Colorado hydrogen, geothermal poised for big growth, studies show

Colorado’s investment in geothermal energy will produce a handful of utility-scale hot water electricity plants in the next few years, according to studies released Monday by Gov. Jared Polis and his energy leaders.

The state can also launch effective hydrogen energy projects relatively soon, if the Energy and Carbon Management Commission and other regulators flesh out a series of needed safety and environmental quality rules later this year, the studies said.

“I am highly confident that we will see some geothermal electric capacity come online in Colorado in the next several years,” Polis said in releasing the studies, which raise the state’s resources and regulatory and safety challenges in both geothermal and hydrogen power.

State officials see fast-growing solar and wind power as the “workhorses” of Colorado’s electric grid in coming years, but they also say Colorado needs additional renewable technologies like hydrogen and hot water power to be instantly available backups to other sources.

Colorado has grants in place for test drilling and other research to solidify the earliest plans for new geothermal projects, and those initial efforts now show great promise for large-scale harnessing of underground heat sources. Small-scale residential or office geothermal heat is already growing for use in ground source heat pumps and neighborhood-scale hot water heat.

In a utility-scale geothermal project, deep wells would tap into Colorado water reservoirs that run at constants near 300 degrees Fahrenheit. In a binary-cycle plant, that hot water runs through a heat exchanger with a liquid that boils into gas at a lower temperature than water; the pressurized vapor then runs an electrical turbine.

The three most promising projects in Colorado are in La Plata County, near Pierce in Weld County, and at Mount Princeton, long known for its surface hot springs. Pierce could start at 3 megawatts of power and scale up to 180 MW, Colorado Energy Office director Will Toor said. La Plata County’s project will start at 20MW and could move up to 55 MW. The Mount Princeton project could be 10MW, Too said. By comparison, many community solar projects are about 5 MW to 10 MW; electric co-ops often build 20 MW solar arrays; and the largest utilities are commissioning solar arrays at 100 MW to 200 MW.

Hydrogen, which can be burned directly as a furnace or utility fuel, or used to power electricity-producing fuel cells without combustion, also holds promise to fill gaps in Colorado’s renewable energy mix, the studies said. Cleaner-burning hydrogen fuel could solve hard-to-decarbonize industries that require high heat, such as cement and steelmaking. Hydrogen can also be stored underground, in stationary tanks or in mobile tanks, and could be a clean shipping fuel for transportation formats such as long-haul trucking or ocean cargo.

Hydrogen fuels could provide 10% to 20% of Colorado’s overall power needs at some point, the study estimates. However, new safety and commerce regulations are necessary; hydrogen is buoyant and dissipates quickly, has a low ignition point, and if pressurized into liquid form demands extremely low temperatures that make equipment and pipelines brittle far sooner than other fuels.

A key rulemaking for future geothermal production begins in early August at the energy commission, commission director Julie Murphy said.