The Nexus between Oil and Gas & Renewables in the Energy FutureChad AugustineNational Renewable Energy Laboratory

September 28th, 2017Golden, CO

“…Until recently, the most successful and largest geothermal power developers in the world were oil and gas companies for this fundamental reason: oil and gas

companies are accustomed to, and know how to manage and reduce subsurface and drilling risks. “

Oil & Gas and Geothermal: A Natural Fit?

- Forthcoming DOE GeoVision report

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Geothermal vs. Petroleum – a Comparison

Petroleum Geothermal

300-350°F is “Hot”(150-175°C) Temperature 300-650+°F

(150-350+°C)

5,000 bpd/well is “High Flow”(150 gal/min per well) Flow Rates 50,000 bpd/well is average

(1,500 gal/min per well)

Vertical and Long Reach Horizontal Onshore/Offshore

5”-7” diameter production intervalDrilling

Vertical/DeviatedOnshore

8”-12” diameter bottom hole

High Initial Flow (months)Declining Rate (years)

Production Profile/Timeframe

Constant Production20-30+ Years

Sedimentary Lithology Volcanic/Intrusive/Metamorphic

Stratigraphic/Structural Facies Complex Fault-Dominated

Petroleum (Oil & Gas)~$50/barrel oil

Recovered Product& Value

Heat (Hot Water)~$0.25/barrel hot water

Graphic by Chad Augustine, NREL

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Geothermal Resources

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Types of Sedimentary Geothermal Projects:1. Co-Production with Oil

and Gas Operations2. Retrofit or Re-Purpose

Petroleum Wells3. Drill New Wells

Specifically for SedGeo project

What is Sedimentary Geothermal?

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• Uses existing petroleum operations: water coproduced during oil and gas production

• Surface presence only Examples:• Rocky Mountain Oilfield

Test Center (RMOTC) – 2008• Denbury, MS Demo

(Electratherm/GCGE)• Univ. North Dakota Demo

(CLR Davis Water Injection)

Co-Production with Oil and Gas Operations

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• Take ownership of and use existing petroleum infrastructure – mainly wells –to produce (primarily) geofluids

• Potentially modify wells to optimize generation of geofluidso Rework wellso Access water-bearing

zones that were previously isolated

Examples• Pleasant Bayou Demo,

Brazoria, TX

Retrofit Existing Petroleum Wells

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• Identify and develop sedimentary geothermal resource target formation

• Drill and complete new wells into formation, built-for-purpose wells designed for geofluid productiono Target specific

formation(s)o Large diametero Enhance well productivity

Examples• Unterhaching, Germany• Landau, Germany

Sedimentary Geothermal with New Wells

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Enhanced Geothermal System (EGS) Conceptual Model

• Technology Transfer: Adapt hydraulic fracturing techniques to creating EGS reservoir

NATIONAL RENEWABLE ENERGY LABORATORY 10

Formations for Compressed Air Storage:• Salt Domes

- Huntorf, Germany (1978)- McIntosh, AL (1991)

• Porous SedimentaryFormations

• Depleted Shale Gas Fields

Compressed Air Energy Storage (CAES)

NATIONAL RENEWABLE ENERGY LABORATORY 11

Why Shale Gas Formations?

1. Reduce risk of creating a new underground air storage cavern2. Solar and wind resources are co-located with hydraulically

fractured (fracked) wells

NATIONAL RENEWABLE ENERGY LABORATORY 12

Why Shale Gas Formations?

Fracked well (red dots) density near Greeley, CO, in 2013. Locations of well pads and wellbores

around DFW Airport showing multiple horizontal wellbores per well pad

NATIONAL RENEWABLE ENERGY LABORATORY 13

1. Use or adapt existing/depleted petroleum infrastructure for geothermal production

2. Use existing petroleum knowledge and skills to develop new geothermal plays

3. Use or adapt existing petroleum technologies for geothermal

Oil & Gas/Geothermal Nexus - Opportunities

Extra Slides

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What is Geothermal?

Geothermal Heat Pumps/Ground Source Heat Pumps

Use relatively constant temperature of the earth as heat sink/source for commercial/residential heating and cooling

• Near ambient temperatures (~40-80°F)

• Shallow depths -trenches to wells hundreds of feet deep

Direct Use Geothermal

Use thermal energy (heat) from the earth directly for heating/cooling buildings, greenhouses, aquaculture, pools, spas, etc.

• Moderate temperatures (100-300°F)

• Wells hundreds to thousands of feet deep

Geothermal Power (Electricity Generation)

Use thermal energy (heat) from the earth to generate electricity

• High temperatures (>300°F)

• Wells hundreds to thousands of feet deep

• Baseload generation

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Low Temperatures Large Flow Rates

Adap

ted

from

Aug

ustin

e an

d Fa

lken

ster

n(2

014)

, SPE

-163

142

RMOTC

Denbury

UND

Unterhaching

Pleasant Bayou

Landau

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Production Well Flow Rate Requirements vs. Temperature

Adap

ted

from

Aug

ustin

e an

d Fa

lken

ster

n(2

014)

, SPE

-163

142

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Geothermal Power from Oil Field Water Supply Wells

Hot brine from wells may be used to generate electricity using facilities with Organic Rankin Cycle technologies.

Will Gosnold leads a University of North Dakota Partnership with Continental Resources, Access Energy, Olson Construction, Basin Electric Cooperative, and Slope Electric Cooperative. Project details include:

• Project is located at Cedar Hills Field, which is a water flood EOR operation in Rhame, ND.

• 2 hz water supply wells produce 98C, 51 kg/s, 3000 ppm TDS water from the Lodgepole formation.

• Access Energy delivered two 125 kW ORC units to the site, & power production commenced Apr 2016.

• An analysis indicates the Madision, Red River and Bakken formations could yield sufficient water to be economic for co-produced electrical power. Source: 2016 SMU presentation by

will.gosnold@engr.und.edu