It was my honor to attend the European Geothermal Congress (#EGC2022) in Berlin, Germany, in October. I had the opportunity to connect with geothermal experts and industry professionals who have been leading the charge for years and those who are part of the energy transition. What I encountered was a spirit of cooperation and commitment to sustainability.
The time is right and ripe for geothermal energy, an abundant and renewable resource as plentiful as the earth under our feet. It is wonderful to see a commitment from a growing number of countries and companies to subsidize funding to expand R&D, accelerate technologies, infrastructure and access to geothermal energy. I am thrilled to be a part of the global community supporting the energy transition.
Representing Elsevier, a leader in data analytics and academic publishing, I’m honored to collaborate with subject matter experts from academia and industry to develop quality publications in support of sustainability. Our energy team is passionate about the role content can play in accelerating the transition to a more sustainable and carbon-neutral environment. Elsevier’s Journal of Petroleum Science and Engineering is devoting a special issue to technology transfer entitled Geothermal Science and Engineering – Technology Transfer from the Oil and Gas Industry to the Geothermal Industry, which is still accepting submissions.
I asked Elsevier author and journal editor, Dr. Silviu Livescu of The University of Texas at Austin (UT-Austin), along with geothermal expert, visionary and game changer Jay Egg of Egg Geo, LLC, why geothermal is not more widely used in the United States and what it will take for it to be a larger share of the energy mix.
So, why is geothermal not more widely used in the U.S.?
Dr. Sylviu Livescu: There is abundant geothermal energy naturally occurring several miles underneath the surface of the earth. It is effectively inexhaustible, and so renewable, available continuously, and has minimal carbon footprint. Geothermal energy is easily accessible in some locations and is used for electricity generation or for direct use, such as for heating and cooling of residential and commercial buildings, for agriculture or for other purposes [1]. However, the current geothermal energy production represents only approximately two percent of the U.S. renewable energy mix. To scale it up, several critical problems need to be solved, addressing how, where and when to harness it safely, efficiently, predictably and cost effectively.
Although “geothermal energy” is loosely used, it has several different flavors.
First, conventional geothermal systems are naturally occurring hot water or steam flows heated by magma and circulating through permeable rock. They are associated with volcanic systems and limited to regions with active or young volcanoes, such as along the so-called Ring of Fire, and in the U.S. are located mostly in the West.
For instance, in 2021, geothermal energy in California produced 11,116 gigawatt-hours (GWh) of electricity from a total of forty operating geothermal power plants [2]. Combined with another 700 GWh of imported geothermal power, geothermal energy produced 5.72 percent of California’s in-state generation portfolio. Although these systems are well understood technologically, roadblocks are related to the limited area they are available in and long permitting and project development times, typically between seven and 10 years.
Second, geothermal heating and cooling systems, also known as geo-exchangers, ground-source heat pumps or geothermal heat pumps, are systems that exchange heat between the underground and buildings, for both heating and cooling. These systems can be used almost anywhere in the U.S. because all areas have nearly constant shallow ground temperatures, although systems in various locations have varying degrees of efficiency and cost savings.
The world’s first district heating system was built 1892 in Boise, Idaho, to serve 200 homes and 40 downtown businesses. Today, there are four district heating systems in Boise that provide heat to over five million square feet of residential, business and governmental space. There are now 23 district heating systems in the U.S. and dozens more around the world [30]. The U.S. geothermal heating and cooling market is so immense, that it would require more than one hundred billion feet in drilling borehole footage, if all the existing buildings were retrofitted to use geothermal energy for their heating and cooling needs.
For context, the total completed lateral footage of wells in the Permian, the most prolific oil and gas field in the U.S., is expected to reach a record high of 50 million feet this year. While there are many engineering firms and drilling contractors installing geothermal and heating cooling systems in the U.S., the main roadblocks for higher adoption of geothermal heating and cooling systems are related to complex projects requiring effective collaboration between multiple technical domains and industries, a fragmented market that lacks innovation and research and development funding, and simple technologies used today driven by low-operating costs.
Third, enhanced and advanced geothermal systems for power generation from geothermal energy anywhere outside of the Ring of Fire area have started to gain significant momentum. These are systems that do not have the natural combination of heat, fluid and permeability, like conventional geothermal systems, and need to emulate them. For instance, the Department of Energy’s flagship project, Utah FORGE, is pushing the research envelope for understanding how enhanced geothermal systems can be constructed using existing oil and gas technologies.
[In September], U.S. Secretary Jennifer M. Granholm announced the U.S. Department of Energy’s fourth Energy Earthshot™, seeking to cut the cost of enhanced geothermal systems by 90 percent by 2035. While several startups are looking to prove various technologies for constructing these geothermal systems requiring drilling in deeper, hotter and tougher environments than those from oil and gas, significant advancements and innovations in technologies, business models, and regulatory and policy affairs are needed and expected in the next decade. For this, much more funding for research, technology development and deployment is critically required.
Fourth, there are many research topics budding in the emerging “geothermal anywhere” industry. Among them, the most popular are repurposing oil and gas wells to produce geothermal energy, co-production of geothermal energy and rare metals such as lithium, using subsurface wells and pore space for thermal storage, using geothermal energy coupled with direct air-capture technologies and so on. All of these topics, despite enormous potential, require significant technology development and innovations.
Jay Egg: I appreciate Sylviu’s comments and will add my thoughts as to why geothermal is not more widely used in the United States.
Firstly, unlike wind and solar power systems, low-temperature geothermal exchange systems for buildings are not visible; they are out of sight and out of mind. That takes away from the “green badge of honor” that distinguishes renewable energy buildings and communities with massive wind power generators, and impressive solar electric collecting arrays. There is just nothing to see with a geothermal heating and cooling system once it’s installed.
Additionally, putting in a geothermal exchanger involves any one of about six major methods: boreholes, trenches, surface water, infrastructure, wastewater, and other types of exchange. The difference in cost varies widely but it is nonetheless an infrastructure cost that adds to the initial installation cost of the system. A good analogy is to talk about the cost of installing a sink in a home that does not have access to running water or sewer. That $100 sink, to make it operable, will need a $20,000 water well installed along with a $25,000 septic tank system. The same principle holds true with a geothermal heating and cooling system. The home air conditioning system costs about the same as any home heating and cooling system. But to install it, we need the infrastructure. However, the infrastructure is a one-time cost that will continue to serve the property for generations to come.
What will it take for geothermal to be a larger share of the energy mix?
Sylviu Livescu: One thing that might get more people talking about geothermal energy is the serendipitous opportunity it offers to the oil and gas industry, which is infamous for their oversupply, persistently low prices, and cratering demand caused by the pandemic. Consequently, it has been losing jobs, even if now all oil and gas companies are remarkably busy. In addition to all of the U.S. national laboratories and many universities with long or recent traditions in geoenergy research, many companies from the oil and gas industry and non-profit organizations, such as the Society of Petroleum Engineers (the largest organization for oil and gas professionals), have started to join the “geothermal anywhere” momentum, giving hope that power generation and direct heat applications using geothermal energy could be within our reach.
Jay Egg: I was asked the same question circa 1990 after finishing my first thermal energy network for a mixed-use community in Florida. This apartment complex was the subject of a Tampa Bay morning show, and the anchor was on site live during the broadcast. Of course, we were there with him, and every time they cut back to our field report, we would be looking at another part of the system, from ground loops, to heat pumps, to thermostats, and finally an interview at the end of the segment.
The last question the anchor asked me was, “When will geothermal be available to all people in the United States?” I responded that when geothermal systems become part of a utility network, like city water, city sewer, electric and communications, then everybody would be able to hook up. He went on to ask when I thought that would take place. I told him that while I had no way of knowing, I hoped that it would be in my lifetime. I’m pleased to say that we are on the cusp of just such a revolution with the passage of the Thermal Energy Networks and Jobs Act of 2022 in New York, which was signed into law by Governor Hochul on July 5, 2022.
Fran Kennedy-Ellis: Sylviu and Jay summarized it well: It’s an exciting time to be working in energy. Geothermal energy is at the core of this country’s transition to more sustainable energy solutions.
Disclaimer: The views and opinions expressed herein are those of the authors and do not necessarily reflect the official policy or position of Elsevier.
Bibliography
1. U.S. Department of Energy Geothermal Technologies Office 2017. GeoVision: Harnessing the Heat Beneath our Feet. https://www.energy.gov/sites/default/files/2019/06/f63/GeoVision-full-report-opt.pdf.
2. California Energy Commission 2022. California Geothermal Energy Statistics and Data. https://ww2.energy.ca.gov/almanac/renewables_data/geothermal/index_cms.php.
3. National Renewable Energy Laboratory 2021. U.S. Geothermal Power and District Heating Market Report. https://www.nrel.gov/docs/fy21osti/78291.pdf.
4. Geothermal Rising, 2022. New York Approves Landmark Thermal Network Legislation. https://www.geothermal.org/our-impact/blog/new-york-approves-landmark-thermal-network-legislation
For further reading:
Geothermics, an international journal devoted to the research and development of geothermal energy. https://www.sciencedirect.com/journal/geothermics
Geothermal Energy Systems, Dincer, I. and Ozturk, M. Elsevier, 2021. https://www.elsevier.com/books/geothermal-energy-systems/dincer/978-0-12-820775-8
Geothermal Power Generation, DiPippo, Elsevier, 2016. https://www.elsevier.com/books/geothermal-power-generation/dipippo/978-0-08-100337-4
Reskilling of energy pros can tap geothermal’s vast potential, Elsevier Connect, 2022. https://www.elsevier.com/connect/reskilling-of-energy-pros-can-tap-geothermals-vast-potential
Headline photo courtesy of Utah FORGE, Eric Larson.
Fran Kennedy-Ellis, senior acquisitions editor, Elsevier – Geothermal Energy, Thermal Engineering, and Oil & Gas in Transition. Prior to joining Elsevier, Kennedy-Ellis’ publishing experience includes serving the Society of Petroleum Engineers (SPE), University of Texas’s Petroleum Extension Service (PETEX), International Association of Drilling Contractors (IADC) and Texas Tech University Press.
Dr. Silviu Livescu, professor, University of Texas at Austin, SPE technical director for data science and engineering analytics, and incoming editor-in-chief, Elsevier Geoenergy Science and Engineering.
Jay Egg’s 35 years in the geothermal industry have brought him the labels of Visionary and Game-changer in the adoption and deployment of thermal energy exchange. As a global geothermal expert, Egg focuses on feasibility and design for thermal energy networks and supporting activities involving geothermal exchange implementation, aquifer related feasibility and special permitting such as utility-scale geothermal exchange systems. Egg is a Certified Geothermal Designer, mechanical professional, co-recipient of the 2020 Constellation Prize for Policy Change, and passionate thermal energy advocate who started his career in nuclear power with the U.S. Navy.
