NATIONAL RENEWABLE ENERGY LABORATORY
NREL Researchers Bring Technical Expertise to Communities Selected for Geothermal Heating and Cooling Initiative

Initiative Will Provide Up to $13 Million To Accelerate Deployment of Geothermal District Heating and Cooling Systems to Diverse Range of Communities Across U.S.

Community Geothermal Heating and Cooling Design and Deployment Project Locations

More geothermal heating and cooling could be coming to a community near you, thanks to a new initiative funded by the U.S. Department of Energy (DOE) Geothermal Technologies Office (GTO).

This initiative will provide up to $13 million across two phases to support community-led geothermal solutions. The National Renewable Energy Laboratory (NREL) has been named subrecipient on four of the 11 communities selected for community-scale geothermal heating and cooling design and deployment projects.

NREL will assist communities in Colorado (Carbondale), Vermont (Middlebury), and Alaska (Seward and a remote community near Nome) to install district or networked geothermal technologies.

"These projects allow us to bring NREL's cutting-edge research and expertise to communities where transitioning to a clean energy source like geothermal will be most impactful," said Amanda Kolker, geothermal laboratory program manager at NREL.

The projects are focused on developing, designing, and installing new or retrofitted geothermal district heating and cooling systems that supply at least 25% of the heating and cooling load in these communities. The systems tap into the earth's subsurface to provide low-carbon heating and cooling to both businesses and residential spaces via an underground distribution network that uses a variety of technologies, such as district-scale geothermal heat pumps and direct-use geothermal (i.e., hot water).

NREL researchers are key to the design and implementation of these projects, which are part of the White House's Justice40 initiative to ensure that 40% of the overall benefits of certain federal investments flow to disadvantaged U.S. cities and neighborhoods.

These diverse communities showcase a range of system sizes, technologies, and geographies, providing expansive case studies that can be used to implement similar clean heating and cooling solutions in other communities. Selected projects will also identify solutions for improving environmental justice conditions and developing careers related to renewable energy sources through technical education and workforce transition initiatives.

"This provides a chance for us to apply our knowledge to support design and develop these systems," said Matt Mitchell, a researcher in NREL's Building Technologies and Science Center and NREL lead for the projects in Middlebury and Seward. "Our work here will help get these systems out there. It also helps us learn more about them and how these things can be done better in the future, which helps everybody in the long run."

Carbondale, Colorado

For the Carbondale project, NREL will partner with Clean Energy Economy for the Region, a nonprofit based in western Colorado, to install geothermal heat pumps. These heat pumps will support a net-zero district and will heat and cool several key buildings in the community, including school district offices, a library, 20 affordable housing units, a high school, a center for nonprofits, and townhomes. In addition, the project team is also taking into consideration what this transition will mean for the local workforce.

"The objective of this project is to replace natural gas throughout their energy district with geothermal pumps for heating and cooling so we can eliminate the environmental impacts of natural gas combustion," said Xin Jin, a researcher in NREL's Building Technologies and Science Center and NREL lead for the Carbondale project.

Middlebury, Vermont

In partnership with GTI Energy, a research and training organization focused on energy transitions, and Vermont Gas, NREL researchers will develop a geothermal system that will meet at least 50% of the heating and cooling needs of a new affordable housing development. This development will consist of townhomes, duplexes, and multiplex units, 30% of which are intended for low- and medium-income households. NREL researchers will provide guidance on the geothermal ground loop and underground thermal network of this project, designing the ground heat exchange system.

Seward, Alaska

NREL researchers will partner with the city of Seward, located on the Kenai Peninsula in south-central Alaska, to develop a community-scale heating and cooling system that will refine the existing design of the city's carbon-dioxide-based heat pump systems. A geothermal heat pump will be installed in the public library and then distribute hot water to several other municipal buildings in Seward. This new system will meet nearly all heating demand for half of the area's municipal buildings, using energy from thawed ocean water from nearby Resurrection Bay in a closed-loop geothermal heat pump system.

"It's kind of a proof of concept if we can do this, if we can do a district heat system for a small community in Alaska, then bigger communities can also follow suit and learn from our experience," said Robbin Garber-Slaght, a researcher at NREL's Alaska campus and NREL co-lead for the project.

Once the heat pump is installed, NREL researchers will help the community collect data to refine the operation of the new heating system.

Pilgrim Hot Springs, Alaska

Geographically isolated and with limited access to centralized energy systems, Pilgrim Hot Springs is a historic site located on the Seward Peninsula in Alaska, 60 miles from the city of Nome. While the area has been unoccupied for years, there are plans to revitalize this landmark as a year-round destination. A direct-use geothermal district-scale system to provide heating and hot water to buildings and cooling for food storage areas is a key part of this revitalization plan.

"The remote nature of the site makes this kind of project perfect for the area," said Georgina Davis, a project manager at NREL's Alaska campus and a lead on the project. "Geothermal is kind of the only option out there."

If successful, this project would bring economic renewal to the area and provide jobs in a remote part of the state.

Phase One and Beyond

The first phase of these projects will include designing the proposed community-scale systems, analyzing environmental and permitting needs, conducting feasibility analyses, and engaging with the community. Based on first-phase outcomes, DOE will select a subset of projects to advance to a second phase and deploy their systems.

Additional Community Support

In addition to the Colorado, Vermont, and Alaska sites, NREL has been assisting two other selected cities Ann Arbor, Michigan, and Duluth, Minnesota through DOE's Clean Energy to Communities (C2C) and Communities Local Energy Action Program (C-LEAP) technical assistance programs.

The Ann Arbor project will focus on creating a looped geothermal system, as well as efficiency improvements, rooftop solar, and battery storage, to heat and cool 262 households and other community buildings in the area. Meanwhile, the project in Duluth will use waste heat from a sanitary district to create a geothermal system that will cover 100% of heating loads in a disadvantaged neighborhood.

Learn more about NREL's geothermal research.