George Santayana and the Coming Push for Advanced Geothermal Energy
George Santayana, the Spanish-American philosopher and poet, famously wrote, “Those who cannot remember the past are condemned to repeat it.”
That admonition applies to the pursuit of decarbonization goals.
I wrote here about the potential of advanced geothermal systems (EGS) nationally and in Pennsylvania. Now, the U.S. Department of Energy has released a roadmap for getting there.
Pathways to Commercial Liftoff: Next-Generation Geothermal Power finds that EGS could increase the nation’s geothermal energy production more than twenty-fold to 90 gigawatts—equal to about 10 percent of current U.S. electricity capacity—and potentially over 300 GW nationwide by 2050.
But there are significant challenges.
Besides reducing costs, DOE says EGS will need $20–25 billion in investment before 2030 to demonstrate commercial viability—a huge issue for a technology facing high up-front project costs and development risks—and perhaps ten times that to reach scale by 2050.
While most EGS development will occur in the western United States, Pennsylvania can play a key role. DOE says “multiple gigawatts” of EGS could be deployed in Pennsylvania, West Virginia, and Virginia as early as 2035, and suggests that demonstration projects in the region “could have an outsized impact on investor confidence.”
But there’s one more issue.
EGS development employs hydraulic fracturing, which the report acknowledges has “caused environmental harms in the past and can create community trust concerns.” DOE draws some distinctions between EGS and unconventional oil and gas development:
- hydraulic fracturing for EGS would use “fewer chemical additives”
- EGS wells are fully cased and cemented
- EGS reservoirs are generally much deeper, disconnected hydrologically from any groundwater or drinking water sources, and are overlain with much less permeable rock, making groundwater contamination from EGS “highly unlikely”
- EGS systems are closed-loop; subsurface fluids aren’t exposed to the atmosphere or drinking water supplies and won’t need disposal
- induced seismicity risk in EGS development “is mitigated” because injected fluids are also removed. (DOE requires that all funded projects follow an induced seismicity mitigation protocol.)
Still, the report calls for “early community engagement” on EGS projects and says that because the industry is at the pilot scale, “an opportunity exists to collaboratively develop processes and methods for reservoir creation that eliminate or minimize the use of hazardous materials.”
Meanwhile, federal legislation has already been introduced that would negate that opportunity.
Days before DOE released its report, Senators from Nevada, New Mexico, Idaho, and Utah—whose states have a lot of federally-owned land with geothermal potential—introduced their Geothermal Energy Optimization Act. Their stated goal was to “streamline permitting” and “put geothermal projects on an equal footing with oil and gas projects on public land.”
Cue George Santayana.
Among other provisions, the bill would establish a “categorical exclusion” from the federal Safe Drinking Water Act for drilling exploratory geothermal wells. That is, it would expand to geothermal test wells a provision of the Energy Policy Act of 2005—the infamous Halliburton Loophole—that stripped the federal Environmental Protection Agency of its authority to regulate hydraulic fracturing.
The loophole has allowed the oil and gas industry to inject known hazardous chemicals in proximity to underground drinking water supplies and keep information on their usage from becoming public.
The exemption has clearly harmed public health, though much remains unknown and uncertain, and much more needs to be done to understand the associated risks.
Even in the cause of decarbonization, exempting EGS exploratory wells from federal oversight is profoundly unwise and puts the camel’s nose in the tent for a full-blown development exemption.
To be sure, permitting reform is essential to achieving clean energy goals. But in pursuing the potential of EGS, we must not repeat the mistakes of the past—mistakes that continue to plague us. The categorical exclusion of hydraulic fracturing from regulation under the SDWA should not be expanded to include EGS—and should be eliminated entirely.
