Decarbonizing Brownfields with Geothermal + Solar

Analyzing the potential for innovative renewable energy technologies in Missoula, Montana

Project Summary

Community; Missoula, Montana

Technical Assistance: Clean Energy Analysis

Former Use: Industrial/Commercial Businesses

Future Use: Mixed-Use Development with
Renewable Energy

The MRL Triangle site is a State Superfund site
associated with steel culvert fabrication, rail car
maintenance, and rail spurs. The City of Missoula is
using an EPA Brownfields Assessment Grant to
complete a Voluntary Cleanup Plan Environmental
Assessment (VCP-EA) towards delisting the site. The
City expects to sell the property to a master developer
to create a mixed-use development with residential
(both market rate and affordable), retail, and
commercial uses.

With redevelopment in mind, the City would like to
create a district energy system to provide non-fossil-
fired energy at the property. This energy can take the
form of a combination of geothermal energy utilizing
Ground Source Heat Pumps (GSHPs), as well as solar
photovoltaics (PVs).

EPA's Land Revitalization Technical Assistance

In 2022, the U.S. Environmental Protection Agency
(EPA) Land Revitalization Program provided contractor
technical assistance to support the City of Missoula in
preparing a clean energy analysis for MRL Triangle.
This analysis included energy modeling, ground heat
exchanger (GHX) modeling, district GHX modeling, and
solar PV modeling to quantify the energy consumption
and to design the solar PV and the district GSHP
system. The team applied this analysis to four
development scenarios: 1. Utilizing conventional dual
fuel, 2. Conventional all-electric, 3. High-performance
all-electric using air source heat pump (ASHP), and 4.
High-performance all-electric using GSHP.

A GSHP is connected to pipe buried in the earth. Fluid is
circulated through the pipe, and a heat pump inside the
building extracts heat from the fluid.

The analysis revealed that GSHPs are the most
efficient way to heat and cool potential buildings at MRL
Triangle. The clean energy report will serve as a
resource for the City of Missoula to advance
geothermal and solar technologies as they strive
towards decarbonizing future developments.

For more information, contact Tim Rehder, EPA Region
8 Brownfields Program, at Rehder.Timothv@epa.gov .

A Sample Flat-Roof Mounted Solar PV System

The Community's Challenge

Before pitching geothermal and/or solar energy to

potential developers at MRL Triangle, the City needed

additional analysis to determine the optimal

configuration of infrastructure, and to further refine cost

estimates.

Circulating warmed or cooled
fluid through GHX transfers
energy to / from the ground

SEPA

United States	Office of Brownfields and Land Revitalization

Environmental Protection

Agency	560-F-23-335


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