As discussed in the introduction to The Opportunities for Geothermal Energy, each of GTO’s subprograms focuses on a distinct aspect of geothermal energy and addresses challenges unique to those aspects. Several additional GTO activities, however, cut across multiple subprograms. Many of GTO’s cross-cutting^[7] activities are discussed in this MYPP within the Research Area to which they apply—e.g., Subsurface Enhancement and Sustainability covers all Subsurface Accessibility research, whether it applies to geothermal electricity or GHPs. By contrast, this section highlights technology-agnostic activities GTO is undertaking to research specific opportunities that impact all GTO Research Areas.

[7] Note that, in Section 2.1.3.4, “cross-cutting” refers to activities that have some combination of science and exploration techniques but apply to Exploration and Characterization specifically.

Machine Learning

Machine learning techniques offer substantial opportunities to advance technologies while also reducing costs across all geothermal resource types and operational lifecycle stages. GTO funds a portfolio of projects that is harnessing a range of supervised and unsupervised machine learning approaches to improve and optimize geothermal exploration, resource characterization, drilling target identification, drilling practices, induced seismicity risk reductions, and operational efficiency improvements of geothermal power plants and associated well fields.

The value that machine learning can provide is linked directly to the quality of datasets available for input and analysis. GTO’s existing machine learning research portfolio leverages a unique opportunity through collaboration with domestic and international commercial geothermal operators who are providing commercial drilling and field development datasets for research. Another substantial opportunity exists over the next five years given the number of field-based initiatives that are ongoing or will be developed (e.g., FORGE, exploration of hidden systems in the Great Basin). This confluence of step-changes in data-processing sophistication along with direct access to DOE-funded field datasets across a range of geothermal resources underscores the unique opportunity to continue driving formerly empirical observations and correlations toward predictive reservoir characterization and behavior.

In addition to potentially supporting field-scale activities over the next five years, machine learning techniques may have possible benefits for optimizing design and operational efficiencies of low-temperature geothermal resources (e.g., predictive behavior adaptation by GHP systems). Machine learning may also contribute to other areas that are of strategic interest but suffer from data sparseness, e.g., geothermal resource assessments. GTO’s machine learning activities include collaboration with relevant stakeholders, including federal partners. Using machine learning to characterize and correlate key geothermal resource parameters, e.g., temperature and ground thermal conductivity, can reduce geothermal resource uncertainty—and, in turn, lower exploration risks and improve resource identification.

Advanced Manufacturing

Geothermal environments can pose manufacturing challenges for creating tools and components because they necessitate materials that can withstand variable subsurface stresses resulting from high temperatures, thermal cycling, and rock strengths, as well as corrosive working fluids. As such, manufacturing with high-grade materials and specialized geometries can be necessary. However, the combined effects of low production volumes required to supply the existing U.S. geothermal market and the diminished lifetime of these tools due to the harsh conditions encountered in geothermal environments result in prohibitively high manufacturing costs.

As a traditional GTO research pillar, geothermal tool RD&D has realized game-changing advancements across the application space for geothermal, such as the PDC bit (Gallaher et al. 2010). GTO efforts include a prize competition in collaboration with the DOE Advanced Manufacturing Office to integrate additive manufacturing approaches that can improve the design and performance of geothermal tools, components, and equipment. Additionally, novel coatings for downhole equipment and synthesis of new well-construction materials are all actively represented in the GTO research portfolio. Opportunity exists to continue leveraging these efforts as well as broader DOE investments in advanced manufacturing that are benefitting industries with shared challenges (e.g., oil and gas, clean energy, aerospace, automotive) to accelerate technology development and innovation across all geothermal energy resource types. Such research advancements also represent technology transfer opportunities with other subsurface energy applications, including oil and gas.

Technology Commercialization

GTO’s primary mission is reducing the risk and costs associated with developing geothermal resources. Work is conducted in collaboration with a robust network of companies, entrepreneurs, academic researchers, and other vital stakeholders. These stakeholders represent the natural hand-off between programmatic basic research and broader commercial adoption of geothermal technologies. GTO actively supports commercialization efforts for both DOE-developed and industry-developed technologies through several financial mechanisms, including DOE’s Small Business Innovation Research and Small Business Technology Transfer programs and DOE Technology Commercialization Fund awards. GTO supports geothermal-focused entrepreneurs through programs such as the Lab-Embedded Entrepreneurship Program. Where applicable, GTO also supports and funds demonstration activities. By testing and proving technology advances in the field, GTO-funded researchers can help provide real-world data and experience, thus reducing risk for geothermal developers to adopt enhancements or new technologies. GTO’s collaborative work and demonstration help move technology commercialization forward across all geothermal applications and are crucial to the ultimate growth of geothermal energy.

Energy Transitions

Increasing coordination with the oil and gas sector can lead to important opportunities as the geothermal community focuses on integrating with the sector’s infrastructure, workforce, and the unique skillsets. GTO and the broader geothermal community understand that this integration will not only accelerate geothermal deployment but will also encourage this sector’s just transition into a renewable energy future.

According to the U.S. Energy Information Administration, there are nearly 1 million active oil and gas wells in the United States plus a vast number that are presently idle but not yet plugged and abandoned (U.S. Energy Information Administration 2020). Many of these wells access temperatures that can supply geothermal energy, including the co-production of low-enthalpy electricity generation and direct-use applications alongside oil and gas extraction. Utilization of idle wells for geothermal power or heat can eliminate their substantial methane emissions. Existing wells (in particular, abandoned or idle wells) and associated infrastructure also represent a significant capital investment that could be leveraged for development of geothermal resources. These assets could also be applied to thermal energy storage where development costs may be prohibitively high.

In addition to infrastructure, the oil and gas industry also has a large and highly skilled workforce—the skills and knowledge of which are applicable and transferable to the geothermal sector. Integrating the oil and gas workforce and their skills and knowledge into the geothermal community will result in highly trained oil and gas workers ready to focus on geothermal research, development, and operations. The replicability and reliability of oil and gas practices, employed at geothermal projects, can dramatically impact the economics of geothermal energy use and accelerate development of geothermal energy resources. Most importantly, oil and gas workers will benefit from secure and consistent job opportunities; the geothermal industry could offer as many as 250,000 jobs annually and $219 billion of cumulative economic impact annually by 2050 (Millstein et al. 2019).

Fluctuating economic conditions in the oil and gas industry and increased acceleration toward a clean energy economy open possible collaboration between the geothermal and oil and gas industries that can benefit both sectors and the nation. Engaging with the oil and gas industry and finding shared opportunities will be an important focus across GTO’s research portfolio in the next five years.

Stakeholder Engagement, Communication, Education, and Outreach

Stakeholder engagement will be critical to fostering geothermal deployment. GTO’s fundamental engagement goal is to develop relationships with and listen to individuals and communities, ascertain their goals and challenges, and empower them to explore how geothermal can impact their lives. Along the way, thorough and strategic communication and engagement activities can focus on the benefits and uses of geothermal energy as well as strategic socialization of the numerous opportunities offered by DOE and other entities for deploying geothermal via technical assistance, technology, and system development and deployment.

Geothermal energy is a renewable energy supplying benefits and advantages commensurate with those of solar, wind, water, bioenergy, and other renewable sources. Geothermal is also ubiquitous and diverse in presentation—on display in Yellowstone National Park; providing significant, firm, flexible clean energy generation for states including Nevada, California, and Hawaii; and harnessed in homes across the country with GHPs. Geothermal resources can provide clean energy throughout the nation and for a range of consumers—from small rural communities that need distributed power to urban centers with high energy demands and large populations. The national laboratories contain a deep bench of geothermal specialists, economists, and champions, and the GTO budget has grown steadily over the past decade to $110 million in FY 2021 appropriations. There are currently 2.6 GW of geothermal electricity production online in the United States that could reach 60 GW by 2050 with the right technology advancements. Also by 2050, 17,500 GDH systems and 28 million GHPs could be deployed nationwide.

Nevertheless, geothermal energy suffers from a broad lack of awareness. The geothermal community, along with GTO, assumes that this is due to geothermal energy’s unique features, such as its subsurface nature and lack of surface manifestations, current geographic limitations, and low-profile infrastructure. Amongst stakeholders that are aware of geothermal energy, questions of geothermal’s economic and technical feasibility, perceived risk of induced seismicity, volcanic hazards, and water use and contamination permeate.

To move beyond this paradigm, GTO and the geothermal community will work with communities and stakeholders to better understand how geothermal energy and infrastructure can provide meaningful community benefits and support both communities and the geothermal industry to develop best practices and projects that realize those benefits. Engagement activities include roundtables, interviews, and conversations with a representative array of current and potential geothermal stakeholders. The subsequent engagement and outreach campaign will likely include website and collateral development, partnerships with local and state nonprofits, and high impact relationship building for geothermal message procreation and a disperse advocacy network.

GTO will also continue to weave the priorities of energy equity, environmental justice, state and local collaboration, workforce development, and diversity in STEM throughout the programmatic portfolio and engagement and communication activities. Additionally, GTO will collaborate with other EERE and DOE technology offices on new Joint Office Partnerships, buttressing and supporting that work through innovative means within the Office.