be developed in the future Geothermal Power Plant or to replace the existing GRS in some existing GPP in Indonesia. Keywords: Geothermal Power Plant; Thermodynamic Analysis; Economic Analysis; Gas Removal System

Paper ID : 004

Characterization of Diwak-Derekan Geothermal System Using Magnetotelluric Data

A Wibawa1, U Harmoko

1, L Handayani

2

1Physics Department, Diponegoro University

Jl. Prof. Soedharto, Tembalang, Semarang, Indonesia 50275 2LIPI Center for Geotechnology Research

Jl. Sangkuriang, Kompleks LIPI, Bandung, Indonesia 40135 agungwibawa@outlook.com

ABSTRACT

An investigation of the Diwak-Derekan geothermal field using magnetotelluric survey has been conducted. Initial geological survey provided clue that the most likely area to find a heat source is on the Southeastern region of an acreage covering 433000-445000 longitude and 9200000-9210000 latitude as it is dominated by the presence of breccia. But inversion result of the gathered data indicate that any sign of heat source is not detected in that suspected region as lower resistivity layers extend to 5,000 m deep. However, a promising signature of a heat source is detected on the upper part of that region, an area filled with lava. This finding is certainly interesting, and hence it is deemed that the Diwak-Derekan geothermal field is located on a bed of rocks resulted from an uplifting seafloor that make up most of the Java island. This should give advantage as thicker layer of rocks may help keep high temperature at the reservoir that makes it a promising geothermal prospect. Keywords: magnetotelluric, resistivity layer, high temperature reservoir.

35

Paper ID : 007

Usage of Zheolite-Chitosan as Impurities Filter to Reducting Corrosion Turbine on Geothermal Plant

Ainul Yaqin Abror. H, Wildan Ichsan Sabila, Risko Pratama Yuda, Jesica Indah Oktaviana Geophysics Sub-Department, Physics Department, Mathematics and Natural Sciences Faculty, Brawijaya University

Jalan Veteran, Malang, 65145, Jawa Timur, Indonesia risko.yuda@gmail.com; wildan.geophysics@gmail.com

ABSTRACT

Geothermal energy is one of the renewable and eco-friendly energy. Geothermal energy in general can be identified by its surface manifestation which are hot springs or geyser. Geothermal energy can be used as a power plant by taking hot steam on reservoir using exploratory wells. Yet, on exploration process, hot steam still has impurity substances which can induce turbine corrosion on geothermal plant. In order to resolve this problem, separator is in use to separating steam and water along its impurity. But this solution is less effective because there are still impurity substances passing through after separating process. Zeolites are microporous aluminosilicate mineral and have its uses as adsorbents. Zeolite’s usage as a adsorbent is used to optimize impurity substances adsorbs on geothermal plant. Zeolite chitosan as one of modified natural zeolite is used in this system, in which zeolite in the form of powder is formed to be a clumps using chitosan as an adhesive. This type of zeolite has higher adsorption capacity than activated zeolite. Zeolite chitosan is formed into a hollow cylindrical filter and is installed in circular on steam wash system area before the turbine, so that corrosion of the turbine can be reduced. Keywords: Corrosion, Pipe, Geothermal Plant, Zeolite, Chitosan

Paper ID : 008

Subsidence Causes, Effects, and Mitigations in Geothermal Field

Akta Sektiawan, Ganung Adi Prasetyo, Dida Patera Adli, Ethis Yuantoro

Institut Teknologi Bandung Jalan Ganesa no. 10 Bandung

akta.sektiawan@students.itb.ac.id

ABSTRACT Subsidence is the motion of the ground surface as it moves down relatively. It can occur in a wide range of area. It is an impact of production of large mass and volume of fluid from the reservoir. It doesn’t happen especially in geothermal fields only, but also in oil and gas industry. Large fluid volume production leads to the decrease of pore pressure inside reservoir. This decline disturbs the pressure stability and overburden pressure compress the pores. It results the drop in ground surface. The decrease in ground surface level induces a devastating effect in the construction of some facilities, such as building, pipeline, canal, and river. It may interrupt the balance in the ecosystems nearby. Good management and several survey methods ( such as levelling and gravity ) will reduce the risk of subsidence and the other effects related to it. This discussion output can be used as a guide for minimizing subsidence impact in the geothermal field in general.

36

Paper ID : 009

Identifying the Distribution of Alteration Zone Using Very Low Frequency Method in Candi Gedong Songo, Ungaran,

Semarang, Central Java

Alfianto, A.D. 1,2,*

, Sari, D.P. 1

, Almas, S.A. 1

, Kurniawan, W.S. 1

, Ambariani, S.G. 1

, Suyanto, I 1

1 Geophysics Sub-Department, Faculty of Mathematics and Sciences, Universitas Gadjah Mada

2 Geology and Geophysics Engineer PT. Pertamina EP Asset 3, Third Party Contract PT. Pranalika Energi Nusa

agungdwi.alfianto@yahoo.co.id

ABSTRACT The alteration zone could be a key link and a proof to know where the ancient heat source was previously located. An electromagnetic survey to identify and to map the lateral and vertical distribution of alteration zone had been done at geothermal area Candi Gedong Songo, Ungaran, Central Java, from 9th – 19th of June 2014, using Very Low Frequency (VLF) method. The survey consisted of 6 profiles, with NW – SE direction, which were located nearby the fumaroles spots and then went down to the observed alteration zone. Each profile was 600 m long and the distance between each profile was 20 m. The space between each measurement point of a profile was 20 m. In this study, tilt and ellipticity data with frequency of 19.8 kHz (Japan) and 24 kHz (Panama) were used. First, the data was processed to get the cross features anomaly between tilt and ellipticity data on the chart. Then, the derivative fraser and the relative current density pseudosection were also made to support the cross features anomaly. The interpretation of this data was done qualitatively using fraser and relative current density pseudosection. The result shows that the alteration zone gives high response of conductivity compared to its surrounding area. This is supported by the anomaly cross features between tilt and ellipticity data on the chart, also by high value of fraser and relative current density. Thus, from the result, the alteration zone are located in meter 150 – 250 in V1 and V2 profiles, also in meter 180 – 250 in V5 and V6 profiles. This result indicates that the ancient heat source was previously located nearby the fumaroles area and it is physically shown by the presence of sulphuric clay mineral content at the alteration surface area. Keywords: alteration zone, conductive zone, geothermal, VLF Method

Paper ID : 015

Geothermal Exploration Impact in Ground Water Level Case Study: Gedongsongo, Ungaran, Semarang, Jawa Tengah

A Rizqilana, H G Amirul ,F Fahreza and A Estiandari Geological Engineering, Engineering Faculty, Universitas Diponegoro

Semarang , Central Java fandyfahrezag13@gmail.com

ABSTRACT

Geoscientific investigation and research in Gunung Ungaran geothermal area had been carried out and showed that temperature of the reservoir is about 230̊C and the power is 15 MWe/km2. If geothermal fluid to electricity conversion factor is 15%, so that the electricity power is 2,25 MWe/km2 (Wahyudi, 2005). If the area of the prospect is about 5 km2, so that the realistic power can be used is 11,25 MWe. Gunung Ungaran geothermal area had been proposed to be developed as geothermal power plants and from several cases like in Wairakei, geothermal exploration give impact on ground water level that showed grown water level drawdown until 14 meters in 50 years because of geothermal exploration. So that, in this case there are ground water level impact comparation between Wairakei geothermal and Gunung Ungaran Geothermal. Gunung Ungaran known as supplier of drinking water production for several companies in Gunung Ungaran. In this paper, there are some information about Gunung Ungaran from geoscience investigation especially in groundwater research and geothermal aspect that showed Gunung Ungaran had aquifers 30 until 90 meters underneath surface and water discharge quantities 60 liters/second. Groundwater itself impact with geothermal because existence of groundwater would give imperishable factor for geothermal. In contrast, exploitation of geothermal could decrease ground water level. Decreasing ground water level would give impact on companies that use Gunung Ungaran groundwater for drinking water. So that, there are several ways to prevent decreasing ground water level with infiltration wells that made in some place that give effective impact for groundwater. Development in geothermal power plant should pay attention in groundwater and preventive action have to be considere

37

Paper ID : 017

Drilling Bit Optimization In Supreme Energy Geothermal Exploration Drilling

Bambang S. Roesdyoko, Dodi A. Gauzali, Gilang Rifki A. PT. Supreme Energy Muara Laboh

Menara Sentraya 23rd

Fl, Jl. Iskandarsyah Raya No. 1A Jakarta - 12160 bambang-roesdyoko@supreme-energy.com; dodi-gauzali@supreme-energy.com; gilang-arif@supreme-energy.com

ABSTRACT

Muara Laboh prospect was interpreted, based on the pre-feasibility study, as high temperature outflow with distributed permeability system. The prospect is located along Great Sumatran Fault (GSF), with surface manifestation indicated the existence of a High Temperature system (>220°C) from geochemistry sampling. Exploration drilling program then carried out by drilled total of six (6) exploratory wells to prove and delineate the Muara Laboh geothermal prospect on 2012/2013. The drilling key performance levels are carefully identified and measured to ensure the drilling performance improve consistently and meet the target of exploration program. One of drilling key performance is the drilling bit optimization. This paper describes drilling bit optimization process - starting from bit data gathering and assortment, bit selection for early wells in the program, and bit selection refinement - and also shows the bit run results and analysis. There were six (6) exploration wells drilled in Muara Laboh and six (6) exploration wells drilled in Rantau Dedap.

Paper ID : 019

Conceptual Model Of Sorik Marapi Geothermal System Based On 3-G Data Interpretation

Birean D. Sagala, Vicky R. Chandra, Dorman P. Purba

Geoscience Department, Sorik Marapi Geothermal Power Recapital Building 5

th Floor Jalan Adityawarman Kav 55 Jakarta Selatan Indonesia

bdsagala54@gmail.com, vickyraychandra@gmail.com, dorman.drilling@gmail.com birean.sagala@otp-sorikmarapi.co.id, vicky.chandra@otp-sorikmarapi.co.id, dorman.purba@otp-sorikmarapi.co.id

ABSTRACT

This paper discusses conceptual geothermal model of the Sorik Marapi area that is based on 3-G (Geology, Geochemistry and Geophysics) survey data includes: geometry, fluid characteristic, temperature and geological-structural setting. This model is aimed to predict potential power resource and for drilling exploration planning. The survey activity includes field geological-structural mapping and collects rock, fluids samples, MT (magnetotelluric) and -Gravity survey or commonly called 3-G survey. Subsequently the collected data processes through a sequences of laboratory test activities and results are discussed and interpreted and integration all them for a final preliminary geothermal model. Geologically, the Sorik Marapi area is formed and covered by sequences of rocks from young to old including: young volcanic rock of the Sorik Marapi activity and old volcanic rocks unit (none related to Sorik Marapi) and sedimentary rocks and structurally the volcanic activities strongly related with the Active Sumatran Fault Zone (SFZ). Geophysical survey (MT and gravity) has indicated that there are four prospective areas named: Sibanggor Tonga, Roburan Dolok, South Sampuraga and Sampuraga. Geochemistry results indicated those prospect areas are mature geothermal system and contrast with gas-fluids characteristic from active Sorik Marapi volcano. Estimation of deep reservoir based on gas geothermometry in Sibanggor Tonga and Roburan Dolok range from 250

oC to 325

oC and for Sampuraga prospects

range from 180oC to 220

oC.

Data interpretation and integration of Sorik Marapi field showed mature geothermal system are found in the low elevation of Sibanggor Tonga, Roburan Dolok and Sampuraga and in contrast with the Sorik Marapi volcano system. A deep exploration drilling program is needed to explore and test this model. Keywords: geothermal system, 3-G surveys, conceptual model, data interpretation, Sorik Marapi

38

Paper ID : 022

The Development of Integrated Plant Model by Utilizing Wasted Heat in Water-dominated Geothermal Source

Cukup Mulyana*, Aswad H. Saad, M. Ridwan Hamdani, Fajar Muhammad

Department of Physics, Universitas Padjadjaran Jl. Raya Bandung-Sumedang Km.21

c.mulyana55@yahoo.com

ABSTRACT In the geothermal power plant the brine from the single flash is commonly injected to the ground. The high temperature and enthalpy of brine has a great potential to be used as energy source to generate electric power. Utilizing the brine and using HYSIS software the integrated model of geothermal power plant from water dominated source has been developed. The 265

oC compressed liquid flows from the well to the well head. In the well head two phase liquid with the composition

of 20% steam and 80% are separated. The steam drives 10 bar turbine and it generates 74 MW with 77% efficiency. The double flash is operated then the steam drives 7 bar turbine and generates 28 MW with 77% efficiency. The brine from the double flash is used as a heat source it boils and evaporates i-pentene which is used as a working fluid of binary cycle power plant. Two different binary cycle power plants are developed, one with recuperator, and the other without recuperator. The power of binary cycle with recuperator is 8.3 MW, with the mass flow 412 ton/h and efficiency of 78%. The power of binary cycle without recuperator is 18 MW, with mass flow 1230 ton/h and efficiency of 79%. This integrated model can improve power to a level of 24.5% without drilling the new well. The use of recuperator will decrease the amount of working fluid and will increase the brine temperature out from pre-heater. This high temperature will protect the calcite solved in brine to be formed, so it is economically valuable because it reduces the need of organic fluid. Key words: Integrated cycle, Dominated water, flashing, binary cycle, recuperator.

Paper ID : 023

New Challenges: Feasibility Study of New Drilling and Production Technologies for Offshore Geothermal Resources in

Indonesia

Deni Setiawan 1, Muhammad Syarif Ali Akbarsyah

2

1 Institut Teknologi Bandung, Jalan Ganesha 10, Bandung, West Java, 40132, Indonesia

2 Univeristas Padjadjaran, Jalan Raya Bandung Sumedang Km. 21, Jatinangor, Jawa Barat 45363

deni.setiawan.tm@gmail.com

ABSTRACT Geothermal, as a new potential renewable source of energy, has been developing in all over the world rapidly. One of the ways in developing geothermal energy is by increasing the number of exploration and exploitation drilling wells (Marbun et al. 2014). The area of geothermal energy is not only covers on land, but also extends offshore. The objective of drilling a geothermal well is to make the hole as quickly as possible subject to technology, operational, quality and safety constraints associated with the process. The methodology used in this study are integrated offshore drilling applied for geothermal well and geological consideration. Feasibility studies are subdivided into a number of specific tasks to provide a systematic, sequential approach to developing an optimum design. Properties analyzed in this study was included drilling design. In the implementation of governance for development, Sangihe Islands Regency is used as case study which divided into five clusters. However, to get better understanding, the case simulated and equation derived in this study will represents circulating condition in the drilling and/or production operation. In the conclusion, the result of this study is offshore geothermal drilling can be properly applied for future exploration and potential of offshore geothermal can be exploited when economic limit meet requirement and feasible.

39

Paper ID : 024

Identification of Surface Manifestation at Geothermal Field Using SAR Dual Orbit Data

Dinul Akbari1, Asep Saepuloh

2

1Faculty of Mining and Petroleum Engineering, Bandung Institute of Technology (ITB)

2Faculty of Earth Sciences and Technology, Bandung Institute of Technology (ITB)

Jl. Ganesha No.10, Bandung, West Java, Indonesia. 40132. dinul_akbari@yahoo.com

ABSTRACT

Wayang –Windu in West Java, Indonesia is a geothermal field located under tropical area and identified by high precipitation, dense vegetation, and existence of geothermal surface manifestation. The high precipitation caused convection clouds in the atmosphere. The convection clouds and dense vegetations on the equator inhibit identification of surface manifestation using remote sensing techniques. This inhibiting factors could be reduced by microwave sensor on satellites with Synthetic Aperture Radar (SAR) system. The dual orbit were used to observe the differentiation of object on the surface event although high precipitation and dense vegetation cover the field. This study is aimed to identify surface manifestation based on Geomorphologic and Structural Features using SAR dual orbits. The Linear Features Density SAR (lifedSAR) method was applied to detect and quantify structural features at surface. The LifedSAR method utilized by SAR dual orbit could identify the LFD related to surface manifestation zones. The surface manifestations could be detected at Wayang and Cibolang craters correctly in the middle part of the LFD map. The surface manifestations on Wayang Windu were located at the green portion with density 45 %. The field observations and soil measurements were used to confirm the correctness of the lifedSAR result, especially at surface manifestations and crater rims. Keywords: SAR dual orbit, LifedSAR, surface manifestations, Wayang-Windu geothermal field.

Paper ID : 025

The Functional Shift Of Old Central Sumatra Basin as Hydrocarbon Wells To Non Volcanic Geothermal Field:

Optimization Injection Wells and Production Wells As An Effort To Create National Energy Sovereignty

Djati Wicaksono Sadewo1, Nicholas Bastian1, Ridwan Chandra1, Sekar Indah Tri Kusuma1 1 Prodi S1 Teknik Geologi Universitas Diponegoro, Fak. Teknik Universitas Diponegoro

Jala. Prof.Soedarto, S.H Tembalang-Semarang Ridwanchandra_geo@yahoo.com

ABSTRACT

Indonesia has 40% of world's geothermal resources potentially 28.617 MW (Indonesia Energy Outlook 2014). Beside volcanic geothermal, there are another untapped geothermal such as hot dry rock and hot sedimentary aquifer (Dudi Hermawan et al,2011). One of non-volcanic geothermal field could potentially be a source is Central Sumatra basin. Central Sumatra basin has basement in form of hot dry rock (granite), with thermal gradient of 67.5°C/Km (Carvalho et al, 1978) and 3 km depth (Ikhwan Dwi, 2001). Central Sumatra basin which is currently operated as oil and gas field, has untapped non-volcanic geothermal potential which could be exploited by optimizing the injection wells and production

wells with enhanced geothermal systems technology. Optimization in injection wells is necessary due to high costs in

fracturing and could be addressed with PAA-CO2 fracturing fluid. The high number of heat loss in production wells also could be overcomed by refractories mineral which could maintain the temperature of steam in production pipe. This optimization method is expected to limit production costs and increase production of geothermal steam. Additionally, if oil and gas reserves in Central Sumatra Basin is not longer economical, this hot dry rock utilization will be a solution to maintain economic value of the basin.

40

Paper ID : 031

The Potential and Development of Way Ratai Geothermal Prospect Area as A Solutions of Electricity Crisis at Lampung Province

Evi Muharoroh

Geophysical Engineering Department, Faculty of Engineering, University of Lampung Jln. Prof. Dr. Soemantri Brojonegoro No. 1 Bandar Lampung

evimuharoroh96@gmail.com

ABSTRACT Indonesia lies at the confluence of three active tectonic plates, the Eurasian, Indo-Australian and Pacific, which part of the ring of fire. This plate interaction results in a series of active volcanoes from the western Sumatera to the southern Java. With this geologic setting, Indonesia has a significant estimated geothermal potential of about 27.5 GWe, 40% of the geothermal potential in the world. Lampung province located at the southern tip of Sumatera, has an estimated geothermal potential of approximately 2710 MWe. One geothermal prospect in the province, Way Ratai geothermal prospect area alone has a potential of 300 MWe. Geothermal energy is stored in the subsurface rocks and the fluid that contained therein. Geothermal energy in Indonesia is generally located near of a volcano and usually used for agricultural drying, home heating, and electrical generation. Geologically, Way Ratai area is located at the confluence zone between the Eurasian Plate and the Indo-Australian Plate which forms the Menanga Fault, one of the Sumateran Fault segments. It has been postulated that the Menanga Fault has given rise to the Ratai primordial Volcano. Based on geological surveys, there are several areas of geothermal manifestations around the Ratai Volcano which include steaming ground, rock alteration, and five hot springs with temperature 85-98°C. geothermometry of the fluids from these springs indicate a reservoir temperature of 200-240°C. These data suggest that Way Ratai geothermal prospect area has a good potential for geothermal electrical generation. Geothermal development of this prospect should contribute to solving the energy crisis in Lampung Province. Keywords : geothermal, Way Ratai, energy crisis

Paper ID : 032

Integration of MT-CSAMT and Resistivity Log for Determining Geothermal Reservoir Model Based on Convection Heat

Energy Transfer

Faid Muhlis [1], Risca Listyaningrum [1] Geophysical Engineering Department, University of Pembangunan Nasional “Veteran” Yogyakarta

SWK Street 104 Condongcatur Yogyakarta faid.muhlis3@gmail.com, riscalisty@gmail.com

ABSTRACT

When the fluid is heated, the density became lesser than the fluid nearby. So it rises up through the cooler, dense water. At the top, the water cools and its density increases then causes it to sink back down to the bottom. This movement occurs until heats all of the fluid. The heat energy transfer within the fluid is called by convection. In the reality this case also happening in geothermal system due to fluid (water) in the reservoir. So by using Magnetotellurics - Controlled Source Audio Frequency Magnetotellurics and resistivity log, can be observed heat changes in geothermal areas based on the value of resistivity. So it can be made a model of the geothermal system by integrating these methods. In this case the model is reservoir will show easier response to observed than the response of the other geothermal system models. The resistivity response will indicate a relatively flat response when appropriate in the region of the reservoir because convection heat energy transfer occurs evenly. Keywords: MT, CSAMT, Resistivity Log, Reservoir, Convection

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Paper ID : 033 Identifying Non-Volcanic Geothermal Potential in Amohola, Southeast Sulawesi Province, By Applying Fault and Fracture

Density (FFD) Method

FajarMulyana, Gian E. Tsani, Kiddy Nahli, M. Aulia Alwan, M. Hilman Darojat and Rezky N. Hendrawan Faculty of Geological Engineering, Padjadjaran University, Bandung, West Java, Indonesia

Jl. Raya Jatinangor, Km. 21. Phone: (+62-22 7796545) gianetsani@yahoo.com

ABSTRACT

Indonesia has numerous volcanic areas that lead to a significant geothermal potential. The geothermal potential could be produced by volcanic and non-volcanic processes. To date, geothermal possibilities by volcanic process are the most commonly known and explored in several areas in Indonesia, whereas, geothermal potential by non-volcanic process is rarer. Therefore, Indonesia is likely has a promising non-volcanic geothermal also. Non-volcanic geothermal systems could be identified by using Fault and Fracture Density (FFD) method, lineaments analysis from SRTM and topography data, as well as using earlier research models by previous researchers. By using those methods, the existing of fractures and possibility level of area that being recharge and discharge zones for geothermal might be predicted. Thus, the result could be the next target of exploration. This paper describes the application of those methods for the Amohola region and surrounding areas in Southeast Sulawesi Province. In general, the study area has complex geological characteristics. Consequently, the methods could be applied to identifying the presence of non-volcanic geothermal system in this study area. Keywords: Fault and Fracture Density (FFD), Lineament, Non-volcanic geothermal system, Amohola, Southeast Sulawesi.

Paper ID : 037

Volcanolostratigraphic Study in Constructing Volcano Chronology and its Implication for Geothermal Resource

Estimation; Case Study Mount Sawal, West Java

Fikri Adam Dermawan, Hibban Hamka, Rully Tri Abdul Malik Magister Program of Geothermal Engineering, Faculty of Mining and Petroleum Engineering, Bandung Institute of

Technology (ITB), Jl. Ganesha No. 10, Bandung, Indonesia 40132 fikri.adam.derma@gmail.com

ABSTRACT

One of the researches that should be done before carrying out a preliminary survey on the geothermal exploration with a volcanic system or volcanic-hydrothermal is by studying the volcanic stratigraphy. Determining the center of the volcanic eruption and its distribution based on the volcanostratigraphic study will be very helpful in a direct mapping that will be implemented, given that the type and characteristics of volcanic rocks are nearly the same between one source of the eruption and the other. On this case, volcanostratigraphic study had been done on Mount Sawal, where a topographic map with a scale of 1: 100,000 is used to determine the center of eruption of each crowns, while another map with a scale of 1: 50,000 is used to identify the distribution of the monogenetic (Hummock) eruption products and crowns border in detail. It is found approximately three crowns, which are Langlayang, Sawal big crown, Pamokolan, and the Cikucang Hummock that is located on the southern edge of the Langlayang crater. These Hummock and Crowns collection will be grouped into Tasik Bregade. Based on the volcanostratigraphic analysis, DEM, and geology, the chronology of how Tasik Bregade is formed is originally from the Langlayang, Sawal big Crowns, and Pamokolan. Tasik Bregade is classified into sub-mature potential geothermal system, from the analysis results, the potential magnitude of the energy contained in the magma is at 7.4 to 12, 4 MW for 30 years, but further research needs to be done because of the detailed geological and other support data that are still lacking. Keywords: volcanic stratigraphy, topographic map, chronology, geothermal system.

42

Paper ID : 038

Geochemical Study Of Ampalas Geothermal Area, Mamuju District, West Sulawesi Province

Fithriyani FAUZIYYAH1, Teguh Rahat PRABOWO

2, Muhammad Ghassan Jazmi SHALIHIN

2, Dede Iim SETIAWAN

3, Anna

YUSHANTARTI3

1 Engineering Hydrogeology, Faculty of Earth Science and Technology, ITB, Indonesia

2 Engineering Geology, Faculty of Geology, Universitas Padjadjaran, Indonesia

3 Pusat Sumber Daya Geologi, Ministry of Energy and Mineral Resource, Indonesia

fauziyyahfithriyani@gmail.com

ABSTRACT Ampallas is one of the areas with geothermal potential which located in Mamuju district, near from the capital city of West Sulawesi. This research was carried out to understand the characteristic of this geothermal field based on chemistry of the surface manifestation, including fluid characteristic and soil anomaly. Geothermal research in Ampallas area focused on 4 hot springs; Ampallas, Batupane, Karema, and Gantungan. With average temperature around 34 – 67

0C. Ampallas hot spring water type is chloride – bicarbonate, which means it came

from the reservoir while the others are bicarbonate. Ampallas fluid plotted in partial equilibrium zone and the others plotted in immature water zone. It means the Ampallas hot springs mixed with meteoric water right after reached the equilibrium state. It is also concluded that Ampallas hot springs came from the same reservoir with Batupane, but not Gantungan and Karema hot springs. The speculative resource potential of Ampallas geothermal system is estimated around 30 MWe. But if detailed geophysical method was applied the result could be more accurate.

Paper ID : 039

Identification of Geothermal Fluid Paths at Ground Surface on Segment Tracing Algorithm (STA) of the ALOS PALSAR

Data

HAERUDDIN a

, Asep SAEPULOH b

, Mohamad Nur HERIAWAN a

a Faculty of Mining and Petroleum Engineering, ITB

b Faculty of Earth Sciences and Technology, ITB

Jl. Ganesha 10 Bandung 40132, Indonesia haedin90@gmail.com

ABSTRACT

Indonesia has potency 40% of whole geothermal energy potential in the world. An area with the potential geothermal energy in Indonesia is Wayang Windu located at West Java Province. Thus, the comprehensive understanding about the geothermal system in this area is indispensable for continuing the development. A geothermal system generally associated with joints or fractures and served as the paths for the geothermal fluid migrating to the surface. The fluid paths are identified by the existence of surface manifestations such as fumaroles, solfatara and the presence of alteration minerals. Therefore the analyses of geological structures are indispensable for identifying the geothermal potential. Fractures or joints in the form of geological structures are associated with the linear features in the satellite images. A method to determine the linear features is Segment Tracing Algorithm (STA). In this study, we used satellite image data of ALOS PALSAR in Ascending and Descending orbit modes. The linear features obtained by satellite images could be validated to the results of field observations. Thus the final interpretation is expected corresponding to the actual conditions in the field. Based on the result of study, general direction of extracted lineaments were known in Northwest-Southeast, where this direction is consistent with the general direction of faults system in field. Thus extracted lineament by using Segment Tracing Algorithm (STA) for ALOS PALSAR data was very helpful in observing the lineament phenomena which was related to the identified geothermal fluid path in study area. Keywords: Segment Tracing Algorithm (STA), ALOS PALSAR, geothermal, extracted lineaments, Wayang Windu.

43

Paper ID : 041

Assessing The Possibility Of Enhanced Geothermal System In Western Indonesia

Rezki Naufan Hendrawan1,

Windi Anarta Draniswari1

1Geological Engineering, Master Program, Bandung Institute of Technology

1rezkinaufan@gmail.com

ABSTRACT

Enhanced Geothermal System (EGS) is one of geothermal system where abnormally hot masses of low permeability rocks are found at depth. Most of EGS are related to thick and deep sedimentary basin with plutons. EGS focused on drilling at hot crystalline rock and create fractured reservoirs. Indonesia has a complex tectonic setting. There were more than 86 basins in Indonesia. Most of sedimentary basins in Indonesia were tectonically stressed. Moreover, the tectonic setting which is generally a part of the Active Continental Margin also allows the formation of plutons that can be act as hot dry rock. Several hot springs or other geothermal manifestation were found in several areas within the basin and its surrounding area. This study compares structural controls and models in different tectonic setting of main basin in Western Indonesia to get the most suitable potential reservoir for EGS. The characteristic of the South Sumatra Basin, North Sumatra Basin, Tarakan Basin, West Java Basin and East Java Basin were evaluated and compared based on its geology and geophysics characteristic. As the result, South Sumatra Basin Basin is the first rank for EGS suitability in Western Indonesia. Keywords : EGS, potential, Western Indonesia

Paper ID : 042

Numerical Simulation for Natural State of Two-Phase Liquid Dominated Geothermal Reservoir with Steam Cap Above

Brine Reservoir

Heru Berian Pratama, Nenny Miryani Saptadji Geothermal Master Degree Program, Institut Teknologi Bandung.

Jalan Ganesha No.10, Bandung, Indonesia hb.pratama@gmail.com

ABSTRACT

Hydrothermal reservoir which liquid-dominated hydrothermal reservoir is a type of geothermal reservoir that most widely used for power plant. The exploitation of mass and heat from the geothermal fluid will decrease the pressure in the reservoir over time. Therefore the pressure drop in the reservoir will have an impact on the formation of boiling zones or boiling will increase. The impacts are an increase in the fraction of steam, dryness, in the reservoir and with good vertical permeability will form a steam cap underlying the brine reservoir. The two-phase liquid dominated reservoir is sensitive to the porosity and difficult to assign average properties of the entire reservoir when there is boiling zone in some area of the reservoir. These paper showed successful development of two-phase liquid dominated geothermal reservoir and discussed the formation of steam cap above brine reservoir through numerical simulation for state natural conditions. The natural state modeling in steam cap shows a match with the conceptual model of the vapor-dominated developed by White (1971) and enhanced by D’Amore and Truesdell (1979). These paper also proofed the presence of transition zone, boiling zone, between steam cap and brine reservoir. Keywords: Numerical Simulation, Two-phase Liquid-Dominated Reservoir, Steam Cap.

44

Paper ID : 043

Geothermal System of Mount Ungaran, Central Java, Indonesia: Characterization, Conceptual Model, and Potential

Ibnu Dwi Bandono Wahyudi

PT. Patra Nusa Data Taman Tekno BSD Sector XI, Blok G2/1, Serpong, South Tangerang

ibnudwibandono@yahoo.com

ABSTRACT Mount ungaran is one of geothermal potential in Central Java and contributes ± 100 MWe. The purposes of this paper are to identify geochemical characterization, calculate the reservoir temperature and understand the geothermal system of Ungaran. Manifestations especially hot spring are namely Gonoharjo, Medini, Kaliulo, Diwak, Derekan, Kendalisodo, and Gedongsongo. One sample from Gedongsongo and one sample from Kaliulo have high concentration of chloride (Cl). Two samples from Gedongsongo have high concentration of sulfate (SO4). Therefore, samples from Kaliulo, Diwak, Derekan, Gonoharjo, Medini, Kendalisodo have high concentration of bicarbonate (HCO3). Detail concentration is shown in table 1. Regionally, the concentrations of Cl-SO4-HCO3 in Mount Ungaran are divided into three zones, deep Cl waters, dilute Cl – HCO3 waters and steam heated waters. Whereas, the concentration of Na-K-Mg in Mount Ungaran is belong to immature waters zone and partial equilibrium zone. The reservoir temperature in Gedongsongo area is ranging up from 210.25oC to 328.68oC by Na-K-Ca, 177.77oC to 274.26oC by Si (silica), 334.92oC to 553.20oC by Na-K, 4.85oC to 23.66oC by K-Mg & Li/Mg, 25.34oC to 151.92oC by Na/Li, and 177.77oC to 231.338oC by gas geothermometer. Based on the calculation, geothermal potential in Ungaran is ranging up from 34.4 MWe to 103.1 MWe with median 68.7 MWe. Keywords: Ungaran, Manifestations, Thermal fluid, Reservoir Temperature, Conceptual Model

Paper ID : 044

Decline Curve Analysis in Liquid-Dominated Geothermal Reservoir for Optimizing and Forecasting in Production

Iki Hidayat

Institut Teknologi Bandung Jl. Ganeca No.10, Jawa Barat 40132

ikihidayah@gmail.com

ABSTRACT Electrical power project in geothermal field has long time range about 30 years. The power electricity must be maintained at certain value along the time range. But, geothermal field has natural characteristic for declining in production to time. Determining decline curve model of steam production is important thing for forecasting production decline in the future. This study was developed using decline curve by production data along 3 years liquid-dominated geothermal reservoir in Ulubelu field. Decline curve in geothermal field based on decline curve in petroleum industry. The decline curve was correlated by reservoir management in geothermal. The purposes of this study to get best match model decline curve and forecasting production in the future. Based on decline curve analysis by production data in Ulubelu field, the result model decline curve is exponential model. From the model, we can get the value of decline rate in the field is 9.4 %/year. Then, the formula of forecasting steam

flow was equal 𝒒 = 𝒒𝒊 𝒆−𝟎.𝟎𝟎𝟕𝟖𝟗𝟗𝒕. By using separated system cycle in Ulubelu field, the minimal steam flowrate towards

turbine was 502018.4 ton/month. Based on formula of forecasting production and minimal steam flowrate, we can get the time make up wells to maintain steam supply for stability in generator power capacity. Keywords : decline production, curve, liquid- dominated

45

Paper ID : 048

Characterizing Geothermal Surface Manifestation Based on Multivariate Geostatistics of Ground Measurement Data

Ishaq

1, Mohamad Nur Heriawan

1, Asep Saepuloh

2

1Faculty of Mining and Petroleum Engineering, Bandung Institute of Technology (ITB), Jl. Ganesha No. 10, Bandung, West

Java, Indonesia 40132. 2Faculty of Earth Sciences and Technology, Bandung Institute of Technology (ITB), Jl. Ganesha No. 10, Bandung, West Java,

Indonesia 40132 ishaqitb14@yahoo.co.id

ABSTRACT

Mt. Wayang Windu is one of geothermal field located in West Java, Indonesia. The characterization of steam spots at surface manifestation zones based on the soil physical measurements of the area is presented in this study. The multivariate geostatistical methods incorporating the soil physical parameter data were used to characterize the zonation of geothermal surface manifestations. The purpose of this study is to evaluate the performance of spatial methods of multivariate geostatistics using Cokriging to characterize the physical properties of geothermal surface manifestations at Mt. Wayang Windu. The Cokriging method was selected because this method is favorable when the secondary variables has more number than the primary variables. There are four soil physical parameters were used as the basis of Cokriging method, i.e. Electrical Conductivity, Susceptibility, pH, and Temperature. The parameters were measured directly at and around geothermal surface manifestations including hot springs, fumaroles, and craters. Each location of surface manifestations was measured as 30 points with 30 m grids. The measurement results were analyzed by descriptive statistics to know at the nature of data. The relationship among variables was analyzed using scatterplot to obtain the linear correlation among variables. The higher correlation coefficient among variables, the estimation results is expected to have better Linear Model Coregionalization (LMC). LCM was use to analyze the spatial correlation of each variable based on their variogram and cross-variogram. To evaluate the performance of multivariate geostatistical using Cokriging method, a Root Mean Square Error (RMSE) was performed. Estimation result using Cokriging method is good for characterizing the surface physics parameters of radar images data.

Paper ID : 050

Literature Review of Radar Remote Sensing Combined With Continuous GPS Measurements For The Monitoring Of

Deformations Of Geothermal Fields (Jane Mbogo and Josephat Kebu-Kenya Electricity Generating Company)

Jane Mbogo, Josephat Kebu Kenya Electricity Generating Company Ltd.

P.O BOX 785, Naivasha, Kenya jmbogo@kengen.co.ke, jkebu@kengen.co.ke

ABSTRACT

Electricity generation from geothermal sources is associated with geothermal fluid extraction and re-injection, resulting in surface changes/displacements horizontally and vertically (uplift or sinking) (Eneva, 2009). Besides, previous geodetic monitoring of geothermal production sites have shown large subsidence and horizontal displacement attributed to thermal contraction, pressure reduction in the reservoir, and/or changes in the local stress field (Heimlich, Masson, & Gourmelen, 2013). Conventional surveying methods employed to measure the deformations of structures with small and slow displacements have often provided infrequent though precise estimates of these deformations. With the development of high precision GPS methods and Remote Sensing, an alternative method for monitoring structural deformations is available. Continuous GPS measurements technique with its higher temporal resolution is complemented with RADAR remote sensing so as to cover larger areas spatially. Citing case studies, this paper fronts the application of RADAR Remote Sensing complimented with continuous GPS measurements as an ideal way of monitoring deformations of geothermal fields for better geothermal field management. A similar proposition has been forwarded for approval in the management of Olkaria Geothermal Field which houses the largest geothermal power plant in Africa.

46

Paper ID : 051

Repeat Absolute and Relative Gravity Measurements for Geothermal Reservoir Monitoring in Ogiri Geothermal Field, Southern Kyushu, Japan

Jun Nishijima, Chika Umeda, Yasuhiro Fujimitsu, Jun-ichi Takayama, Naoto Hiraga, and Satoru Higuchi

Department of Earth Resources Engineering, Faculty of Engineering, Kyushu University 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan

nishijima@mine.kyushu-u.ac.jp

ABSTRACT Repeat hybrid microgravity measurements were conducted around the Ogiri Geothermal Field on the western slope of Kirishima volcano, southern Kyushu, Japan. This study was undertaken to detect the short-term gravity change caused by the temporary shutdown of production and reinjection wells for regular maintenance in 2011 and 2013. Repeat microgravity measurements were taken using an A-10 absolute gravimeter (Micro-g LaCoste) and CG-5 gravimeter (Scintrex) before and after regular maintenance. Both instruments had an accuracy of 10 µgal. The gravity stations were established at 27 stations (two stations for absolute measurements and 25 stations for relative measurements). After removal of noise effects (e.g., tidal movement, precipitation, shallow groundwater level changes), the residual gravity changes were subdivided into five types of response. We detected a gravity decrease (up to 20 µgal) in the reinjection area and a gravity increase (up to 30 µgal) in the production area 1 month after the temporary shutdown. Most of the gravity stations recovered after the maintenance. The temporal density changes in the geothermal reservoir were estimated based on these gravity changes.

Paper ID : 052

Volcanological Approaching for Evaluation of Geothermal Potential in Galunggung Mountain

Qodri Syahrur Ramadhan, Akhmad Kunio Pratopo, Juni Yesy Sianipar

Magister Program of Geothermal Engineering, Faculty of Mining and Petroleum Engineering, Bandung Institute of Technology (ITB), Jl. Ganesha No. 10, Bandung, Indonesia 40132

qodrisyahrurramadhan@gmail.com

ABSTRACT Geothermal system in Indonesia is associated with volcanoes. There are more than 200 volcanoes that located in Sumatra, Java and Eastern of Indonesia. Studying about the characteristic of volcano, volcanostratigraphy, is one of methods used in early stage for the exploration of volcanic geothermal system. The method is identifying the stratigraphy of volcano from topographic map on Tasikmalaya sheet 1:100.000 on scale, 1:50.000 on scale and also geological map. The schematic flowchart of the evaluation of geothermal exploration is used to interpreted and evaluated geothermal potential in volcanic regions. Volcanostratigraphy study has been done on Mt. Galunggung and Mt. Talaga Bodas, West Java, Indonesia. Based on the interpretation of topographic map and analysis of dimension, rock composition, age and stress regime, we conclude that both Mt. Galunggung and Mt. Talaga Bodas have a geothermal resource potential that deserves further investigations. Keywords: volcanostratigraphy, topographic map, geothermal system.

47

Paper ID : 054

Numerical Model of Unsteady Two-phase Flow in Geothermal Production Well

Keisuke Yamamura, Ryuichi Itoi, Toshiaki Tanaka, Takaichi Iwasaki Department of Earth Resources Engineering, Kyushu University

Fukuoka, Japan ykatayama61@gmail.com

ABSTRACT

Fluctuation of wellhead pressure was observed in a geothermal production well with multiple feedzones. This pressure instability affects stable steam production and stable operation of power plant, which in the worst case may lead to the stop of steam production of the well. Its mechanism, however, has not been well understood. In this study, we developed a numerical model of transient steam-water two-phase wellbore flow. This model can handle an inclined wellbore with different well radius. Simulation results show a good match with the PTS well-logging results. Other parameters such as steam quality and void fraction, density, velocity, and specific enthalpy were analyzed and found to conform the behavior of two-phase flow in the wellbore.

Paper ID : 061

Characteristic of Geothermal Fluid At East Manggarai, Flores, East Nusa Tenggara

Mochamad Iqbal1, Niniek Rina Herdianita

2, Dikdik Risdianto

3

1Geological Engineering, Bandung Institute of Technology

2Applied Geology Research Group, Bandung Institute of Technology

3Center for Geological Resources, Bandung

1iqbalduri@gmail.com

ABSTRACT

The research area is located in East Manggarai and its surrounding area, Flores. The geomorphology of the study area consists of volcanic cones, volcanic slopes, lava dome and undulating hills. The geology of the study area is dominated by Quaternary volcanic products, i.e. lava and pyroclastic rocks. The structural geology developed in the area is relatively trending north-south and northeast-southwest. In the study area there are two geothermal systems, i.e. Mapos geothermal system which is associated with Anak Ranakah volcano and Rana Masak geothermal systems which is associated with Watuweri volcano. The difference within these systems is shown by the relative content of conservative elements of Cl, Li and B. Geothermal surface manifestations in Mapos include 4 hot springs having temperatures of 34,3-51,4

oC and bicarbonate and sulphate-bicarbonate waters; the

discharge area in Rana Masak consist of 3 hot springs with temperatures of 38-46,6oC and chloride and chloride-

bicarbonate water. Stable isotopes 18

O and D analyses showed that the geothermal fluid derived from meteoric water. The Mapos geothermal system is a high temperature system having reservoir temperature of 250-270ºC with natural heat loss of 230 kW. The Rana Masak geothermal system is a low temperature system having reservoir temperature of 120-140ºC with natural heat loss of 120 kW. Keywords: Anak Ranakah, East Manggarai, Flores, geochemistry, geothermal, Watuweri.

48

Paper ID : 062

Performance Analysis of Mineral Mapping Method to Delineate Mineralization Zones Under Tropical Region

Muhamad Hardin Wakila

1, Asep Saepuloh

2, Mohamad Nur Heriawan

1

1Faculty of Mining and Petroleum Engineering, Bandung Institute of Technology (ITB), Jl. Ganesha No. 10, Bandung, West

Java, Indonesia 40132 2Faculty of Earth Sciences and Technology, Bandung Institute of Technology (ITB), Jl. Ganesha No. 10, Bandung, West Java,

Indonesia 40132 wakilamuh.hardin@yahoo.com

ABSTRACT

Geothermal explorations are currently being intensely conducted at several areas in Indonesia; one of them is Wayang Windu area, West Java. Mineral mapping is very important method in geothermal explorations to determine the distribution of minerals which indicate the surface manifestations of geothermal potential in the Wayang Windu. Because the region of Wayang Windu is very wide for direct explorations and objects (minerals) were observed has high homogeneity, it is necessary to mapping with precise and accurate method to determine the distribution of these minerals. This study aims to determine the most precise and accurate methods for minerals mapping on the surface for geothermal manifestations. Field measurements are performed to validate the data or results of the mapping from several methods. The field data that will be targeted include: soil, rock and the fluid samples. The method were examined in this study are: 1) Minimum Noise Fraction (MNF), the linear transformation method which is useful to eliminate the correlation between the band and to reduce the noise in the data until a certain extent, 2) Pixel Purity Index (PPI), a method which is designed to find the most extreme spectrum pixel, and the pixel characteristic which tends to accordance with end-members mix, 3) Spectral Angle Mapper (SAM), a technique of classifying objects in an area (image) by measuring the spectral similarity between an unknown object with spectral reference (known) in n-dimension. The output of this research was mineral mapping from each method; they are MNF, PPI, and SAM, which were compared to the ground truth. The result of research showed that SAM method is the most appropriate and accurate for mineral mapping related geothermal manifestations. Keywords: mineral mapping, geothermal manifestations, Minimum Noise Fraction, Pixel Purity Index, Spectral Angle Mapper

Paper ID : 063

Characteristic of Geothermal Reservoir Based on Analysis of Surface Manifestation, Fluid Geochemical and Rock Alteration; Case Study of Ungaran Volcano Geothermal Area, Central Java, Indonesia

Muhammad Afkarul Haq, Farchan Nauval, Nashir Idzharul Huda

Geological Engineering of Diponegoro University Jl. Prof. Soedarto, Tembalang, Semarang, Indonesia

afkar.haq@gmail.com

ABSTRACT Geothermal prospect area of Ungaran Volcano is located in Central Java Province, Indonesia. This area is one of the most eastern North Serayu mountain range. Gedongsongo, Nglimut, Kendalisodo and Diwak constitute the area by surface manifestation that consist of hot springs, warm ground, warm pool, silica sinter, fumaroles and altered rock. The purpose of this research is to find out the characteristic of geothermal reservoir which could be used as one of the parameter and basic recommendation in planning stage of Ungaran geothermal prospect. The research undertaken by identify structural control of Ungaran geothermal system, analysis of fluid geochemical to find out the temperature and characteristic of fluid phase in reservoir, fluid origin, and also corrosivity and fluid tendency to form solid precipitate. Besides, the research will also interprete about rock alteration on geothermal area. Some of geothermal manifestation in Gedongsongo, Nglimut, Kendalisodo and Diwak could exist on surface caused by major fault control on each area. The hot springs (e.g., Gedongsongo and Nglimut,) are well correlated with high horizontal gradient anomalies that are interpreted as boundaries or faults. Then field observation on Kendalisodo geothermal area shows andesitic intrusion and altered rock on outcrop. This phenomenon could be used as an indication that geothermal system of Kendalisodo area formed by the intrusion itself. Based on analysis of geothermometer and chemical content of fluid, then interpreted that counted average of reservoir temperature could classified into high enthalpy geothermal system, and the characteristic of reservoir’s phase is water dominated. Silica content on fluid phase reservoir is probable to form silica scaling in separated water pipeline and reinjection wells. Keywords: geothermometer, alteration, scaling

49

Paper ID : 065

A Comparison Analysis between Russel James Equation and Hiriart Equation in Horizontal Discharge Lip Pressure for

Production Test at Geothermal Well Using Statistical Method

Muhammad Nizami

Petroleum Engineering Study Program, Institut Teknologi Bandung Jl. Ganesha 10, Bandung, Indonesia

muhammad_nizami@students.itb.ac.id

ABSTRACT Production test is one of very crucial activity in development process of geothermal field. This activity is run after drilling and completion process of well were done. Production test must be run to determine the condition of the well, reservoir characteristic and production capacity of the well and also clean drill cuttings or mud drilling from the well. Production test data should be processed carefully to get more accurate result and approach the actual condition of the well. Currently, there are two methods in production test: lip pressure and separator method. Lip pressure can be performed in an upright (vertical discharge) or in a flat configuration (horizontal discharge). Russel James Equation is usually used when calculating several parameters at lip pressure method. This equation connecting mass flow rate, enthalpy, lip pipe cross-sectional area and lip pressure. Hiriart equation is more simple than Russel James Equation because it only requires pressure and lip pipe diameter as the variables. Hiriart equation neglects the fluid enthalpy parameter, so that the accuracy level is lower than Russel James Equation. This equation is only applied in vapor-dominated geothermal wells. If this equation will be applied in two phase well, it need to be corrected with additional certain parameter. This paper presents a comparison between Russel James equation and Hiriart equation using statistical method. The comparison is conducted by calculating the error value and the standard deviation at 95% confidence level that obtained by the normal distribution curve. To validate result from both equation, it must be generated by calculation using available field production test data. When the result is calculated by Hiriart equation inside acceptance range, this equation can be used to replace Russel James equation because it is more simple equation and easy to use for calculation in production test analysis of geothermal well. Keywords: production test, Russel James equation, Hiriart equation, statistical method

Paper ID : 066

Mathematical Modelling of Silica Scaling Deposition in Geothermal Wells

Muhammad Nizami1, Sutopo

2

1Petroleum Engineering Study Program, Institut Teknologi Bandung

2Geothermal Engineering Study Program, Institut Teknologi Bandung

Jl. Ganesha 10, Bandung, Indonesia muhammad_nizami@students.itb.ac.id

1 , sutopo@tm.itb.ac.id

2

ABSTRACT

Silica scaling is widely encountered in geothermal wells which produce two-phase geothermal fluid. Silica scaling can be formed due to chemical reacting by mixing a geothermal fluid with other geothermal fluid in different compositions, or also can be caused by changes in fluid properties due to changes pressure and temperature. One of method to overcome silica scaling which is occurred around geothermal well is by workover operation. Modelling of silica deposition in porous medium has been modeled in previously. However, the growth of silica scaling deposition in geothermal wells has never been modeled. Modelling of silica deposition through geothermal is important aspects to determine depth of silica scaling growth and best placing for workover device to clean silica scaling. This study is attempted to develop mathematical models for predicting silica scaling through geothermal wells. The mathematical model is developed by integrating the solubility-temperature correlation and two-phase pressure drop coupled heat loss correlation in a production well. The coupled model of two-phase pressure drop and heat loss calculation which is used in this paper is Hasan-Kabir correlation. This modelling is divided into two categories: single and two phase fluid model. Modelling of silica deposition is constrained in temperature distribution effect through geothermal wells by solubility correlation for silica. The results of this study are visualizing the growth of silica scaling thickness through geothermal wells in each segment of depth. Sensitivity analysis is applied in several parameters, such as: bottom-hole pressure, temperature, and silica concentrations. Temperature is most impact factor for silica scaling through geothermal wellbore and depth of flash point. In flash point, silica scaling thickness has reached maximum because reducing of mole in liquid. Keywords: mathematical modelling, silica scaling, silica solubility, well-bore modelling

50

Paper ID : 067

Feasibility of Geothermal Energy Extraction From Non-Activated Petroleum Wells In Arun Field

Muhammad Syarifudin, Kalvin Maurice, Franky Octavius Institut Teknologi Bandung

Jalan Ganesha No.10, Bandung, Indonesia syarifudin@s.itb.ac.id

ABSTRACT

Geothermal energy is very promising renewable energy. Theoretically, it can be harvested from oil/gas wells which satisfy several criteria. Geothermal may provides a stable energy source that has low impact on the environment, if it is properly managed. The big obstacle to develop geothermal is frequently came from the economical viewpoint which mostly contributed by the drilling cost. However, it can be tackled by converting the existing decommissioned petroleum well for geothermal purposes. In Arun Field, Aceh, there are 188 wells and 62% of them are inactive (2013). Theoretically, there is a possibility to convert ex-petroleum well into geothermal well. However, outlet water temperature from this conversion setup will not as significant as the temperature that come out from the conventional geothermal well, it will only range from 60 to 180

oC

depending on several key parameters such as the values of ground temperature, geothermal gradient in current location, the flow inside of the tubes, and type of the tubes (the effect from these parameters are studied). It will just be considered as low to medium temperature, according to Hochstein geothermal well classification. To do the well conversion, pipes inside the well that have been used to lift the oil/gas and replacing them with a curly long coil tubing which act as a heat exchanger that convert the cold water from the surface to be indirectly heated by the hot rock at the bottom of the well in a closed loop system. In order to make power production, the binary cycle system is used so that the low to medium temperature fluid is able generate electricity by using organic fluid. Based on this study, producing geothermal energy for direct use and electricity generation in Arun Field is technically possible. In this study case, we conclude that 2900 kW of electricity can be generated. While for direct use, a lot of local industries in Northern Sumatera may get the benefit from this innovation. Keywords: Geothermal Energy · Combined Cycle · Decommissioned Well · Arun Field

Paper ID : 070

Optimal Geothermal Well Cementing A Case of Olkaria Geothermal Field

Nahashon Karanja Nzioka,

KenGen Olkaria Geothermal projects

P.O Box 785-20117 Naivasha

nnzioka@kengen.co.ke

ABSTRACT Olkaria Geothermal field poses major challenges in cementing of well casings due to the fact that the area is highly permeable, the down hole temperature and pressure is very high and the cement sheath between the annular and casing is prone to strength retrogression due to continuous exposure to high temperatures which are in excess of 250°C. This paper documents our experiences in geothermal well cementing from cement design to job execution and lessons learnt from these experiences. Attempts to fight these challenges have been met with varying levels of success so suggested improvements to the current cement design and practices is also presented. Keywords: Thickening time, ECD (Equivalent Circulating Density), Bearden Consistency Bc, BHCT (Bottom Hole Circulating Temperature), WOC (Wait On cement), Lead Cement, Tail cement

51

Paper ID : 072

The Concept of Steam Field and Geothermal Power Plant (PLTP) Development Plan, Case Study at Mount Rajabasa

Nanda Hanyfa Maulida, Suharno Geophysical Engineering, Engineering Faculty - University of Lampung

Jl. Soemantri Brojonegoro No. 1 Bandarlampung nandahanyfa@gmail.com

ABSTRACT

Energy crisis in Indonesia forces the government to build some new geothermal power plants in various potential areas as soon as possible, including Lampung Province that has a great geothermal potency. To develop geothermal power plant, it takes perfect plans to get maximum production result from the exploration. Therefore, to offer some point of view about developing power plant, we make a basic development concept in Rajabasa geothermal field. The potency of Rajabasa is 220 MWe and at the previous paper (Maulida, 2015), we proposed three development steps for this area, and each step generates 55 MWe with total capacity 165 MWe. At this paper, we proposed another development concept to get maximum capacity (220 MWe). With this concept, all power plants will produce 1734.48 GWh total energy in one year. Keywords: Geothermal, steam field, power plant, Rajabasa

Paper ID : 074

Geothermal Direct Use Development To Optimize Renewable Energy Utilization For Agricultural, Aquacultural And Tourism Activities In Indonesia

Nicolas Jalu Pangesty, Muhammad Dzulfikri Firdaus, Adidanu Saputra

Diponegoro University Jl. Prof. Sudarto, SH. Tembalang, Semarang, Central Java

nicolasjalu39@gmail.com

ABSTRACT Indonesia becomes a blessed country due to a huge natural energy resources, especially geothermal energy. Up to 40% of the world geothermal resources that separated into 312 places in whole area, makes Indonesia the highest potential of geothermal energy. From 28 Gigawatt, the production of this renewable energy just reach 4.7 % utilized based on Pertamina Geothermal Energy’s prognosis in 2015. So, there are a lot of opportunities to develop geothermal energy to increase the utilization of this energy for every aspect of life. Nowadays, Indonesia has been developing direct use implementation for geothermal energy utilization to many kinds of agricultural and tourism cases. Geothermal manifestations on the surface such as hot spring or geothermal wells, etc., can be applied for direct use applications. Generally, the geothermal resources located at the heights or mountains where the agricultural activities and tourism mostly placed. They need heat for their processes and activities, so this is the perfect chances to develop geothermal direct use implementation. The simple utilization of geothermal direct use comes from getting steam from small geothermal wells for spa and hot swimming pool, brine from separator in existing power plant, and produce the heat or steam from traditional shallow geothermal well for mushroom cultivation, copra and cocoa drying. In other cases, direct use can be utilized for palm sugar processing and manipulate the aquaculture environment such as mixing the hot water from geothermal manifestation with fresh water to make the optimal environment for catfish grows. Some area of geothermal energy production, located at the tea plantation, where the heat of steam can be utilized for the drying and withering process of tea leaves. Through the activities of geothermal direct use, can be the simple way to optimize this renewable energy utilization in every opportunity with the easy method, green, and cheap. The advantages are to increase the productivity of agricultural and aquaculture activities, decrease the fuel use, decrease the emission, and decrease the cost of agricultural processing. So, Geothermal direct use is the perfect chance to optimize geothermal utilization and advantages.

52

Paper ID : 075

Geothermal Fluid Characteristic Based on Fluid Geochemistry Analysis, Kepahiang, Bengkulu

Novian Triandanu

(1), Boy Yoseph CSS Syah Alam

(2), Sapari Dwi Hadian

(2), Agil Gemilang R

(1)

(1)Student at Faculty of Geological Engineering Padjadjaran University

(2)Lecturer at Faculty of Geological Engineering Padjadjaran University

Jalan Raya Bandung – Sumedang Km. 21 Jatinangor, Indonesia 45363 triandanu@gmail.com

ABSTRACT

Kepahiang Regency is administratively located in Bengkulu Province with approximately 66.500 Ha wide area. Geographically Kepahiang Regency is located between 101º55’19”-103º01’29”E and 02º43’07”-03º46’48”S. Around this area several geothermal surface manifestation are found and divided into seven groups which consist of hot spring, mud pool, fumarole, and solfatara. Heat source is predicted to be derived from volcanic system of Mt. Kaba. The occurrence of surface manifestations indicate the existence of active geothermal system in earth subsurface. The objective of this study is to characterize geothermal fluid and to estimate subsurface temperature. Thermal fluid characterization is using Cl-SO4-HCO3 and Na-K-Mg ternary diagram. Geothermometry analysis used to estimate subsurface temperature. Surface manifestations found grouped into hot spring, fumarole, solfatara and mud pool. Data plotting at Cl-SO4-HCO3 ternary diagram shows that 1 sample is bicarbonate water, 1 sample is chloride water, 1 sample is sulphate water, 2 samples are sulphate-chloride waters, and 3 samples are dilute-chloride waters. Data plotting at Na-K-Mg ternary diagram shows that almost all samples are immature waters. Geothermometry analysis shows highest subsurface temperature is about 280

oC.

Keywords: Kepahiang, Geochemistry, Geothermal

Paper ID : 079

Geology Structure Identification Based on Polametric SAR (POLSAR) Data and Field Geological Mapping at Ciwidey

Geothermal Field

Ratna Amalia Pradipta1, Asep Saepuloh

1,2, and Suryantini

1,2

1Geothermal Technology Study Program, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung

2Geology Engineering Study Program, Faculty of Earth Sciences and Technology, Institut Teknologi Bandung

ratna_amalia_pradipta@yahoo.com

ABSTRACT Geological structure observation is difficult to be conducted at Quaternary volcanic field. Moreover, the classical problem at tropical region such as intensive erosion, dense vegetation covers, and rough terrain hamper the field scale observation of the geological structures. Overcoming the problems, an active remote sensing technology based on Polarimetric Synthetic Aperture Radar (PolSAR) data was used in this study. The PolSAR data presented in this study is superior to detect Geomorphologics and Structural Features (GSF) under canopy vegetation. The longer wavelength of microwave than optical region caused the SAR penetration capability is higher. The Ciwidey Geothermal Field (CGF) at West Java, Indonesia, was selected as study area because surface manifestations were found without information about surface geological structures. Visual interpretation based on composite polarization modes was applied to identify geological structures at study area. The color composite R, G, B for HV, HH, VV polarizations provided highest texture and structural features among the other composite combination. The Linear Feature Density (LFD) map calculated from total length of linear features per 1 km

2 in the composite PolSAR image was also used to interpret the fractures zones. The identified zones were

used as basis for geological field investigation. Based on visual interpretation of composite PolSAR the direction of main linear features were detected in NW-SE, NE-SW, E-W, and N-S. In addition, the calculated LFD showed high anomaly about 3.7 km/km

2 with two strike directions NW-SE and NE-SW. Interestingly, the surface geothermal manifestation agreed with

the low anomaly of LFD, about 0.6-1.8 km/km2. High erosional level caused by hydrothermal fluid obliterated the trace of

structures. Cross section relationship observed from visual structural features and LFD were used to construct geological structure mechanism. The geological structures consisted of 10 faults were detected and mapped successfully. The faults type mainly oblique-slip with strike directions are NE – SW and NW – SE. The detected fault directions were similar with regional faults. Therefore, geology structure mechanism at study area agreed to the regional tectonic mechanism.

53

Paper ID : 081

The Effectiveness of Hydrothermal Alteration Mapping based on Hyperspectral Data under Tropical Region

1Reyno Rivelino D. M.,

1,2Asep Saepuloh

1Geothermal Technology Study Program, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung

2Geology Engineering Study Program, Faculty of Earth Sciences and Technology, Institut Teknologi Bandung

reynorivelino@gmail.com

ABSTRACT Reflectance spectra in the near- and shortwave infrared region offer signature response for determining the mineralogy of rocks and soils. Hyperspectral remote sensing could be used to characterize the targets at earth’s surface based on their spectra. This capability is useful for mapping and characterizing the distribution of host rocks, alteration assemblages, and minerals. Contrary to the multispectral sensors, the hyperspectral identifies targets with high spectral resolution. The Wayang Windu Geothermal field in West Java, Indonesia was selected as the study area due to the existence of surface manifestation and dense vegetation environment. Therefore, the effectiveness of hyperspectral remote sensing under tropical region was targeted as the objective of this study. The Spectral Angle Mapper (SAM) method was used to detect the occurrence of clay minerals spatially based on hyperspectral data from Hyperion. The SAM references of reflectance spectra were obtained from field observation at altered materials. To calculate the effectiveness of hyperspectral data, we used multispectral data from Landsat 8. The comparison method was conducted by comparing the SAM’s rule images from Hyperion and Landsat 8 with field observation. The mineral mapping based on hyperspectral is more accurate than multispectral data. Hyperion SAM’s rule images showed lower value compared to Landsat 8. The significant number derived from using Hyperion was about 24% better than Landsat 8. This inferred that the hyperspectral remote sensing is preferable for mineral mapping even though vegetation covered study area. Keywords: Reflectance, Hyperion, Landsat 8, Wayang Windu, Tropic.

Paper ID : 083

Energy Optimization Modeling of Geothermal Power Plant

(Case Study : Darajat Geothermal Field Unit III)

Rizal Sinaga1, Prihadi Setyo Darmanto

2

1Engineering Management Study Program, Del Institute of Technology, Laguboti, Toba Samosir, Indonesia

2Mechanical Engineering Study Program, Bandung Institute of Technology, Bandung, Indonesia

rizal.sinaga@del.ac.id

ABSTRACT Darajat unit III geothermal power plant is developed by PT. Chevron Geothermal Indonesia (CGI). This power plant has capacity 121 MW on load 110%. The greatest utilization power is consumed by Hot Well Pump (HWP) and Cooling Tower Fan (CTF). Wet bub temperature fluctuation provides opportunity for energy optimizing of those equipments. Optimization of HWP and CTF utilization is applied using Variable Frequency Drive (VFD) and modeling was generated by Engineering Equation Solver (EES) commercial version 9.430. This model was validated by Process Flow Diagram (PFD) Darajat unit III and modeling process was reviewed trough Specific Steam Consumption (SSC) nett. Result shows that present operation reaches its optimum condition and VFD application may be applied if both HWP and CTF operated in frequency 60 Hz.

54

Paper ID : 090

Volcanostratigraphy for Supporting Geothermal Exploration

Sutikno Bronto

1, Juni Yesy Sianipar

2, Akhmad Kunio Pratopo

2,

1 Geological Agency, Ministry of Energy and Mineral Resources,

57th Diponegoro Rd., Bandung 40122, Indonesia, sutiknobronto@gmail.com

2Student of Master Program in Geothermal Technology, Faculty of Mining and Petroleum Engineering, Institute of

Technology Bandung. Jalan Ganesha No. 10, Bandung, Indonesia

junisianipar91@gmail.com

ABSTRACT Volcanostratigraphy is stratigraphy relating to volcanism and its products. This covers stratigraphy for general scope applied in regional area, and detailed matter in local area. On the basis of Indonesian Stratigraphic Code 1996, from low to high rank, volcanostratigraphic units are Hummock (Gumuk), Crown (Khuluk), Brigade (Bregada), Super Brigade (Manggala), and Arc (Busur). In more detailed stratigraphic study those units can be divided into genetic rock units based on source location, proccesses, and absolute age classification. Genetic proccesses include transportation and cooling or deposition mechanisms. These lead to physical- and chemical properties of volcanic rocks and imply history of geovolcanisms and geothermal proccesses as important data in geothermal exploration. Key words: volcanostratigraphy, hummock, crown, brigade, super brigade, arc, geothermal exploration

Paper ID : 091

Gravity Modeling and Second Vertical Derivative Calculation to Analysis Subsurface Structure at Wayratai Geothermal

Prospect Area, Lampung

Taufiq(1) (1)Geophysical Engineering Department, Engineering Faculty, University of Lampung

Soemantri Street No.1, Bandar Lampung taufiqgeophysics76@gmail.com

ABSTRACT

Wayratai Geothermal Prospect Area, Lampung is near a cluster of Mount Ratai with geological condition in the form of young volcanic sediment such as lava, breccias, and tuff obtained from the eruption of Mount Ratai. To determine geothermal potential in Wayratai area, we needed some preliminary surveys such as geological, geochemistry, and geophysical survey. Based on geological mapping, we obtained several point of manifestations such as 5 hotspring points (with a temperature 86-90°C), mudpool, steaming ground, and alterated rock. Afterthat, performed with a geophysical survey using the gravity method to determine subsurface structure and describe the initial conditions of the geothermal system. Gravity method is used because this method is sensitive to analyze the vertical changes, and can describe the subsurface conditions based on density variation of rock. Based on data acquisition and literature studies performed on Wayratai geothermal prospects area, obtained 2D and 3D subsurface model based on density variations. From the model, obtained area with a density value 2.3-2.6 gr/cm

3 and depth from 400 to 2000 m were assumed to be a reservoir zone.

Then, the area with a density value 2.8-3.2 gr/cm3 and depth from 2000-2500 m assumed to be a heat source. With these

density, we can assume that the rock in reservoir area is calcareous-breccia and in the heat source is an andesitic-basaltic rocks. Based on the analysis of second vertical derivative calculation, obtained value of SVD maximum is greater than SVD minimum which indicated that the area is a basin structure or normal fault, and its strenghtening of the assumption that the modelling of the geothermal reservoir is graben form. Keywords : geothermal prospect, gravity, second vertical derivative, structure

55

Paper ID : 093

Estimation of Geothermal Speculative Resource Potential Using Geochemistry Method in East Manggarai Regency, East

Nusa Tenggara Province

Teguh Rahat PRABOWO1, Muhammad Ghassan Jazmi SHALIHIN

1, Aton PATONAH

1, Fithriyani FAUZIYYAH

2, Andri Eko Ari

WIBOWO3

1 Undergraduate Study Program Faculty of Geology, Universitas Padjadjaran, Indonesia

2 Master Study Program Faculty of Earth Science and Technology, ITB, Indonesia

3 Pusat Sumber Daya Geologi, Ministry of Energy and Mineral Resource, Indonesia

teguhprabowo_23@yahoo.com

ABSTRACT Geothermal is an alternative energy that improving in Indonesia and has great potential in Indonesia. But the problem is the lack of exploitation. So the goverment conduct intensive exploration to several area in Indonesia. One of the area that become focus in this exploration is East Manggarai, East Nusa Tenggara. East Manggarai is mostly consisted by volcanic rocks from young volcano such as Mt. Ranaka. This research is an early survey as the first step. The object in this research are hot springs as geothermal ground manifestation, they are Mapos, Wae Lareng, and Ulu Galung hot spring. According to the research result, Mapos-Wae Lareng hot spring types are sulfate and bicarbonate while Ulu Galung hot spring type is sulphate. And if we see the reservoir, Mapos hot spring and Wae Lareng hot spring have the same reservoir. To support the geochemistry experiment on the hot waters, research on Hg in the soil is conducted so we can achieve the potential speculative area. And if it combined with geothermometer data we will achieve that the geothermal speculative resources potential for Mapos-Wae Lareng is 57 Mwe and for Ulu Galung is 0,3 Mwe, which mean that Mapos-Wae Lareng area is more potential for further research than Ulu Galung.

Paper ID : 095

Geophysical Exploration For Geothermal Low Enthalpy Resources In Ungaran Regency, Central Java

Udi Harmoko1, Hiska Anggit M.

2, Gatot Yulianto

1, Sugeng Widada

3, Yusuf Dewantoro Herlambang

4

1) Geophysics Laboratory, Faculty of Science and Mathematics, Diponegoro University

2)Geophysics Master student of Physics Department of University of Indonesia, Indonesia

3) Department of Oceanography, Faculty of Fisherises and Marine Sciences, Diponegoro University

4) Department of Mechanical Engineering, Semarang State Polytecnic

Prof.Soedarto St., Tembalang, Semarang, Indonesia udiharmoko@fisika.undip.ac.id

ABSTRACT

In an effort to further advance understanding of Diwak-Derekan geothermal system, the next geophysical survey has been carried out extended to the southern area covering Kaliulo, Jatikurung and Kendalisodo geothermal hot springs. The magnetic residual anomalies have been reproduced especially on the southern part of the main study area. 3D magnetic analysis and direct current ground resistivity measurement using schlumberger array allowed us to evaluate the subsurface structure of the sites. Based on magnetic field anomaly and the in situ geological data, a speculation shows that magnetization intensity assumed for the existence of a cooling magma intrusion is suggested at the southern part of the study area that is located at Sajen Village.

56

Paper ID : 096

Quantitative Comparison of Two 3-D Resistivity Models of the Montelago Geothermal Prospect

W.A. van Leeuwen

1, Suryantini

2, G.P. Hersir

3

1IF Technology, Velperweg 37, 6813DP Arnhem, the Netherlands

2Institut Teknologi Bandung, Jl. Tamansari 64 Bandung 40116, Indonesia

3Iceland GeoSurvey (ÍSOR), Grensásvegur 9, 108 Reykjavík, Iceland

w.vanleeuwen@iftechnology.nl

ABSTRACT A combined TEM-MT survey was carried out in the Montelago geothermal prospect, situated on Mindoro Island, the Philippines, with the aim to obtain the dimensions and depth of the geothermal reservoir as well as to formulate the prospects’ conceptual model. The acquired MT data are static shift corrected using the TEM measurements. Two different 3-D inversion codes are used to create subsurface resistivity models of the corrected MT data set. The similarities and differences between the two resistivity models are quantitatively assessed using a set of structural metrics. Both resistivity models can be generalized by a three-layered model. The model consists of a thin heterogeneous, conductive layer overlying a thick resistive layer, while the basement has a decreased resistivity. Although this is a common characteristic resistivity response for the alteration mineralogy of a volcanic geothermal system, the temperatures at depth are lower than would be expected when interpreting the modelled resistivity model accordingly. Since the last volcanic activity in the area was about one million years ago, it is anticipated that the resolved resistivity structure is a remnant of a hydrothermal system associated with a volcanic heat source. This model interpretation is validated by the alteration minerals present in the exploration wells, where high temperature minerals such as epidote are present at depths with a lower temperature than epidote’s initial formation temperature. This generalized description of the resistivity model is confirmed by both resistivity models. In this paper the two inversion models are not only compared by assessing the inversion models, but also by reviewing a set of gradient based structural metrics. An attempt is made to improve the interpretation of the conceptual model by analyzing these structural metrics. Based on these analyses it is concluded that both inversions resolve similar resistivity structures and that the location of the two slim holes drilled are well chosen.

Paper ID : 097

Resistivity Method for Hydrothermal System Analyze in Way Ratai Geothermal Field

1Anggraeni Widia,

1Setyadi Bagas

1Geophysical Engineering, University of Lampung

Bandar Lampung 35145, Indonesia widiageofisika@gmail.com, bagasetyadi@live.com

ABSTRACT

Geothermal is one of the geological resources that potentially for renewable energy, geothermal characterized by the appearance of hot spring and steaming ground (hydrothermal) in surface of the earth. This research purpose to determine the model of the geological subsurface in Way Ratai Hydrothermal system based on resistivity measurement data by geoelectrics resistivity method. Ares Resistivitymeter Type 850 with Schlumberger configuration is used in this research. As the results of measurements data are modeled in the cross-section of 2D and 3D model. The results of interpretation indicate that hydrothermal intrusion zones and the distribution of hot water flow in subsurface is showed in the zones with resistivity values less than 4.5 Ωm. The correlation of the manifestation point with 3D model, that represent every manifestation in this research area is comes from a hydrothermal system interrelated one each other, this phenomena are associated with geological condition in the Way Ratai Geothermal Field.

57

Paper ID : 098

Experimental Study of Isothermal Plate Uniformity For Blood Warmer Development Using Geothermal Energy

1)

Y. Ichsan 2)

J. Hendrarsakti 1)

Faculty of Mechanical and Aerospace Engineering 2)

Geothermal Master Program Institut Teknologi Bandung

Jalan Ganeca No 10 1)

yaumil.ichsan@students.itb.ac.id 2)

jooned@ftmd.itb.ac.id

ABSTRACT This research was conducted to assess the direct use of geothermal energy for blood warmer. The heating plate was made form aluminum plates with dimensions of 100 x 200 mm and then fed from the hot water heater. Tests were conducted in the laboratory where geothermal source water is replaced with the heat generated from the heater. The hot water from the heater in the temperature range 55 °C - 60 °C flowed into vertical chamber. Setting the temperature of the hot water heater is done by changing the flow of hot water coming out of the heater. Results showed that the value of a standard deviation of plate temperature was about 0.42 °C, so it can be said isothermal accordance with design requirement and objective. The test data used for the analysis of the manufacture of the heating plate in the blood warmer to regulate the discharge of hot water at intervals of 21.47 mL/s to 24.8 mL/s to obtain a temperature of 37.20 °C – 40,15 °C. Geothermal energy has the potential for blood warmer because blood warmer is part of the energy cascade in a temperature range of 40 °C to 60 °C. Keywords: direct use, geothermal energy, temperature, debit, blood warmer

Paper ID : 099

Electricity Generation from Hydrothermal Vents

Yuzar Aryadi 1, 3

, Imam Saiful Rizal 1, 4

, Muhammad Nur Fadhli 2, 5

1 Department of Petroleum Engineering,

2 Department of Mechanical Engineering, Institut Teknologi Bandung

Bandung 3

ujaraziz@gmail.com ; 4

imamsr4@gmail.com ; 5 muhammad.nurfadhli@ymail.com

ABSTRACT

Hydrothermal vent is a kind of manifestation of geothermal energy on seabed. It produces high temperature fluid through a hole which has a diameter in various range between several inches to tens of meters. Hydrothermal vent is mostly found over ocean ridges. There are some 67000 km of ocean ridges, 13000 of them have been already studied discovering more than 280 sites with geothermal vents. Some of them have a thermal power of up to 60 MWt .These big potential resources of energy, which are located over subsea, have a constraint related to environmental impact to the biotas live around when it becomes an object of exploitation. Organic Rankine Cycle (ORC) is a method of exploiting heat energy to become electricity using organic fluid. This paper presents a model of exploitation technology of hydrothermal vent using ORC method. With conservative calculation, it can give result of 15 MWe by exploiting a middle range diameter of hydrothermal vent in deep of 2000 meters below sea level. The technology provided here really has small impact to the environment. With an output energy as huge as mentioned before, the price of constructing this technology is low considering the empty of cost for drilling as what it should be in conventional exploitation. This paper also presents the comparison in several equipment which is more suitable to be installed over subsea. Keywords: ORC, Hydrothermal Vent, Subsea.

58

Paper ID : 101

Minigeo : Small Scale Geothermal Power for Remote Off-Grid Communities

N. Willemsen, MSc. J. H. Kleinlugtenbelt, MSc. Drs A. Willemsen IF Technology

Velperweg 37, Arnhem The Netherlands

n.willemsen@iftechnology.nl

ABSTRACT This paper is a first feasibility scan of a small-scale off-grid geothermal power station based on low/medium enthalpy geothermal resources. As a counterpart to Minihydro we call this system MiniGeo. The goal is to replace diesel generator sets commonly found in areas not covered by conventional power grids. This study found several benefits from using the MiniGeo system in off-grid areas that have suitable geology. These include: Lower energy costs, reliable and controllable power supply, combined heat and power production, no CO2 emission and small land usage. The downside is that almost all costs are made upfront and a suitable geology is required. For suitable geological locations the Levelized Cost of Energy (LCOE) is around $0,10- $0,20/kWh. Almost half that of power from pv-battery systems and a third the cost of power made from diesel generators.

Paper ID : 104

Design of Tomato Drying System by Utilizing Geothermal Brine

W. Afuar1, B. Sibarani

1, G. Abdurrahman

1, J. Hendrarsakti

1,2

1Geothermal Master Program ITB, Bandung, Indonesia

2 Faculty of Mechanical and Aerospace Engineering ITB, Bandung, Indonesia

waldyafuar@gmail.com

ABSTRACT Cultivation of tomato plants in Indonesia has been started since 1961.Tomatoes generally will rot in three days if left on storage. Moreover, low quality tomatoes have cheaper price. After harvested, tomatoes need to be treated by drying process so it can last longer. Energy for drying tomatoes can be obtained by utilizing heat from geothermal brine. Purpose of this research is to design a tomato drying system by extracting heat of geothermal brine from separator with certain flow rate to heat up water by using a heat exchanger. Furthermore, this water will be used to heat up the surrounding air which is circulated by blower system to heat up the tomatoes chamber. Tomatoes drying process needs temperature range of 50-70 °C to evaporate water content from 95.7% to 26%. After that treatment, the tomatoes are expected to have better durability. The objective of this study is to determine the quantity of hot brine which is needed for drying tomatoes and to design a drying system so that tomatoes can last longer. Keywords: tomato dryer, geothermal brine, heat exchanger, direct use.

59

Paper ID : 107

Geological, Isothermal, and Isobaric 3-D Model Construction in Early Stage of Geothermal Exploration

Mahesa Pradana Saputra

1, Suryantini

2, Danilo Catigtig

3, Riky Regandara, Sitti Nur Asnin, Angga Bakti Pratama

1,2 Graduate Program in Geothermal Technology, Faculty of Mining and Petroleum Engineering

2Engineering Geology Study Program, Faculty of Earth Sciences and Technology

Institut Teknologi Bandung, Bandung 40132, Indonesia 3

Emerging Power Inc., Philippines 1

mahesa.nawie@gmail.com, 2 suryantini@gc.itb.ac.id,

3dccsedan@gmail.com

ABSTRACT Construction of geology, thermal anomaly and pressure distribution of a geothermal system in the early stage of exploration where data is limited is described using a 3-D software, Leapfrog Geothermal. The geological 3-D model was developed from a topographic map (derived from DEM data), geological map and literature studies reported in an early geological survey. The isothermal 3-D model was constructed using reservoir temperature estimation from geothermometry calculated from chemical analyses on surface manifestations, available shallow gradient temperature hole data and the normal gradient temperature (3°C/100m) for a non-thermal area. The isobaric 3-D model was built using hydrostatic pressure where the hydrostatic pressure is determined by the product of the fluid density, acceleration due to gravity, and depth. Fluid density is given by saturated liquid density as a function of temperature. There are some constraints on the modeling result such as (1) within the predicted reservoir, the geothermal gradient is not constant but continues to increase, thus, creating an anomalously high temperature at depth, and (2) the lithology model is made by interpolating and extrapolating cross-sections whereas usually only two to three geology sections were available for this study. Hence, the modeler must understand the geology. An additional cross section was developed by the modeler which may not be as suitable as the geologist constructed sections. The results of this study can be combined with geophysical data such as gravity, geomagnetic, micro-tremor and resistivity data. The combination of geological, geochemical, isothermal, isobaric and geophysical data could be used in (1) estimating the geometry and size of the geothermal reservoir, (2) predicting the depth of top reservoir, and (3) creating well prognosis for exploration and production wells. Keywords: 3-D Model, Leapfrog Geothermal.

Paper ID : 111

Occurrence of Sarawet Hot Spring : What Affects the Outflow?

Windi Anarta Draniswari1, Rezki Naufan Hendrawan

1

1Geological Engineering, Master Program, Bandung Institute of Technology

1draniswari@gmail.com

ABSTRACT

Geothermal systems located in volcanic arc are generally influenced by volcanic activities. But at the complex geological setting like Sulawesi the geothermal systems probably is not only influenced by volcanic activities but also structural geology features. Our study shows that the surface geological-structural analysis in combination with the geochemistry and the heat flow investigation is the essential tools for geothermal systems or manifestation characterization. Tectonics, crust characteristic, heat flow, and surface structural figure could affect the manifestations and its geothermal systems. Sarawet hot spring in Minahasa is a kind of volcanic-influenced and fault-influenced manifestations. Sarawet hot spring is located in north coast Minahasa. Geochemically the water is bicarbonate, peripheral-immature water, and characterized by a meteoric water-line trend. The composition of these thermal springs was controlled by a secondary process during ascent. Based on hydrologic gradient, heat flow characteristic and subsurface structural analysis, the mechanism of Sarawet hot spring is a lateral outflow that affected by dynamically maintained fractures system. Keywords : Sarawet, volcanic and fault influenced, lateral outflow

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Paper ID : 112

The Cooling History Of Residual Magma As Heat Source

I G.B. Eddy SUCIPTA and Isao TAKASHIMA* Department of Geology, Faculty of Earth Sciences and Technology, Bandung Institute of Technology, Jl. Ganesha 10

Bandung – 40135, INDONESIA, sucipta@gc.itb.ac.id

*Emeritus Professor at The Research Institute of Material and Resources, Akita University,1-1 Tegata gakuen-machi, Akita-shi, Akita 010-8502 JAPAN, takasima@ipc.akita-u.ac.jp

ABSTRACT

The Bajawa Geothermal Field is located on the island of Flores, Indonesia. This area could be one of the most prospective geothermal area on Flores island, consist not only of such numerous active volcano as Inerie and Inie Lika but also potential geothermal manifestations as Wolo Bobo, Nage, Mataloko and Mengeruda. The Bajawa Geothermal Field related to the Bajawa Cinder Cone Complex that their volcanic rocks displayed the heating of andesite magma by invading the higher temperature and more mafic magma (basaltic magma) in their magma chamber. The basaltic magma have temperature range of 1056

0C-1164

0C based on the Fe-Ti oxides temperature. There are three

batches of magma with the two magma recharge in the long life of the Bajawa Cinder Cone Complex at the 0.73 Ma to 0.14 Ma which the magma mixing and fractional crystallization are the important processes in differentiation of magma. The magma mixing have done in the early crystallization of each magma batches and then after well mixing the magma have been doing a normal fractionation crystallization. The cooling history of residual magma in the magma chamber of the Bajawa Cinder Cone Complex is approximately 3.025

0C/1000 years (302.5

0C/0.1 Ma) between 0.23 Ma to 0.14 Ma and then changed approximately of 2.429

0C/1000 years

(242.90C/0.1 Ma)

from 0.14 Ma to the present time.

Paper ID : 114

Classifying Hot Water Chemistry: Application Of Multivariate Statistics

Prihadi Sumintadireja1, Dasapta Erwin Irawan

1, Yuano Rezky

2, Prana Ugiana Gio

3, Anggita Agustin

1

1Faculty of Earth Sciences and Technology, Institut Teknologi Bandung, Jalan Ganesa No. 10, Bandung 40132

2Dirjen EBTK

3Faculty of Math and Natural Sciences, Universitas Sumatera Utara, Jl. dr. T. Mansur No. 9,

Medan 20155 dasaptaerwin@outlook.co.id

ABSTRACT

The following paper is a try out on the application of multivariate analysis (regression tree, principal component analysis, and cluster analysis) for classifying hot water chemistry. The number of sample analysed was 11 (including three cold-water samples), taken from three Gorontalo geothermal sites (Boalemo, Pohuwato, and Gorontalo Regency. Regression tree technique has failed to read the data structure due to collinearity effect therefore PCA and cluster analysis were applied. We used open source R statistical packages to do the calculation. Such technique classifies hot water samples into three major clusters: cluster 1 (hot water from Diloniyohu-Boalemo), cluster 2 (combining hot water from Tungo and Dulangeya-Boalemo, and cold water from Dulangeya-Boalemo), and cluster 3 (cold water from Pohuwato and Diloniyohu-Boalemo). According to the results, hot water from Boalemo consists of systems: distinct geothermal system and mixing system with meteoric water, while hot water from Pohuwato has no or less mixing with meteoric water. The statistical is able to detect the close and open geothermal system based on data structure. This robust method should be applied to more geothermal system with larger dataset to see its performance.

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Paper ID : 115

Resource Management using Numerical Modeling and Apparent Productivity Index

William L. Osborn1, Dennis Kaspereit

1, William Rickard

1, Mary Mann

1 and Magdalena Perez

2

1 Geothermal Resource Group, 77530 Enfield Lane, Bldg. E, Palm Desert, CA 92211

2 Momotombo Power Company, Reparto Las Cumbres, Casa D13, Managua, Nicaragua

wosborn@geothermalresourcegroup.com mperez@mpc.com.ni

ABSTRACT Numerical simulation is most commonly used to evaluate the current and future generation potential of geothermal reservoirs. However, a well-calibrated numerical model can also be used to identify deficiencies in the conceptual model, in addition to well bore and formation damage. Using a numerical model calibrated by detailed history matching, an apparent productivity index, or analogous apparent injectivity index, can be calculated for the production history of each well in the field. The resulting apparent productivity index trend can then reveal formation-related losses in productivity or injectivity. Difficulty in achieving as suitable history match, based on assumed well conditions, may reveal potential well damage. We use a revised conceptual model and numerical simulation of the Momotombo geothermal field to demonstrate the utility of these tools for identification of several common wellfield problems. Within the history matching process of the numerical model, two downhole well bore failures were identified.

Paper ID : 116

A Collaborative Engineering Approach To Achieve Success In Geothermal Drilling Application

Yudi Indrinanto, Manuel Centeno Acuna, William Thomas, Michael Ari Dhanto, Agus Ziyad Kurnia, Erik Gunawan

Supriatna, Bonar Noviasta, Donny Trias Ardianto, M.R. Yoan Mardiana Schlumberger

Beltway Office Park, Building C, 6th

Floor, Jakarta Selatan, Indonesia yudi.indrinanto@starenergy.co.id, MAcuna@slb.com, WThomas4@slb.com, MDhanto@slb.com, AKurnia2@slb.com,

ESupriatna@slb.com, BNoviasta@slb.com, DTArdianto@slb.com, MMardiana@slb.com

ABSTRACT With the current downturn of the oil business, geothermal projects remain stable and will ramp up in line with the Indonesian government commitment to provide 35,000 MW electricity by 2019. After 5 years absence in geothermal business, Schlumberger is putting back its footprints in the geothermal business by providing an integrated drilling services to Star Energy, one of the main geothermal key players in Indonesia. A collaborative engineering approach was performed by different drilling segments in Schlumberger to produce an integrated planning, execution, and evaluation to achieve a safe and successful drilling operation. Schlumberger integrated drilling services delivered a successful drilling operation that enabled Star Energy to achieve an actual production level exceeding the planned production.

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Paper ID : 117

Analysis on Scaling Problem in Injection Line: A Case from Muara Labuh Geothermal Field, Indonesia

Alfiady1, Robi Irsamukhti

1, Alfianto Perdana Putra

1, Herwin Azis

1 and Jantiur Situmorang

1

1Supreme Energy, Menara Sentraya, 23

rd Floor Jl. Iskandarsyah Raya No. 1A Kebayoran Baru, Jakarta 12160

alfiady@supreme-energy.com

ABSTRACT Scaling was observed in the injection pipe line during the long term production tests conducted near the end of the exploration drilling program at the Muara Labuh Geothermal field. The scaling significantly reduced the ability of the injection line to transfer the produced brine to the assigned injector, constraining the production well to be flowed at maximum opening condition. XRD and Petrography analysis of the scale samples shows the scale consists of mainly Halite (Sodium Chloride; NaCl) with negligible silica (<5%). Apparently, the open injection system created alot of evaporation which led to Halite precipitation. While, silica - in the form of amorphous silica- is normal to precipitate in brine pond due to a significant brine fluid temperature drop. In-situ solubility test on the scale samples provided confirmation that Halite is soluble in fresh water. Therefore, a treatment of pumping fresh water through the scaled pipe line was conducted and successfully restored the injection capacity.

Paper ID : 118

A Preliminary Research Of Direct Contact Geothermal Steam Condensation In The Presence Of Non Condensable Gas

Vivi Apriyanti

1*, Willy Adriansyah

1, Ari D. Pasek

1, Y.B. Agastyo Nugroho

2, Candra M. Sufyana

2, Abdurrachim

1

1Faculty of Mechanical and Aerospace Engineering, Institut Teknologi Bandung

2Geothermal Master Program, Institut Teknologi Bandung

Jl. Ganesa 10, Bandung 40132, Indonesia viviapriyanti@students.itb.ac.id

ABSTRACT

Condenser is an important equipment at a steam power plant. Vacuum pressure in the condenser is generated during the process of condensation gives greater difference in enthalpy of the turbine, thus increases producing of electrical energy output. In geothermal power plants steam coming from the well always contain non condensable gasses (NCG). The content of non condensable gas and the temperature of cooling water are two parameters that varied and difficult to control. NCG concentration depends on the condition of wells plants, while the cooling water temperature is determined by the temperature of the air around the plant and the cooling tower performance. The presence of non condensable gasses is believed will decrease the heat transfer rate in the condensation process compared to the pure water vapor. Not many information yet available in the literature for direct contact condensation heat transfer of water vapor in the presence of non condensable gas. In this research water will be sprayed into saturated steam containing a small amount of CO2 and condensation heat transfer coefficient will be investigated. The design of experimental set up and the construction of equipment such as condensation chamber, steam generator, CO2 tank, mixing chamber of steam and CO2 and the assesories has been done recently. CO2 concentration will be varied between 0 to 4% and the condensation will be run at atmospheric and vacuum pressure. Parallel to this work a numerical simulation is on going. The numerical result and experimental result will be compared and reported. In this paper, relevant researches are reviewed and construction for heat transfer condensation experimental set up in the presence of NCG is presented. Keywords: non condensable gas, direct contact condensation, heat transfer rate

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Paper ID : 119

A Comprehensive Well Testing Implementation During Exploration Phase in Rantau Dedap, Indonesia

Muhammad Tamrin Humaedi, Alfiady, Alfianto Perdana Putra, Rudy Martikno, Jantiur Situmorang

PT Supreme Energy Sentraya Tower 23rd Floor. Jl. Iskandarsyah Raya 1A, Kebayoran Baru. Jakarta 12160 - INDONESIA

tamrin-humaedi@supreme-energy.com

ABSTRACT This paper describes the implementation of comprehensive well testing programs during the 2014-2015 exploration drilling in Rantau Dedap Geothermal Field. The well testing programs were designed to provide reliable data as foundation for resource assessment as well as useful information for decision making during drilling. A series of well testing survey consisting of SFTT, completion test, heating-up downhole logging, discharge test, chemistry sampling was conducted to understand individual wells characteristics such as thermodynamic state of the reservoir fluid, permeability distribution, well output and fluid chemistry. Furthermore, interference test was carried out to investigate the response of reservoir to exploitation.

Paper ID : 121

Performance Prediction of Two-Phase Geothermal Reservoir Using Lumped Parameter Model

Famelia Nurlaela and Sutopo

Master Program of Geothermal Technology, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung

Jalan Ganeca 10, Bandung, 40132, West Java, Indonesia famelia.nurlaela@gmail.com and sutopo@tm.itb.ac.id

ABSTRACT

Many studies have been conducted to simulate performance of low-temperature geothermal reservoirs using lumped parameter method. Limited work had been done on applying non-isothermal lumped parameter models to higher temperature geothermal reservoirs. In this study, the lumped parameter method was applied to high-temperature two phase geothermal reservoirs. The model couples both energy and mass balance equations thus can predict temperature, pressure and fluid saturation changes in the reservoir as a result of production, re-injection of water, and/or natural recharge. This method was validated using reservoir simulation results of TOUGH2. As the results, the two phase lumped parameter model simulation without recharge shows good matching, however reservoir model with recharge condition show quite good conformity.

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Paper ID : 122

Use Of Sub-Terrain Technology In Geothermal Exploration

George Barber1)

and Madjedi Hasan &

, Anton Wahjosudibjo

2)

1) Indonesia International Energy Solution Partners (IEP)

2) Pranata Energi Nusantara (PENConsulting)

ABSTRACT

Similar to oil and gas undertaking, geothermal exploration, development, and operations are costly and also subject to uncertainties, which vary among different geothermal reservoirs. However, while in oil and gas exploration, the potential can be identified with reasonable confidence prior to drilling through the utilization of available geophysical techniques, they are not as effective and do not provide the same level of confidence in defining geothermal reservoirs. In exploration, risk in the form of time, expense and success are a given. The key is to manage the risk effectively, which means that we need to use all the tools that are available in the modern explorer’s toolbox, which includes traditional and unconventional methods. In order to provide a catalyst for the explorer and investor to bring their capital, the catalyst should be in the form of confidence building data and indications of prospects. Technology is part of the answer for successful exploration to find resources; the technology should be able to dramatically reduce the time, cost and risk before applying more expensive traditional exploration tools such as seismic and exploratory drilling. By pre-staging conventional exploration with unconventional tools, one focuses precious exploration finances on high-probability targets, which in turn will achieve higher returns on investment. This paper will discuss the potential application of Sub Terrain Prospecting (STeP®) technology as tools of confirmation in geothermal undertaking to supplement the conventional exploration tools. STeP® is a proprietary, remote sensing and analytical technology of Terra Energy & Resource Technologies which interprets and quantifies various natural phenomena manifests at the surface using sophisticated algorithms and models, such phenomena being directly linked to subsurface geological features. STeP® technology includes multi-spectral satellite data analysis, which in contrast to other Remote Sensing methods provides not only horizontal distribution of thermal anomalies but also vertical/cross-sectional geo-informational anomalies, together with structure-metric analysis, reflecting the structure in both horizontal and vertical planes over the target area. STeP® technology has evolved over the past 30 years with many successful projects having been carried out in various parts of the world. STeP® can improve the exploration success rate, reduce the time from years to months, and reduce the risk of exploratory survey and drilling costs. Pre-staging exploration should drive significant investment for the governments geothermal development plans for Indonesia, whilst at the same time decreasing the time, cost and risk.

Paper ID : 129

Natural State Modelling in Hululais Geothermal Field Based on Exploration Data

Pudyo Hastuti, Sutopo and Marihot Silaban Pertamina Geothermal Energy, ITB

ABSTRACT

Hululais geothermal field is located in the province of Bengkulu, Indonesia and operated by PT Pertamina Geothermal Energy (PGE). The field development plan has been initiated through exploration activities since 1994. Hululais are now entering the stage of development with three exploration wells for planning of 2 × 55 MW plant. This field is expected to be commercial in early 2018 and 2019. Evaluation and reservoir modeling is required to determine and predict the ability of the reservoir during the term of the contract including the number of production and injection wells to be drilled. The model will be run in various production scenarios in order to obtain optimum reservoir management strategy. The results of the modelling and simulation of the reservoir at the natural state conditions showed a good enough matching for the temperature and pressure data of three exploration wells. Distribution of pressure and temperature also have compatibility with the the flow pattern at conceptual model which the flow of fluid move from Suban Agung and Mount Beriti toward the north where the reservoir temperature about 260 - 300 °C with top of reservoir located at an elevation of 0 meters above sea level. Control structures play a huge role in the pattern of fluid flow in the field of Hululais. The movement of the fluid which is controlled by the structure of the NW-SE trending si confirmed by the well HLS HLS A-1 and C-1. Keywords: reservoir simulation, natural state, forecasting, Hululais

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Paper ID : 131

Assessment Thermal Flow Direction of Geothermal Manifestation Based on Temporal Analysis of Temperature Distribution at Pine Forest Park, Tomohon, North Sulawesi

Cyrke A. N. Bujung

1), Donny R. Wenas

2)

1,2) Physics Department FMIPA Manado State University

e-mail: cyrkebujung@yahoo.com 1)

, roy.wenas@yahoo.com2)

ABSTRACT The presence of geothermal energy resource subsurface is reflected on the surface by the appearance of geothermal manifestation, i.e. hot spring, hot mud, fumaroles, etc. Existence of surface geothermal manifestation occurred as consequence thermal propagation from subsurface by fractures as geothermal fluid medium to surface. This research describes the surface temperature distribution and to know thermal direction based on temporal analysis of temperature distribution at pine forest park, Tomohon North Sulawesi. This research apply the remote sensing methods with thermal infrared channel recorded in years 2013, 2014, and 2015. The result of research shows that thermal anomaly, and thermal flow direction of geothermal manifestation at pine forest park trend toward northeast. Keywords: Thermal flow direction, geothermal manifestation, temporal analysis.

Paper ID : 132

Influence of Hydrothermal Alteration on Petrophysical Properties of Rocks in the Cibolang Area, Bandung

Arif Susanto , Suryantini1, Imam A. Sadisun1, Asep Saepuloh1, Noriyoshi Tsuchiya2 1Geological Engineering Study Program, Faculty of Earth Sciences and Technology, Institut Teknologi Bandung, Indonesia

2Graduate School of Environmental Studies, Tohoku University, Japan arifs@gc.itb.ac.id

ABSTRACT

The Cibolang Area, southern part of the Wayang Windu geothermal field is situated in the West Java province of Indonesia are covered by volcanic rocks of Wayang-Windu Volcanic Complex. Some surface manifestation as solfataras, hot springs and an intensive hydrothermal alteration present in this area. Thermal vapour and water altered and transformed volcanic rocks into hydrothermal rocks. Volcanic rocks as andesite, pyroclastic breccia and tuff altered into argillic and advanced argillic alterations. Based on petrographic, X-ray diffraction and SEM analyses, the mineralogical alteration consist of kaolinite, halloysite, alunite, illite, cristobalite, pyrite and sulphur. Petrophysical properties depend mainly on rock primary features (composition, structure, grain size, heterogeneity) and hydrothermal alteration. Clay minerals of rocks decrease in shear strength along with other petrophysical properties that promoting the slope instability and triggering landslides.

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Paper ID : 133

Contamination of Thermal Water to Groundwater in Kertasari Area, Bandung

Arif Susanto , Suryantini1, Joshua Satriana1, Munib Ikhwatun Iman2, Noriyoshi Tsuchiya3

1 Geological Engineering Study Program, Faculty of Earth Sciences and Technology, Institut Teknologi Bandung, Indonesia

2 Center of Groundwater Resources and Environmental Geology, Geological Agency, Indonesia

3 Graduate School of Environmental Studies, Tohoku University, Japan arifs@gc.itb.ac.id

ABSTRACT

The Kertasari Area, eastern part of the Wayang Windu geothermal field is situated in the West Java province of Indonesia. Some surface manifestation as solfataras, hot springs and an intensive hydrothermal alteration present in this area. Hydrogeochemical study was conducted to find out contamination of thermal water to groundwater in Kertasari Area and interpretation eastern boundary of Wayang Windu Geothermal System. Thermal and cold springs samples were collected from two hot springs, three warm springs and five cold springs, subjected to physical properties, major cation and anion, also isotope analyses. Result of this study shows that cold springs of Situ Kinceu, Cikoleberes and Citawa-2 experiencing increase of temperatures, total dissolve solid (TDS), sulphate and bicarbonate content, while pH decreasing that suggested contaminated by thermal water. The contaminated of cold spring confirmed by SO42- and HCO3- anion increasing range from three to five times than local meteoric water The geothermal system boundary is estimated between thermal spring or contaminated cold spring with uncontaminated cold spring.

Paper ID : 134

On the Feasibility of Geothermal Heat Production from A Hot Sedimentary Aquifer : A Case Study of the Jababeka

District, West Java

Nurita Putri Hardiani, Setya Drana Harry Putra Geothermal Master Program of Institut Teknologi Bandung

Jl Ganesha No 10, Bandung nurita_putri@yahoo.co.uk; setyadrana@gmail.com

ABSTRACT

This study describes an approach taken for understanding the technical feasibility of geothermal heat extraction from a Hot Sedimentary Aquifer (HSA) reservoir. A numerical modelling technique is employed that allows for reliable prediction of changes to the target reservoir’s production behaviour based on their sensitivity to variations in a number of physical parameters. The present study considers the effects of the modelled reservoir’s permeability, aquifer thickness, production-reinjection well spacing, production flow rate, and reinjection temperature to be evaluated. An HSA reservoir that constitutes a part of the greater onshore North West Java Basin and presumably underlies the Bekasi Regency area is selected as a case study. The region is also of a great interest due to the numerous types of industry it currently hosts, most of which are likely candidates for future applications of direct geothermal energy utilization from sedimentary basins. In addition, past petroleum resource exploration activities has provided significant information that is used to constrain the reservoir modelling procedure to a certain extent. It is demonstrated that the results obtained by carrying out the systematic methodology proposed in this study are sufficiently reliable for use in predicting the feasibility of proposed thermal energy extraction schemes for the HSA reservoir underlying the study area. It is shown that the HSA reservoir evaluated in this study is predicted to be capable of producing a 150°C hot fluid for 150 years.

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Paper ID : 135

Geology and Prospecting for Hidden Geothermal System of Manglayang Volcano Complex of Bandung-West Java

Subandrio, AS*., Sumintadireja, P*., Irawan, D* and Suryantini *Program Studi Teknik Geologi – FITB -ITB

ABSTRACT

Manglayang Volcano Complex (MVC) is the Quarternary volcanic cone in the northern part of Bandung area, one of the examples of an active subduction zone in southern of West Java. Widespread volcanism has been active in this region in the Late Pleistocene, producing large volumes of lavas and pyroclastics covering a narrow belt, across the southern Lembang zone, from the Palasari in the western to Manglayang .Three major evolutionary stages have been identified in the evolution of the MVC: pre-eruption, post-eruption and late stages. The pre-eruption stage is further differentiated into effusive, extrusive and explosive phases, the latter being responsible for the lava and pyroclastic formation. The products of this stage cover a compositional range from basalts to andesite, and consist of lava flows and associated pyroclastics. The post-eruption stage consists of three phases comprising presumably phreato-magmatic eruptions. The late stage consists of the explosive and the following effusive phases with pyroclastic flow, respectively. The major and trace element systematics, along with petrographic evidences, suggest clinopyroxene + plagioclase ± olivine ± amphibole as the major fractionating phases governing the liquid evolutionary paths, with a progressive increase in the proportions of plagioclase and amphibole in the fractionating assemblages during the course of magmatic differentiation. The other purpose of this study was also to appraise the feasibility of finding hidden geothermal systems in the MVC using geoelectrical tomography methods. The results were used to try to estimate what a suite of geophysical surveys of the prospect would see. In this paper, we review the recently exploration on MVC and the results of the theoretical studies. We suggest that a suite of electrical surveys together with shallow heat flow surveys and relevant local geological and hydrogeological observations offers a promising approach to the identification and preliminary characterization of hidden geothermal systems.

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