An introduction to the next clean energy frontier: Superhot rock geothermal and pathways to commercial liftoff
This blog is part of a series exploring and explaining the science behind next-generation geothermal energy, with a special focus on superhot rock geothermal, through a curated tour of influential technical and academic papers. It highlights key features of the United States Department of Energy’s report, Pathways to Commercial Liftoff: Next-Generation Geothermal Power.
Today’s geothermal systems have long provided such a small portion of the world’s electricity generation that analyses of the global energy mix tend to lump the technology into their “other sources” category. However, as highlighted in the U.S. DOE’s recent report, Pathways to Commercial Liftoff: Next-Generation Geothermal Power (Liftoff Report), this may soon change, thanks to substantial advancements in enhanced geothermal systems (EGS) development, a type of next-generation geothermal, as showcased at the U.S. Department of Energy’s (DOE’s) Utah Frontier Observatory for Research in Geothermal Energy (FORGE) and Fervo Energy sites.
These advancements in next-generation geothermal systems provide a direct benefit to making superhot rock geothermal (SHR), a form of next-generation geothermal technology capable of tapping subsurface temperatures exceeding 400 °C, a reality – and drawing invaluable support from governments around the world. The U.S. DOE allotted funding last year through the Geothermal Technologies Office (GTO) for a SHR EGS demonstration at Newberry Volcano in Oregon and this year through Advanced Research Projects Agency – Energy (ARPA-E) with a new program that will dedicate $30 million to focus on the development of SHR resources. Additionally, the government of New Zealand recently announced that it will allocate up to $60 million for research on SHR technology, and the European Union (EU) Member States, as well as the European Parliament, called for a dedicated action plan late last year to accelerate deployment of geothermal energy and new innovative strategies.
Given the growing public-sector interest in next-generation geothermal development, it’s helpful to review the U.S. DOE’s 2024 Liftoff Report, to better understand the technology’s value proposition, and its pathway to commercialization. This report is still considered to be a flagship report on next-generation geothermal. The report includes input from industry and other geothermal experts outside of the government and incorporates the most up-to-date research into the challenges and opportunities to advance the commercialization of next-generation geothermal technologies.
Next-generation geothermal could power the U.S. for thousands of years
The world is going to need more energy, not less. According to the Liftoff Report, electricity demand growth projections have increased, requiring strategies that limit emissions while meeting this additional demand. Geothermal (both conventional and next-generation) is one of the few sources of energy that can provide reliable electricity around the clock with little to no emissions. Because conventional geothermal resources are limited to areas where shallow heat, water, and fluid pathways are available, geothermal energy currently provides only 0.4% of total installed global power. In the U.S., 40% of conventional geothermal capacity is sourced from a just single geothermal field: The Geysers in California. Many times, this scarce resource is made further inaccessible due to its remote and concentrated location, limiting its ability to scale and contribute more broadly to the energy mix.
Because there is no unique geologic constraint for next-generation geothermal resources, the technology could be deployed anywhere around the globe, allowing its power generating potential to be much larger than that of conventional geothermal resources. According to the Liftoff Report, there are approximately 0.4 terawatts (TW) of potential conventional geothermal resources in the U.S. However, the potential is nearly 14x greater (5.5 TW) for next-generation geothermal. 5.5 TW of generating capacity would provide over 10x the electricity consumed by the U.S. in 2022 – creating an energy source that could power the U.S. for thousands of years.
Next-generation geothermal is within reach
Next-generation geothermal technologies have been an active area of research, development, and demonstration (RD&D) for over 50 years. Research on enhanced geothermal systems (EGS) began in the early 1970s with the DOE’s Fenton Hill project in Los Alamos, New Mexico, and there have been dozens of EGS projects deployed around the world since. Recent successes in EGS development have included the successful stimulation and circulation tests at the Utah FORGE site and the significant cost reductions from Fervo Energy’s drilling operations. Closed-loop geothermal systems (CLGS) have also been a focus of research and development for nearly half a century. More recently, Eavor is expecting to generate geothermal power in Germany using their closed-loop technology this year. With progress being made in EGS and CLGS technologies, the Liftoff Report suggests that commercial liftoff of next-generation geothermal technology is attainable as early as 2030.
Expansion of next-generation geothermal could also provide permanent local job opportunities to experts in the oil and gas and electric power industries. Geothermal power creates 3-4 times as many long-term jobs per megawatt as solar and wind, and the workforce with transferrable skills needed to develop and operate a mature geothermal industry already exists.
The cost of next-generation geothermal deployment is already decreasing
Large upfront costs associated with drilling have been an important hurdle to deploying new next-generation geothermal projects. However, the cost of drilling has already decreased substantially thanks to cost declines from iterative improvements (also known as the “learning rate”). As part of these iterative improvements, data from the U.S. DOE FORGE site and private sector deployment have shown significant increases in drilling rates, which relates directly to decreases in upfront project costs. As is shown in Figure 2, drilling rates at the FORGE site have improved by over 500% since the first well was drilled in 2017. Fervo has reported a 300% increase in drilling rates, resulting in a cost decrease of nearly $5 million across 6 wells in 6 months.
Based on the rapid cost reductions that have already been demonstrated by today’s next-generation geothermal projects, the National Renewable Energy Lab (NREL) recently updated the estimated drilling costs from the DOE’s 2019 GeoVision analysis for vertical and horizontal wells by up to 24% and 26% respectively. Based on the recent cost improvements, the Liftoff Report projects that the cost of next-generation geothermal projects will fall below the cost of other baseload power sources such as nuclear and natural gas with carbon capture and sequestration by 2035.
More demonstration projects and funding are needed to achieve geothermal everywhere
The last few years have shown an increased interest in funding next-generation geothermal projects, with over $600 million in capital raised between 2021 and 2024 in EGS and CLGS projects (Figure 3). Early financing is a key step to commercially deploying next-generation geothermal projects due to their high up-front costs. Additionally, next-generation geothermal is unique in that the resource is better understood as new projects are developed, due to the resource being located belowground. The Liftoff Report highlights additional needs to rapidly commercialize next-generation geothermal projects, including:
- Demonstration projects in at least five separate geologic settings to reduce risk and verify resource availability;
- An additional $225-250 billion in investment that is driven by a new ecosystem of developers, investors, utilities, and other offtakers that leverage existing workforces and supply chains;
- Further RD&D and iteration to drive down deployment costs, similar to those observed in the unconventional shale oil & gas industry;
- Reducing permitting timelines for geothermal projects on public lands; and
- Transparency of operational data to overcome the challenges of advancing a new technology that utilizes a belowground resource.
What’s next?
As a form of next-generation geothermal at high temperatures, SHR builds on the successes of today’s lower temperature projects by maximizing the energy output from even higher temperature formations. The growing number of recent accomplishments makes this especially exciting and demonstrates that we should not stop at temperatures currently limited by the upper bounds of subsurface tools, which were created for the oil and gas industry. Instead, technology development should drive innovations towards tools and materials that are fit-for-purpose at higher temperatures. According to the recent Future of Geothermal Energy report by the International Energy Agency, next-generation geothermal could deliver up to 15% of the total global electricity generation growth to 2050 in addition to the 1% that is currently met by conventional geothermal.
As highlighted in the Liftoff Report, a mature next-generation geothermal industry could power the entire U.S. given our current energy demands – with room to grow. Fully unlocking SHR’s potential – capable of generating 5-10 times the MW output of a typical commercial geothermal well – could power the U.S. ten times over, all while requiring fewer wells. The potential is immense, and progress is already underway to make SHR a reality through advancements in current next-generation geothermal projects.
Stay tuned for more from CATF as we push forward with bold research and initiatives to strengthen the next-generation geothermal industry and scale SHR to realize the full potential of the heat beneath our feet.
This blog is part of a series exploring and explaining the science behind next-generation geothermal energy, with a special focus on superhot rock geothermal. You can read the first blog in the series here. Through a curated tour of influential technical and academic papers, the series aims to provide a fresh perspective from a geoscientist entering the geothermal industry. The goal is to share my learning journey and encourage collaboration around these groundbreaking solutions, which are critical to achieving a clean energy future. Whether you’re new to geothermal or looking to deepen your knowledge, I hope this series offers valuable insights into this fast-evolving field.
