Hayden town leaders, the nonprofit Yampa Valley Sustainability Council and Routt County commissioners have advocated to the Colorado Public Utilities Commission that coal-fired Hayden Station be transitioned to electricity generation from deep geothermal heat.

Xcel Energy, the majority owner and operator of Hayden Station, currently is considering geothermal energy production as an option, according to Michelle Aguayo, Xcel media relations representative, in a May 20 email.

“We are studying the potential for geothermal power generation around Colorado including in Routt County and Moffat County,” Aguayo said. “We will submit this option, as well as other generation options, for bids in the upcoming Phase II process for the Just Transition Solicitation, which we anticipate will take place in the first quarter of 2026.”

“Based on the existing data, it would seem to support that there is a strong possibility that it (geothermal) would work,” Hayden Town Manager Mathew Mendisco said last week.

The coal-fired operation at Hayden Station is set to be retired by year-end 2028. Xcel Energy had previously announced investigations into other replacement energy generation options such as molten salt in 2021 and biomass in 2023, but those ideas have not advanced.

Yampa Valley Sustainability Council Energy and Transportation Director Paul Bony said Xcel transition plans for Hayden Station most recently included energy generation from wind, solar, long-duration battery storage and natural gas. The sustainability council advocates that moving to natural gas generation would create a fossil fuel asset that would become stranded among the ongoing movement to renewable energy.

The nonprofit council is “strongly in support” of the Public Utilities Commission allowing Xcel to explore enhanced and advanced geothermal electric generation at Hayden Station, Bony said.

“YVSC would like to see enhanced/advanced geothermal energy production at Hayden as a pilot program for Colorado, not the conversion from coal to natural gas generation,” Bony said. “The PUC has the opportunity to enable Xcel to explore geothermal electric generation and long-duration storage at Hayden.”

According to the International Renewable Energy Agency, Enhanced Geothermal System or EGS technology improves geothermal system permeability through hydraulic, chemical and thermal stimulation. The agency describes an Advanced Geothermal System, or AGS, as deep, artificial, closed-loop circuits where a working fluid is circulated and heated by subsurface rocks through conductive heat transfer.

Colorado entrepreneur Brian Dunn, founder of Pure Green Colorado, believes geothermal in Hayden is “highly doable.”

“Routt and Moffat counties are very attractive for geothermal generation and energy storage,” Dunn said. “The production of a coal facility can be replaced with geothermal with current technology in existence. The drilling and the geology and data points we have for that area are acceptable for us to proceed forward.”

Dunn said a geothermal energy generation project that utilizes heat from deep within the earth at up to 15,000 feet is possible in Hayden, and his company is one of a handful expected to submit project proposals to Xcel Energy. Dunn said his company is pushing forward to prepare a bid, including hopes of reusing some infrastructure from the existing coal-fired plant.

“What has helped us is the advancing technology for drilling that has helped to be able go deeper for cheaper,” Dunn said of engineered geothermal for utility-scale electricity production.

Another Colorado geothermal developer, Wendy Fenner, president of ZGEO Energy in Ridgway, pointed out that geothermal energy plants are not a new technology but have advanced with the help of technology growing through the oil and gas industry, as well as use of 3D subsurface modeling information gathered with the assistance of artificial intelligence.

Fenner said her company is planning for a geothermal energy project in western Montrose County, adding that geothermal energy production is active in California, Nevada and Utah.

Colorado Energy Office Geothermal Program Manager Bryce Carter noted in an interview last week that the minimum underground temperature needed to produce geothermal electricity starts at 250 degrees Fahrenheit. Carter said previous studies have shown temperatures of 250 degrees exist near Hayden at about 10,000 feet deep.

“The heat is there,” Carter said. “It just is a matter of how deep you go, and the deeper you go, the more expensive it is.”

The sustainability council is advocating for Hayden Station to become a demonstration site for the benefits of the next-generation geothermal technologies that are transitioning from niche to mainstream, driven by breakthroughs in drilling, reservoir engineering and hybrid applications, Bony said. The skilled labor needed to run a geothermal system parallels the current skills available in the Hayden workforce, Bony noted.

YVSC Executive Director Michelle Stewart noted in her public testimony at the PUC hearing on May 1 in Hayden that heat from deep underground temperatures would be a “stable, reliable and renewable energy source for electricity production.” Stewart said utilizing deep heat from the earth “makes economic, geologic and energy sense for our region,” adding that “geothermal generation and storage can be deployed on a timeline that meets the urgency of the Hayden transition.”

Already in Hayden, the Northwest Colorado Business Park near Yampa Valley Regional Airport and Hayden Station is progressing with drilling this month for a more traditional system with shallower geothermal resources as an energy source for heating and cooling in the business park, Mendisco noted. The bore holes could go to 800 to 1,000 feet.

“We are going much deeper to try to get to warmer temperatures,” Mendisco said. “If we get warmer temperatures, we don’t have to have as many bore holes. Our analysis is that the cost to go deeper versus the cost to drill more holes, the return on the investment going much deeper is much cheaper.”