In this five-part “Geothermal Mythbusters” series, Fervo will debunk common misconceptions associated with the geothermal industry.
Fervo prides itself on applying innovative drilling techniques from the oil and gas industry to geothermal. Given the similarities between our work and unconventional oil and gas, we are often asked whether geothermal production poses the same environmental risks to frontline communities as fossil fuel extraction.
The short answer is no. As a carbon-free resource, next-generation geothermal development can provide economic opportunities to local communities without the associated air pollution and greenhouse gas emissions typical of oil and gas development. Fervo highly values environmental health and safety and has instituted controls across our projects not only to protect local communities but to lift them up and involve them.
Prioritizing Environmental Health and Safety
Geothermal energy faces three common misconceptions about its effects on communities and the environment: steam from facilities can obstruct the views of nearby residents, stimulation fluids can contaminate subsurface rocks and aquifers, and subsurface stimulation can cause induced seismicity. Fervo combats all three of these issues using state-of-the-art geothermal technology that minimizes environmental impacts.
First, by relying on binary cycle power plants to generate electricity, Fervo does not emit steam during facility operations. Geothermal developers have historically used flash plants to convert geothermal reservoir fluid to steam to power turbines. In a flash plant, hot water under high pressure travels up a production well to a low-pressure tank on the surface, which “flashes” the water into vapor. Vapor that is not cooled and reinjected underground is released into the atmosphere, generating steam and some greenhouse gas emissions.
In a binary cycle power plant, hot geothermal reservoir fluid passes through a heat exchanger, vaporizes a separate working fluid with a relatively low specific heat, and is then reinjected underground. The vaporized working fluid powers a turbine; the geothermal fluid never actually comes into contact with the turbine. This power plant design eliminates the release of steam and carbon emissions.
Second, because they use simplified stimulation fluids than oil and gas, Fervo’s projects — and geothermal operations more broadly — are much less likely to contaminate the local environment. Oil and gas stimulation requires a greater number of chemicals to stabilize hydrocarbon-bearing reservoirs. Because geothermal stimulation pumps water and sand into reservoirs where no hydrocarbon is present, stimulation fluids can be much less complex and much safer for the environment.
Finally, Fervo reduces seismic risks by partnering with the US Geological Survey to monitor seismic activity in real time. We have built a detailed induced seismicity mitigation plan and stoplight system to curtail operations if seismicity exceeds a certain magnitude. To date, none of our operations have caused seismicity significant enough to trigger the stoplight protocol. These results show that induced seismicity from geothermal can be mitigated through planning operations around seismically active zones and proactive monitoring during operations.
Actively Supporting Frontline Communities
Next-generation geothermal not only preserves the environmental health and safety of local stakeholders; it provides frontline oil and gas communities with accessible green jobs.
If you visit Fervo’s commercial project in northern Nevada, you will notice logos of oilfield services companies. H&P, Liberty Energy, Schlumberger, and many other oil and gas contractors have helped Fervo successfully drill the first two horizontal geothermal wells in history.
The compatibility between oil and gas and geothermal allows fossil fuel workers to transition seamlessly to next-generation geothermal development. For families typically subject to the boom and bust cycles of the oil and gas industry, work in geothermal can provide welcome stability.
Fervo’s approach to next-generation geothermal embraces the just transition holistically. We ensure that our operations safeguard the local environment, limiting steam, hazardous chemicals, and seismic activity. We also strive to employ workers from communities most affected by the pivot to clean energy, embracing the expertise of the oil and gas industry.
