Geothermal Energy Options Elim,...
Transcript of Geothermal Energy Options Elim,...
GGeothermal Energy Options Elim, Alaska
Gwen Holdmann / Chris Pike / George Roe
Discussion Items
ACEP Introduction Background on geothermal energy Local hot springs resource Possible applications Next steps (discussion)
Role of ACEP and the University of Alaska Developing information for decision makers
o Technology testing and optimization (industry) o Energy analysis (policy makers, communities)
Preparing students to work in energy-related disciplines
Commercializing energy innovation
BBoth in the laboratory and in the field Recent lab-based examples include: Electratherm, Sustainable Automation grid-forming inverter, Prudent Energy flow battery, Williams flywheel (next up)
Testing and System Optimization
ACEP Energy Technology Lab (L) and Premium Power Installation in Kotzebue (R)
Using Organic Rankine Cycle technology for waste heat recovery
Example: Geothermal Industrial Process Energy
Electratherm 50kW ORC System
Pratt & Whitney 280 kW ORC System
Electratherm testing at UAF
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ACEP Projects are Statewide Islanded electric grid integration River hydrokinetics Low temperature geothermal Remote sensing/thermal imaging Waste heat utilization Coal-to-liquids technology Biomass energy Transmission and distribution Fuel additives assessment Small modular nuclear reactors Advanced energy storage Ground source and seawater source heat pumps Stranded renewable resources assessment Waves resource assessment
Cosmos, August 2008
OurENERGY.com
Production/Injection Well Flow Diagram
Production Well Injection Well
© Geothermal Education Office 2000
How Geothermal Power is Generated
Heat Exchanger
GeneratorTurbine
R134a Refrigerant
Reinjected Geothermal
Water
Geothermal Water (from production well)
Binary Power Plant Technology
Geothermal EnergyThe two highest temperature geothermal resources outside the Alaska Peninsula and Aleutians are located on the Seward Peninsula
Pilgrim Hot Springs
Serpentine Hot Springs
ACEP Geothermal Resource Assessments
NNome/Pilgrim Chena Hot Springs Manley Hot Springs Tenakee Hot Springs Granite Mountain
Shungnak Akutan Adak Atka Elim
Granite Mountain Resource Assessment
Funded by NANA through WH Pacific
Shungnak Resource Assessment
Tenakee Springs Resource Assessment
ACEP been involved in multiple aspects of assessing geothermal energy as an option for Nome, including an extensive resource assessment, economic analysis, fuel pricing, and integration with existing generation sources. In collaboration with: AEA, US DOE, Unaatuq, BSNC, NSEDC, the City of Nome and NJUS, SNC, WMNC, TNC, MINC, USGS
Pilgrim Hot Springs Resource Assessment
Clockwise from left: ACEP shallow drilling program; confirmation drilling program in 2013, community meeting in Teller; thermal mapping of region.
Images from Chena Hot Springs Resort
Low-temp geothermal – direct use
CCase studies
Tenakee Springs
Community-use soaking tub Geothermal heating of changing room and nearby warehouse 2013-2013 refurbishment by local volunteers and community donations with Rasmuson Foundation support
Direct Use: Pool – Hot Tub - Bathhouse
Images & information from: http://www.tenakeehistoricalcollection.org/bathphotos/
Temperature at source:~140 F
Natural flow from spring:70 gpm
¼ mile of on-ground insulated 4-inch PVC pipe
Gravity feed, no pump required
After the water is used for heating, it is discharged into its natural drainage area.
Direct Use: Space Heating
White Bear Hot Springs
Geothermal water is piped to remote 1970’s era multi-room cabin and used for space heating
District energy system Began as source of heat for school Eventually expanded to other community buildings and swimming pool
Direct Use: Space Heating
Midland, South Dakota
Lund, J., J. Nemec, and R. Vollmer. "Midland, South Dakota geothermal district heating." TRANSACTIONS-GEOTHERMAL RESOURCES COUNCIL (1998): 15-18.
The waste geothermal water is used to water cattle, before being released into the Bad River at the edge of town.
Tolovana Hot Springs Wilderness site 45 miles northwest of Fairbanks Accessible by trail, bush plane and canoe
Meyer’s Farm Bethel, Alaska
Provides the local community with fresh organic vegetables Short term volunteers work at the farm for room and board Uses a combination of raised beds and greenhouses
Geothermal Heat for Aquaculture
Farming tropical fish and alligators in Idaho for food and hides.
Geothermal Heat For Fish Drying
Drying fish, seaweed, and kelp for export in Iceland
Fish drying in 1977
Using geothermal heat to dry fish
LLocal hot springs resource and possible applications
Hot springs nearest to Elim
Clear Creek Temperature:
Surface: 145-153 F High sub-surface: 171-196 F
Natural flow rate: 211 gpm Distance by trail: 17 miles
Elim Hot Springs Temperature:
Surface: 104-122 F High sub-surface: 158 F
Natural flow rate: 22 gpm Distance by trail: 11 miles
Elim
What is local knowledge of hot spring flows? How have they been used before?
Hot springs energy use at Elim
From http://www.ga.gov.au/image_cache/GA10661.pdf (accessed 24 March 2014) adaptation of Lindal, B. (1973) Industrial and Other Applications of Geothermal Energy.
Pool / Hot tub / Bathhouse Greenhouse Mushroom growing Food-drying Aquaculture Space heating Water pre-heating Heat-driven refrigeration
Could the resource be developed for power generation? How hot is the resource?
Kwiniuk – geothermometer indicates 70°C (158F) Clear Creek – 77 to 91°C (max 195F) Chena – 120 to 128°C (262F) Pilgrim 135 to 145°C (293F)
Assume Clear Creek is tapped for power generation Back of the envelope calculations (truly)
Clear Creek – 77 to 91°C (max 195F) Assume generate 150kW, using 200gpm of 165ºF fluid Transmission line costs $250k/mile x 17miles = $4.25M Drilling and power plant construction ~$5M (wild guess) Energy storage? Interconnection? $1M Total cost ~$11M Elim power sales ~1.1M kWhrs/year, fuel portion of electricity cost is 35cents/kWhr
• WWild estimate of total cost is $11M • Assume we displace all diesel generation • Savings is $385,000 per year • Simple payback is ~30 years
Should water be piped to Elim? Back of the envelope calculations (truly)
Clear Creek source, (165 ºF, 200 gpm, 200 days/year) On-ground piping cost: 175,000 $/mile 17 mile pipeline Additional costs for infrastructure build out at both ends Elim uses ~105,000 gallons of diesel fuel for heating annually; assume offset about 65,000 gallons
• 33 M$ for pipeline only …. $7M total likely • 735mMbtu thermal energy • Possible uses: pre-heating, district heat • Value annually assuming $6 fuel = $310k • Payback is ~22 years
“Direct use” of hot springs energy
Pool / Hot tub / Bathhouse Greenhouse Mushroom growing Food-drying Aquaculture Space heating Water pre-heating Heat-driven refrigeration
“Direct use” of hot springs energy
Clear Creek (65 C)
Kwiniuk (45 C)
From http://www.ga.gov.au/image_cache/GA10661.pdf (accessed 24 March 2014) adaptation of Lindal, B. (1973) Industrial and Other Applications of Geothermal Energy.
Possible next steps Community meeting to assess interests & preferences regarding use of the hot springs Assemble locally-available information about hot springs (e.g., thermal conditions, pictures, usage history, trails) Collect additional thermal samples and map ‘hot spots’ identified locally Assess interest in school-related data gathering / pilot study Develop preliminary design concepts and cost estimates for community areas of interest
Gwen Holdmann: 907-474-5402 / [email protected] Pike: (907) 888-3850 / [email protected] Roe: 206-454-9189 / [email protected]
For more information contact:
acep.uaf.edu
SSupplemental Information
CCommunity information
Photo source: http://dcra.commerce.alaska.gov/PHOTOS/Elim/ELIM15.JPG
Community data
Population: approximately 350 Economy
Subsistence: fish, seal, walrus, beluga whale, reindeer, moose Cash: commercial fishing (39 permits), government offices, school, small businesses
Affiliations Federally-recognized tribe: Native Village of Elim Non-ANCSA Property ownership & mineral rights Regional non-profit corporation: Kawerak
Climate
Subarctic climate with maritime influences Summers: Cool and moist, 46 to 62 F average Winters: Cold and dry, -8 to +8 F averagePrecipitation averages: Rainfall 19 in/yr, Snowfall 80 in/yr Norton Sound ice-free mid-June through mid-November Permafrost at some locations in region
Elim Energy Data
Electricity - FY 2013 residential & community facility 60¢/kWh (19 ¢/kWh after PCE)
Diesel-generated: 1,190,778 kWh 92,012 gallons of fuel at 3.90 $/gal Fuel cost: $358,794
Heating Boiler-in-a-Box biomass Heating oil Residential firewood
Critical infrastructure
Aniquin School City Building Elim Native Store (two locations) Post Office / IRA Office Mukluk Telephone / TeleAlaska Building Johnny’s Corner Store GCI Water Treatment Plant Fire Department Health Clinic
Airport Well House Tank Farm AVEC Power Plant Septic Tank Head Start City Shop Church Boys & Girls Club Library Corporation Building
From Elim Hazard Impact Assessment, HDR Alaska, Inc., February 2012 .
Economic Dev’t Plan Priorities 1. New Water Source 2. Develop Rock Quarry 3. Water & Sewer to 4 New Homes 4. Community Building (Old High School) 5. Utilize Our Timber 6. Build Small Boat Harbor 7. Economic Development – Mineral, Geothermal, Hydrothermal 8. Teen Center 9. NSEDC Community Energy Fund (CEF) 10. Replace Old Bridge
As identified in Elim Local Economic Development Plan: 2012-2017; Kawerak, Inc.; 25 April 2013.
Changing the fluid temperature that is used for heating could affect the amount of baseboards a building requires
Traditional boilers generally circulate fluid at about 180 degrees F As a general rule of thumb, in order to circulate 140 degree F fluid, about twice as much baseboard could be needed to achieve the same amount of heat output
Space Heating Retrofit Considerations
Greenhouses
What crops to raise? Local use and/or external market Fresh and/or preserved (can, dry)
Growing conditionsSunlight, irrigation, fertilizer, soil, temperature, humidity, ventilation Pest & disease control
Simple design with active on-site care Cooperative or private or …?
Piping considerations Routing options: on-surface or buried Pressure drop: siphon or pumped Heat loss: insulated (how much, if any) Costs: materials, shipping, installation, energy for operation, maintenance Ground stability Interference with community & wildlife use
Soil considerations for pipe routing
Permafrost Frost heave Hydraulic conductivity Bedrock depth ErosionStability Future use
Miscellaneous considerations
Hot spring attributes: temperature, flow rate, seasonal variation Permitting Surface / ground water flows & storage Effects on local plants and wildlife Pipeline costs (material, installation, repair) & losses (pressure, heat) Energy requirements (pumps, treatment) Maintenance (filters, line repair, quality test) Permafrost impact
Elim-area hot springs chemistry
Key Drilling Equipment
A tracked drill rig would likely be needed to navigate unimproved trails.
Drill bits designed to penetrate dirt and rock
Drill rod is connected to feed the bit into the hole
Casing (approx. 6” in diameter) is required to line the hole once it is drilled
Possible Drilling Steps
Transport rig, drill rod, casing and other equipment to the drill site. Other equipment could include mud system, heavy equipment and so forth. Proceed to drill hole; for a small diameter hole, an exploration hole could likely be turned into a production hole by running casing onto the hole if temperature and flow are suitable.
Other considerations include accommodations for workers, logistics for the delivery of supplies on site, and getting equipment across streams if necessary.
An example of a larger drilling operation at Pilgrim Hot Springs
Cooperative Extension Service
Main website: www.uaf.edu/ces NW CES office: Kari van Delden 907-443-2320 [email protected]
2014 Publications & Media Catalog •Agriculture and Horticulture •Community Resource and Economic Development •Energy Education and Housing •Health, Home and Family Development •Points of Contact, Websites, Other Resources
Tenakee Springs
Surface temperature: 103-106 F Flow rate: TBD gpm Long time community-use soaking tub with oil-heat dressing room Updated in 2012-3 as community volunteer effort + Rasmuson Foundation Tier 1 Community Grant: Cleared / collected seeps, refurbished tub, replaced oil furnace with water-heated floor in dressing room (selectable gravity or pumped flow), added floor heat to adjacent warehouse building
Direct Use: Pool – Hot Tub - Bathhouse
Images & information from: http://www.tenakeehistoricalcollection.org/bathphotos/
Temperature at source:~140 F
Natural flow from spring:70 gpm
¼ mile of on-ground insulated 4-inch PVC pipe
Gravity feed, no pump required
After the water is used for heating, it is discharged into its natural drainage area.
Direct Use: Space Heating
White Bear Hot Springs
Geothermal water is piped ¼ mile to remote 1970’s era multi-room cabin and used for space heating
Population: 250 Began as source of heat for the school and eventually expanded to other community buildings and a swimming pool Initially in 1960’s, the well was drilled on a hill outside of town. Later in 1969 a well was drilled next to the school. Temperature at source: 152 F Flow rate: 180 GPM Well flows high pressure artesian, no pump needed. 30,000 square feet heated around town
Direct Use: Space Heating
Midland, South Dakota (1/2)
Lund, J., J. Nemec, and R. Vollmer. "Midland, South Dakota geothermal district heating." TRANSACTIONS-GEOTHERMAL RESOURCES COUNCIL (1998): 15-18.
Geothermal water is divided into high pressure (100 PSI) and low pressure (~20 PSI) lines. Fluid runs through PVC pipe. The high pressure line uses 80 GPM and loses 7 deg F as it heats the buildings
The low pressure line uses 3 GPM and loses 25 deg F
The waste geothermal water is used to water cattle, before being disposed of into the Bad River on the edge of town.
Midland, South Dakota (2/2)
PPilgrim Hot Springs – Status
Why Low-Temp Geothermal is Economic in Alaska (versus Iceland)
High eenergy costs (typically over 50cents/kWhr in rural areas)
Non-integrated electric grid (communities have their own generation sources)
Cold climate (improves cycle efficiency)
Innovative Geothermal Exploration Techniques
Optical and infrared (FLIR) camerasPotential for rapid, low-cost mapping and quantitative assessmentFunded through DOE and State of AlaskaVerification using standard geothermal exploration techniques
100m
April 2011 – Airborne FLIR (1m pixels)
Church
Pilgrim Hot Springs
Images from Chena Hot Springs Resort
Nome, AK: Pilgrim Hot Springs
Nome Energy Facts
.37/kW
Integration Modeling for City of Nome
How does 2 MW of geothermal generation interact with existing wind and diesel generation sources?
Is this project economic under reasonable cost projections?