Published on 07/03/2024
Sonoma Clean Power, in partnership with the counties of Sonoma and Mendocino, is leading an effort to build 600 megawatts (MW) of new geothermal energy in our service area over the next decade.
The goal of this initiative, known as the Geothermal Opportunity Zone or “GeoZone”, is to secure a long-term supply of affordable, reliable clean energy for our customers, while helping to fight the global climate crisis.
Here are some of the GeoZone’s highlights:
In 2018, California passed Senate Bill 100, establishing an ambitious goal of achieving 100% clean electricity by 2045. In the next 20 years, the majority of our buildings, homes, transportation, and industries are expected to be powered by clean energy sources such as solar, wind, and geothermal.
Currently, our state does not have enough clean power to turn this goal into a reality. And despite rapid growth in renewable energy, California has not been able to retire its dirtiest natural gas power plants due to a lack of clean energy at times when solar and wind are not producing and batteries are depleted-including stretches of nighttime and dark winter days.
To achieve 100% renewable and zero-carbon electricity by 2045, California must secure a diverse set of energy resources to provide the reliability and flexibility our state desperately needs. Sonoma Clean Power’s role is to help our region achieve this target as quickly and affordably as possible.
Because geothermal power can generate clean energy 24/7, it has significant potential to replace natural gas as a reliability resource on a large scale.
If the GeoZone is a success, Sonoma Clean Power can provide 100% clean energy to our customers around-the-clock and cut all ties to natural gas plants.
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Sonoma Clean Power procures energy from a mix of clean sources, including a considerable amount of geothermal power from the world-class geothermal resource in our backyard, the Geysers.
To stay on track with our ambitious climate goals, Sonoma Clean Power expects that roughly 40% of our energy will need to come from geothermal resources by 2038.
California regulators have also identified a need for significant growth in this sector, pointing out the need to more than double the state's existing geothermal capacity by 2035 in their latest portfolio for transmission planning.
Over the last decade, there has been minimal growth in geothermal capacity in the state. The scarcity of naturally occurring rock fractures and the uncertainty of a long-term water supply has limited the growth of conventional geothermal production.
In addition, all existing geothermal resources at the Geysers are contracted for, meaning Sonoma Clean Power cannot purchase more energy from their facilities at this time.
Recent breakthroughs in “next-generation geothermal technologies” are enabling geothermal development in areas beyond those suitable for conventional geothermal.
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Unlike conventional methods, natural rock fractures and a constant supply of water are not required for next-generation geothermal, allowing new facilities to be sited in far more places. Other benefits include relatively small-scale surface equipment and minimal site disturbance.
Sonoma and Mendocino counties’ existing geothermal field make it an ideal region to test and incubate these emerging technologies.
In 2022, the GeoZone effort kicked off with Sonoma Clean Power issuing a Request for Information to identify companies interested in a public-private partnership to accelerate the development of geothermal resources in our service area.
After a comprehensive evaluation process, which included review by industry experts, a local permitting agency, and public stakeholders, staff recommended three finalists with successful development experience and technologies that met Sonoma Clean Power’s selection criteria, including:
SCP’s three development partners are Eavor Inc., Chevron New Energies, and Cyrq Energy. Every partner has proposed different next-generation geothermal technologies to test and explore within the GeoZone, each with their own advantages.
The GeoZone partners are expected to develop pilot projects of up to 20 MW showcasing the feasibility of their technologies. If successful, the plan is for each partner to scale up their project up to 200 MW or more.
SCP will be given the right of first refusal for the geothermal power generated by these new resources, and the excess clean energy will be available to other power providers throughout California to purchase.
Currently, the GeoZone partners are working to identify potential sites for their pilot projects. Each project will go through its own environmental impact review process with extensive opportunities for public input.
Additionally, the pilot projects and any subsequent development are required to adhere to the objectives SCP has established for environmental protection, including minimization of impacts to land, air, water, and seismicity.
Sonoma Clean Power encourages early and frequent public engagement with our GeoZone effort. Through community presentations, town halls, public meetings, and more, we hope to provide a variety of opportunities for the community to share concerns, ask questions, and establish preferences that can steer the design of new, local geothermal development.
While our partners will lead on communicating any project-specific details, Sonoma Clean Power will continue to facilitate public engagement as project locations and technologies are identified.
Visit our GeoZone webpage to learn more, and please contact us with questions or comments. You may also request to be added to our GeoZone email updates list.
Geothermal technology can provide clean power 24 hours per day, 365 days per year. These are exactly the kind of clean and firm energy resources that California desperately needs to eliminate the use of natural gas and reduce dependence on other fossil fuels.
The GeoZone initiative will give us the ability to improve energy independence and reliability in the region, while protecting our environment, eliminating the export of our pollution, providing long-term cost savings to customers, creating jobs, and demonstrating the scalability of this technology statewide and beyond.