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Harnessing the Earth's warmth in Sonoma County

A new venture into clean energy

Sonoma County is embarking on an ambitious project with Chevron New Energies to explore the potential of Enhanced Geothermal Systems (EGS). Supported by significant investment from the Department of Energy, this initiative aims to revolutionize how we produce clean energy and phase out natural gas from Sonoma Clean Power's energy sources.

Overcoming regulatory hurdles

In pursuit of this goal, March will see efforts to secure essential drilling permits. With CalGEM under pressure from a heavy workload and legal complexities, Sonoma Clean Power is adopting a dual strategy. They're working with Sonoma County to revise local planning regulations for better control over energy projects and advocating for legislation to streamline the permitting process.

Expanding geothermal energy sources

The project seeks to more efficiently tap into the Earth's natural heat, building on Sonoma County's history with geothermal energy from The Geysers. By using EGS technology to access and create geothermal resources, this initiative could provide a sustainable and reliable power source in previously unsuitable areas.

The GeoZone project

In collaboration with Chevron New Energies, the GeoZone project aims to develop 600 MW of local geothermal capacity. This effort is supported by the DOE and aims to meet clean energy targets and reduce fossil fuel reliance.

Learning from Utah's FORGE initiative

A similar project, the FORGE initiative in Utah, showcases the potential of EGS technology. This collaboration between the Energy & Geysers Institute at the University of Utah and the U.S. Department of Energy is pioneering ways to harness geothermal energy in new locations, offering insights into creating a sustainable energy future.

Enhanced Geothermal Systems (EGS) represent a significant advancement in the field of renewable energy, particularly in how we harness the Earth's natural heat. Unlike traditional geothermal power, which relies on natural steam sources or hot water reservoirs, EGS technology creates these conditions artificially, making it feasible to generate geothermal energy in locations previously considered unsuitable.

How EGS Works:

The process begins with drilling deep into the Earth's crust to reach the hot rock below. Then, water is injected into this hot rock under high pressure, which causes fractures to open. As the water seeps through these fractures, it heats up and is pumped back to the surface as steam. This steam can then be used to drive turbines, generating electricity.

What’s different about this approach?

The key difference lies in the ability of EGS to create geothermal resources where none existed before. Traditional geothermal systems need natural geysers, hot springs, or volcanic activity to produce steam. In contrast, EGS can be implemented in a broader range of geographical locations because it does not rely on naturally occurring steam or hot water reservoirs. Instead, it utilizes the ubiquitous heat found beneath the Earth's surface, effectively turning the planet's crust into a potential power source anywhere drilling is possible.

This technology's promise lies in its potential to significantly expand the use of geothermal energy, providing a stable, reliable, and clean power source. While traditional geothermal energy has been limited to certain geographical areas, EGS could enable many more regions around the world to tap into geothermal power. This could play a crucial role in transitioning to renewable energy sources, reducing greenhouse gas emissions, and fighting climate change.

The development and deployment of EGS, as demonstrated by projects like FORGE in Utah and the initiative in Sonoma County, mark an exciting evolution in renewable energy technology. By overcoming the limitations of traditional geothermal systems, EGS opens up new possibilities for sustainable energy production on a global scale.

Addressing concerns and capacity

Despite some concerns over Chevron's involvement, the project was approved, recognizing the company's drilling expertise. The GeoZone geothermal power plant, with a capacity of 20 MW, highlights the project's potential to significantly contribute to the local clean energy supply.

Community engagement

Sonoma Clean Power's Community Advisory Committee encourages public participation in their monthly meetings. Available both in-person and online, these meetings offer the community a chance to contribute to Sonoma's clean energy future, with schedules and agendas accessible to all interested parties.

The meeting schedule and the agendas for upcoming meetings are available here.

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