Using direct source geothermal groundwater for heating involves transferring heat from hot groundwater to a building system’s heating water. Efficiently using natural heat from the earth provides a sustainable heat source that does not burn fossil fuels or use large amounts of electricity.
The City of Alturas, California and the surrounding areas in Modoc County have extensive geothermal resources. Using this resource puts the heating costs under local control, brings revenue into the local area, and provides cost savings for the Modoc Joint Unified School District (MJUSD).
The California Energy Commission funded this project to construct an injection well and all necessary piping, controls, and other components to provide a functional geothermal heating system for three schools in the MJUSD. The system was also designed with additional heating capacity for other facilities in the future.
This project showed that direct source geothermal heating projects are a viable option for rural communities with available geothermal resources. With the system operating approximately six hours per day during the October through April heating season, the annual savings was estimated to be $37,000 by offsetting costs for heating oil. The system can provide approximately five times the necessary capacity to heat the three schools, so additional facilities can feasibly be connected in the future. The project is estimated to save $4.2 million, if further developed to maximum potential over the 30-year life of the system, making more money available to the school district.
MJUSD successfully completed a project that can serve as a model for other small, rural communities that want to use their local geothermal resources. MJUSD is extending the piping to a new hospital for the Last Frontier Healthcare District under another California Energy Commission grant (Agreement Number GEO-16-001), which also includes additional building retrofits and control system improvements to improve the efficiency of the heating system.
