Research Corner: Thermal energy networks — 2,000 years in the making

We often equate "innovation" with the newest, flashiest gadget on the shelf. But sometimes, the most effective technology is the kind that’s already been refined for centuries. Geothermal heating is a perfect example: a Roman-era solution that remains an efficient way to power the modern world.

The Colorado Energy Office has granted $12 million since 2022 to spur geothermal development, supporting geothermal for single homes to district-wide networks, or thermal energy networks (TENs). Eligible geothermal projects may also qualify for state tax credits for a broad range of activities, from exploring wells to producing geothermal energy for personal or industrial use.

TENs are incredibly efficient in a number of ways beyond simply cutting heating and cooling costs. One reason is the source of heat. Geothermal ground source heat pumps are more reliable for heat than air source heat pumps, especially when temperatures drop, as they pull heat from underground, insulated from low air temperatures. Another effective advantage of TENs is that the infrastructure costs can be shared across participating properties. As networks grow, connected buildings with different heating and cooling needs can share excess heat without the need to generate new heat.

Communities with their own hot springs are well situated to establish their own TENs or at least utilize geothermal technology in certain developments. Pagosa Springs is the seventh largest geothermal heating district in the U.S., and they established a geothermal utility in 1982. The utility operates October through April, offering heat to its downtown area, including sidewalks.

Statewide, 40 TEN projects received Colorado Energy Office Geothermal Incentive Awards. These projects range from scoping and well exploration to installation, such as Colorado Mesa University’s network comprised of 16 campus buildings, providing geothermal heating and cooling to a total of 1.2 million square feet.

You can use this map to explore geothermal projects supported by Geothermal Incentive Awards across the state at various stages of development.