The heating of commercial and residential buildings in the United States is mostly dependent on fossil fuel sources such as natural gas. GeoVision, a U.S. Department of Energy study from 2019, found a tremendous market potential for geothermal district heating systems (GDHS). To date, most of the GDHS development, conventional or with heat pumps, has taken place in China and Europe. GDHS component manufacturing capacity in North America is not mature and significant increases in construction would likely require importation of European goods. This project attempts to expand market intelligence by simulating the cost for installation of modern European pipe, control, substations, and heat interface units serving a conventional GDHS in Helena, Montana. A shallow, low-temperature (< 75°C) surface manifestation, 2 kilometers from the service area, is the heat source.
Three production simulations with varying wellhead flow rates were made, then projected across a heat network using two simulation tools: GEOthermal energy for Production of Heat and electricity (GEOPHIRES) and Comsof Heat. Correlations between flow rates, heat losses, utilization factors, and costs indicate important variables for developer consideration. A cost profile was made using the average of these simulations. Exploiting a shallow, low-temperature heat source for a GDHS often requires greater investment in the heat network than the wellfield.
This project suggests North American geothermal developers must prepare for interdisciplinary GDHS projects that fall outside of their current business models. European DH operators and manufacturers can provide surface system expertise and materials while North America assesses subsurface exploitation targets. Bringing European DH professionals together with North American geothermal experts may help realize the potential of the GeoVision study, unlocking new business opportunities.