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O.1 Thermal Load Demand in the U.S.
O.2 Direct Uses in the U.S.
1.1 Big Picture Resource Potential - low T resource / Geothermal Prospector
1.2 What's required to identify a play - State and Regional Plays
1.3 State and Regional Geothermal Data from geothermaldata.org
2.1 The Importance of Shifting Exploration Models
2.2 Bounding Parameters for Direct Use of Low-T Geothermal Resources
2.3 District Heating
2.4 GeoExchange - the "other" Geothermal
3.1 Integrated Use of Geothermal Energy and Biomass at Cornell
3.2 Desalination
3.3 Building the Future Grid
3.4 Industrial Applications
3.5 Cascading Uses and Coupling of Technologies
4.1 Renewable thermal Energy Policy
4.2 Direct-Use Profitability: The Economics of Direct Use Geothermal Systems (GEOPHIRES)
4.3 Sharing Resources with Geothermal Distributed Energy Systems
4.4 Business Models - Community Partnerships
4.5 Community Collaboration in Geothermal Direct Use

Date:     June 11, 2015
To:     Arlene Anderson, DOE Geothermal Technologies Office (GTO)
           Tim Reinhardt, DOE Geothermal Technologies Office (GTO)
CC:     Tom Williams, Wendy Harrison
From:     Kate Young
Subject:     Direct Use Geothermal Workshop Summary
                  March 18, 2015, Golden, CO

Summary of information from the presentations and the notes taken by hired CSM students.

Keynote Speaker: Michael McReynolds (Colorado Energy Office)
Geothermal is an emerging technology. We would like to see focus on data analysis to help reduce the up-front risk. Given the large amount of geothermal resources (and researchers) in the state, it would also be helpful to put a pipeline of projects together.

Overview

O.1 Thermal Load Demand in the U.S.

Koenraad Beckers and Maciej Lukawski, Cornell University

Presentation

Presentation summarized the thermal demand in the U.S. by temperature (from 20-260°C) and by use (e.g. pool, space heating, clothes drying). Summary of conclusions include:

  • Total thermal demand is 33.5 EJ (31.7 quads), though 34% is lost in conversion from electricity to heat; only 22.1 EJ (21.0 quads) is actually consumed as heat. (note that not all thermal supply comes from electricity)
  • 50% of the U.S. thermal energy under 260°C is consumed in the residential sector.
  • 45% of the U.S. energy demand (excluding transportation) is consumed as heat below 260°C; 24% of U.S. primary energy demand is consumed as heat below 120°C.
  • Space and water heating around 50°C is the dominant thermal energy use.
  • Geothermal resource temperatures match demand, and depths are not deep in many places.
  • Picture of the U.S. thermal demand hasn't changed much since 1968.

Discussion

  • Some questions arose that were not able to be answered, including:
    • What is the current source of energy used to meet this thermal demand? This analysis has not yet been conducted (that anyone knew of).
    • How much of this demand could be met by geothermal direct use? Some high-quality resource maps have been made and are available on the NGDS, but no analysis has been done to date that quantifies this potential and relates its spatially to demand.

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O.2 Direct Uses in the U.S.

Toni Boyd, OIT

Presentation

Presentation summarized the different types of direct uses (e.g. district heating, greenhouses) in the U.S. including characteristics of each application and current locations of deployment. Summary of conclusions include:

  • No "specialty" equipment is necessary for development; uses conventional water-well drilling and other off-the-shelf equipment.
  • Direct use uses fluids from 38-150°C, though 85% are below 93°C. This overlaps with the high-demand (14+ EJ) temperature range (<100°C) identified in the previous presentation.
  • Top states include California (105.1 MWt), Idaho (94.3 MWt), Oregon (77.8 MWt) and Nevada (74.8 MWt)
  • Currently 615.9 MWt total is being supplied in the U.S. from geothermal;
  • As a percent, geothermal direct use supplies 0.042% of the U.S. thermal load demand (based on demand numbers from previous presentation).
  • Map identifying 404 resources that are >50°C and are located within 5 miles of a community.

Discussion

  • The biggest problem in developing projects is that most communities don't realize they have the resource and/or how to utilize it.
  • Many of these applications have variable load demands. These are handled by regulating flow rates.
  • Geo-heat Center was one of the best clearinghouses of data.
  • There is, perhaps, potential (though how much isn't known) to reduce the heating demand by moving the need for the heat below ground.
  • Analysis provided does not currently included the use of geothermal heat pumps.

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Session 1: Direct Use Potential

1.1 Big Picture Resource Potential - low T resource / Geothermal Prospector

Chad Augustine and Dan Getman, NREL

Presentation summarized DOE tools that could be used to analyze direct use resource potential, including:

Discussion

  • Prospector contains some (but not all) heat flow data. Other heat flow data can be easily loaded from the NGDS directly into Prospector.
  • Prospector provides the ability to look at technical data. Since there are so many variables that go into an economic analysis (including things like complex reservoir models), it wouldn't really be feasible to have Prospector provide an economic analysis.

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1.2 What's required to identify a play - State and Regional Plays

Brian Anderson, WVU

Presentation discussed district heating potential in various regions including: ID, WV, NY, PA. Summary of conclusions include:

  • Feasibility of district heating depends on three things: climate (days heating/cooling required), geothermal resource (drilling cost), and population density (demand profiles, piping costs).
  • Over 800 district heating systems in the U.S. (not necessarily geothermal, but some can be) -- operating for >100 years.
  • Development of LCOH supply curves for district heating use many analyses, including resource assessment, demand assessment, GIS mapping, economic assessments (Geophires), and surface cost assessments.
  • Supply curves for geothermal district heating and cooling in the U.S. have been developed by He. X. and Anderson, B.J. (2014).

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1.3 State and Regional Geothermal Data from geothermaldata.org

Arlene Anderson, GTO

Presentation

Presentation showed detailed resources maps and data pertinent to direct use that are available on the National Geothermal Data System a.k.a. NGDS (geothermaldata.org), including Alaska, Arizona, Arkansas, California, Colorado, Connecticut, Delaware, Florida, Hawaii, Idaho, Illinois, Indiana, Kansas, Louisiana, Maine, Maryland, Minnesota, Missouri, Montana, Nebraska, New Hampshire, New Jersey, New York, North Dakota, Ohio, Pennsylvania, South Dakota, Tennessee, Texas, West Virginia.

Discussion

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Session 2: Exploration and Direct Geothermal Uses in the U.S.

2.1 The Importance of Shifting Exploration Models

Jerry Smith, Pagosa Waters, LLC

Presentation

Presentation summarized the benefits of implementing direct use at low temperatures, as well as Pagosa Waters' strategy for exploration, fundraising and community support in Pagosa Verde, Colorado. High-level conclusions include:

  • Shifting the focus of exploration from power to heat opens up more opportunities for development.
  • Investor classes for conventional power development are banks, financial institutions and individuals. Direct-use projects can attract additional investors -- such as states and community/local governments -- whose interests include jobs, economic development and recreational benefits. Appealing to each investor class' interests increases opportunity.
  • Heat-only projects (when compared to low-T binary power plants) create more jobs (17/1), smaller up-front investment (1/1.3), and shorter payback periods (1/2).
  • This model (direct use) appeals to the local community as it directly benefits them with food and heat.

Discussion:

  • "How do we get from a point where someone on their property has a well that is potential to where there is resource enough for development? How do they drill wells, and how is that scaled down with the high-temperature version? Is there a potential resource there, and how can we use it?"
    • You have to approach the drilling process economically, figure out what exactly you can use the heat for for each particular area.
    • It is important to have community support to start with or the project won't move forward.
    • Use online databases, choose protocols carefully, approach different investor classes.

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2.2 Bounding Parameters for Direct Use of Low-T Geothermal Resources

Paul Morgan, Colorado Geological Survey

Presentation discussed permitting and energy needed for direct use. High-level conclusions include:

  • Permitting is generally determined by land/resource ownership.
  • Lindal diagram is a guide to uses based on temperature, but does not indicate required flow (or total energy).
  • Very general guide to energy use:
    • Evaporation (highest flow required)
    • Ice melting
    • Space heating (lowest flow required)
  • If insufficient energy for other uses, consider geothermal heat pumps.

Discussion:

  • Temperature is less important than flow rate -- must have flow for energy to be able to recover sufficient heat.

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2.3 District Heating

John Lund, OIT

Presentation

Presentation provided an overview of the components of a direct use system, and summarized several geothermal district heating systems, including Boise Water District and Ketchum (ID). OIT, Klamath Falls, and Lakeview (OR), Midland (SD), Elko (NV), Canby (CA). High-level conclusions:

  • District heating/cooling provides: space heating and cooling, domestic hot water heating, industrial process heat. The system may be augmented by heat pump to boost temperature, or conventional boiler for peaking.
  • New trends include combined heat and power plants: binary power production and cascaded direct uses using temperatures as low as 98°C (and 74°C at Chena).

Discussion:

  • In district heating systems, fluid is typically re-injected at 40°F. Some systems are taking as much as 60o out, it just depends on reservoir limitations.
  • There is some reservoir decline in direct use systems over time in areas where more heat is drawn out, but this can be regulated. Examples of systems that have been stable for over 50 years.
  • To understand the costs/benefits of a district heating system, you have to included all of the associated electrical requirements (including for pumping).
  • While hot, deep wells drilled for scientific study may not be economic for heat extraction, commercial production of other commodities such as petroleum is.

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2.4 GeoExchange - the "Other" Geothermal

Terry Proffer, Major Geothermal

Presentation

Presentation provided an overview of heat pumps, including a comparison of heat pumps to direct use. High-level conclusions:

  • GHPs can be cost-effective regardless of location, scope and size -- if properly designed and installed, though economy of scale adds value. Simple payback 4 - 8 years.
  • Some GHP installations are problematic or fail because they are installed by inexperienced engineers, contractors, architects and cost-estimating firms. GHPs, while simple in fundamentals, design and installation, do not tolerate assumptions well.
  • New advances in GHP systems include increased thermal and pumping efficiency, streamlined controls, better software, reduced hardware costs and increase in qualified engineers, designers and installers.

Discussion:

  • Buildings are often retrofitted with GHPs - drastically improve efficiency and reduce cost.
  • Many problems that need to be overcome, including:
    • Educating the public and getting data out there on cost savings; We have to learn the language that is needed to earn the traction with the public.
    • Educating contractors (architects and engineers) to ask the right questions and understand the benefits of GHPs.

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Session 3: End Use Innovations

3.1 Integrated Use of Geothermal Energy and Biomass at Cornell

Koenraad Beckers and Maciej Lukawski, Cornell University

Presentation discussed the Cornell Climate Action Plan (CAP) that included lake-source cooling, district heating, and sustainable production of heat and electricity with geothermal (and solar, wind, hydro and biomass). High-level summary:

  • Goal is to reduce GHG emissions from >300k metric tons of CO2e down to 0 by 2050.
  • Investigating several options for achieving goal: (1) co-gen of low-grade geothermal, (2) hybrid geothermal/natural gas/biomass for district heating, (3) hybrid low-grade geothermal/biomass for direct use and co-gen.
  • Source of low-T baseload heat is necessary for transition to a carbon-free campus.
  • EGS becomes competitive at higher natural gas prices even without CO2 credit; provides a buffer from the price volatility of fossil fuels.
  • Cornell campus can be used as a model for many mid-sized communities in the Northeast.
  • Heat cascading and peaking boilers improve the economics of geothermal district heating systems.
  • 10-15% reduction in CO2 emissions with a demonstration project providing 20-25% of campus heat demand from EGS.
  • 0.7-0.8¢/kWhe increase in LCOE
  • LCOH prices comparable to residential natural gas prices (~15$/MMBTU).

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3.2 Desalination

Craig Turchi, NREL

Presentation

Presentation provided an overview of the need for research in desalination technologies, showing that geothermal resources co-exist with brine reservoirs and areas stressed for water. He also provided an overview of the desalination technologies themselves. High-level summary:

  • Desalination can be divided into electrical and thermal (multistage flash; multi-effect distillation). Reverse osmosis (electric) dominates these processes.
  • Typical scenarios don't work for desalination:
    • Geothermal electricity is too inefficient with low-enthalpy heat.
    • Geothermal desalination requires too high of temperature.
  • Other approaches identified:
    • Membrane distillation with heat exchanger
    • Membrane distillation with district heating and use of the geothermal brine
  • Desalination is generally the option of last resort, where there is an alternative:
    • Cost of desalinated water ranges from $0.7/m3to $2/m3
    • Retail water cost in major U.S. cities is $0.6/m3to $5/m3
    • Water for industrial and agricultural users is often highly subsidized
  • Reverse osmosis (all electric) is the leading and lowest cost desalination approach.
  • Opportunities include:
    • Potential to use low-cost geothermal to drive down cost of thermal desalination (energy is 30-50% of the cost of thermal desal methods.
    • Treat RO reject water.
    • Treat highly contaminated water.

Discussion:

  • The worldwide cost of water is $0.005 per gallon, which is on par with retail sale of tap water. For desalination to be used, it's necessary to find the situation where the desalination is the only option for fresh water such as the Gulf of Mexico coast.
  • Petroleum waters can be desalinated for reuse, which can be economic when compared to trucking in fresh water from offsite.
  • Temperature for desalination depends on the technology, but are typically ~100°C, because they like to use steam.
  • Water rights is always an issue, whether it's a direct use or a high temperature system, and particularly to the geothermal resource. Accessing additional water for injection purposes can also be difficult. Desalinated water can supply some of these demands.
  • Geothermal resource rights varies among states. There also may be split estates (land owner is different than mineral (geothermal) owner). Because each situation is unique (land, ownership, depth, temperature, etc.), each project should be researched carefully. The RAPID Toolkit can walk a developer through their project's activities to determine which permits may be needed. (http://en.openei.org/wikiw/RAPID).

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3.3 Building the Future Grid

(Planned topic: Microgrids and Geothermal Direct Use)
Steve Hauser, New West Technologies

Presentation summarized efforts to modernize the electric grid, including the GridWise Alliance, and the Future of the Grid Initiative (DOE Office of Electricity). High-level summary:

  • The grid will no longer be just a delivery pipe -- it will allow two-way power flow.
  • Must be agile and "fractal" -- flexible, adaptable and responsive.
  • Grid will be a mix of regulated and competitive services.
  • Grid is transitioning from a centralized to a less centralized system.
  • Will need to align regulatory process to embrace speed of change and technology innovation.

Discussion:

  • A microgrid is an indigenous solution, using what's available locally to use locally. Combine all resources into one small grid -- campuswide, or military base, more of a minigrid than microgrid, natural gas generator, battery, etc. small grid to provide electricity in a local situation.

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3.4 Industrial Applications

John Lund

Presentation

Presentation summarized industrial uses for geothermal direct use in the U.S.

  • Industrial use is dominated by large facilities (e.g. onion dehydration and heap leaching).
  • Small facilities include: laundries, beer production, mushroom growing, mineral water processing, and industrial park.
  • Total industrial use in U.S.: 38 MWt (140GWh), but was once as high as100 MWt (555 GWh).

Discussion:

  • Direct use heat can be transported about 8 km or 5 miles, though with warmer resources (e.g. Iceland) it can be ship farther (e.g. 25 miles, though lose 20 degrees in the process). In addition to heat losses, it is important to consider the cost of pipe, as well.
  • System security requirements exist, and depend on the facility (e.g. military has a high security).

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3.5 Cascading Uses and Coupling of Technologies

Paul Brophy

Presentation

Presentation provided overview of the mechanics of cascaded use, and then walked through several examples from around the world. High-level summary:

  • Combined heat and power plants improve efficiency and economics of the project and provides energy for direct-use projects (e.g. district heating, greenhouses, spas and pools).
  • Additional job creation is an added benefit to communities.
  • It is important to have good coordination between the operators of the power plant and the direct use systems.

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Session 4: Nontechnical Challenges and Opportunities

4.1 Renewable thermal Energy Policy

The Missing Link to a Robust Market for Geothermal Direct Use
Paul Bony

Presentation

Presentation reviewed the history of greenhouse gas policy, and its bias toward measuring savings in kWh, not in BTUs. High-level summary:

  • Original focus of environmental policy was on reducing kWh of consumption through energy-efficiency programs.
  • Now focus is on ending coal CO2 emissions, but it is being replaced with natural gas, which (according to a report by Cornell) has a larger GHG impact than do coal or oil, particularly for the primary uses of residential and commercial heating.
  • Methane is the silent greenhouse gas -- natural gas is not a clean as coal when you consider purely greenhouse due to leakage in well head, distribution, unburned methane, and transportation.
  • As utilities increase use of variable renewables like wind and solar, the carbon load of a kWh is decreasing, but the carbon load from natural gas use and production is increasing.
  • Carbon offsets from renewable thermal energy can provide an alternative (and lower consumer cost) approach to obtaining carbon reduction goals.
  • Even if/when renewables reach 80% deployment (e.g. REF Study), carbon emissions will not be as low as needed/desired. Until we bring renewable thermal energy into buildings (space and water heating), we will not meet our carbon emission reductions.
  • The UK has launched a Renewable Heat Incentive targeted at driving the increased use of renewables, encouraging further innovation, and bringing down the cost of renewable heating.

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4.2 Direct-Use Profitability: The Economics of Direct Use Geothermal Systems (GEOPHIRES)

Koenraad Beckers

Presentation

Presentation provided an overview of the GEOPHIRES model, and then discussed the economics of three direct-use geothermal systems (as modeled by GEOPHIRES): EGS, geothermal district heating, and geothermal-biomass district heating. High-level summary:

  • GETEM focuses on electricity; GEOPHIRES focuses on direct-use heat.
  • GEOPHIRES is a program to analyze technical and economic performance of geothermal systems for electricity and direct-use heat. It was developed in 2011, and is continually being updated.
  • Using GEOPHIRES:
    • Low-grade geothermal electricity: 20-60¢/kWh
    • Low-grade geothermal direct use: 6-14$/MMBTU

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4.3 Sharing Resources with Geothermal Distributed Energy Systems

(Planned topic: Estimating Impact: Calculating Avoided Generation and Net Negawatts)
Cary Smith

Presentation described details of sharing geothermal resources among multiple buildings (e.g. one for heating, one for cooling) for improved efficiency. This allows for the recovery and use of waste energy from cooling. Presentation also provided two campus examples: Mesa State College and Colorado Mesa University.

Discussion:

  • Approximate cost per ton of installation for the campus project: $500k went into the project, $500k is saved in energy.

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4.4 Business Models - Community Partnerships

Tom Holcomb, Pagosa Waters, LLC

Presentation not available. Summary from student notes:

  • Goals of Pagosa Waters project in Pagosa Verde: Geothermal greenhouse development, Local fresh produce, 24 projects by 2020, CO rural economic development.
  • Creating a business model: identify the problems, opportunities and solutions.
  • For the food industry, sustainability index is determined by organics, water consumed, distance travel, waste, etc.
  • Commercial scale is focused on satisfying needs of the consumer and the market.

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4.5 Community Collaboration in Geothermal Direct Use

Sally High, Pagosa Waters, LLC

Presentation three geothermal direct use projects in Pagosa Springs, CO: Pagosa Verde Greenhouses, Riff Raff Brewing Company, and Geothermal Greenhouse Partnership.

  • Understand the needs/wants/concerns of the locals and cater to those needs: e.g. year-round revenue (greenhouses), locally naturally grown or organic branding, workforce development, economic development, energy savings over fossil fuel, water conservation, community public space (Geothermal Greenhouse Partnership).
  • The most important components of a successful community outreach program include early communication and education. One example is that they hold an annual symposium in Pagosa Springs on geothermal potential and development, Make it a two-way conversation. Will need to repeat your message many times (studies say need to deliver your message 7 times in 7 different ways!). Present information repeatedly as it evolves. Every 6 months, you'll have 30 people say they weren't consulted. Just keep doing it. Community has to come first. Marketing will be a way to passively teach about it.

Discussion:

  • Most greenhouses are currently seasonal because the cost of natural gas is prohibitive. Water conservation is huge in this project.

Closing Discussion

  • Venture capitalists sometimes get a bad rap; if you want money from them, they ask hard questions. Many companies rethink their business plans because of these questions.
  • Clean power plan: clean technology is a high priority for the country, but it varies state to state, particularly how many incentives are going to petroleum versus nuclear, wind, solar, etc. We need to help them understand the complications; worrying about operation, peak electricity, reliability. There has been at least comparison of technology in terms of economics, very rarely there is a comparison of reliability or load factor. This becomes an issue as we increase the contribution.
  • Though geothermal is a clean energy technology, it's not often discussed with other renewables that have clearly defined tax incentives. Society it starting to demand it at the local level, and will grow stronger.
  • Utilities are looking into geothermal development as a way to expand their portfolio.
  • Risk mitigation is needed to attract more investors, e.g. grant, cost-sharing. California has a grant to loan program. If drilling is unsuccessful, money is a grant; if successful, turns into a loan. Interest helps to fund the program and keep it going. Almost all successful geothermal projects have had government or non-developer support. So there is concern from the government perspective: If we give you money to do this, will you be here next year for more?
  • Low gas prices have created geothermal opportunity. There are current rigs that aren't drilling right now because the oil is so low -- opportunity to drill geothermal at lower costs: 15% to drill exploratory holes to see where hot spots might be. Another model is to have drillers as partners rather than contractors; they assume some of the risk, but also some of the reward.
  • Master limited partnerships aren't yet used in geothermal yet, but could be a way to mitigate the risk by pooling the money to work together. The success ratio improves the more drill rigs you drill.
  • We, as an industry need to do a better job of communicating to and educating the public. Kids' textbooks have a geothermal paragraph on Iceland, yet the U.S. has the highest geothermal energy. GRC has materials -- get it into public school curriculums and let's solve that issue around misinformation. That gives you a better advantage, a better project -- getting community invested in it.
  • While there is a great deal of data, individuals perceive that it may not be the right kind of data (necessary for geothermal development), and it is unclear whether DOE funded (exploratory) drilling. DOE funded nearly 100 million of drilling (innovative exploration) where data is required to be uploaded to the DOE Geothermal Data Repository on the Open Energy Information platform located at gdr.openei.org
  • Need to continually think out of the box for game changers that can make geothermal more economically feasible, e.g. adapt directional drilling for reduced surface disturbance.
  • Educating water well drillers so they are not afraid of drilling geothermal wills will help to expand the pool of contractors, keep business local, and reduce costs. We need to address the education at the start.
  • Engage with the international geothermal community, bring the best and brightest, and focus them on a problem. What do we do on these superfund sites? What do we do about coal seam fires? Etc.
  • There is an issue developing geothermal in Colorado because there is a perception that it is "too" regulated or controlled -- this is difficult to overcome. We have an extraordinary opportunity Colorado.

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