When it comes to the nation’s future power needs, geothermal energy checks many critical boxes. A renewable resource, it produces no greenhouse emissions and has a low environmental impact. Geothermal energy can be harnessed without importing fuel, and it produces energy around the clock; it could pave the way to increasing the nation’s energy independence.

With a decades-long history of researching and applying renewable energy sources, PNNL supports the U.S. Department of Energy’s Geothermal Technologies Office in growing the use of geothermal energy. PNNL projects related to these efforts include developing materials and methodologies that allow for improved reservoir characterization, well cement integrity and co-production technologies. Research also focuses on improving efficiency and reducing cost of low-temperature heat engines through enhanced working fluids, and on decreasing water use for stimulating rock shearing in enhanced geothermal systems (EGS).

Extraction through innovation

Using geophysical techniques and modeling capabilities, PNNL is characterizing potential geothermal sites and evaluating their capacity for long-term energy production. One of these sites is the Newberry Volcano, located in central Oregon, one of the largest geothermal heat reservoirs in the western United States. NEWGEN, a public-private consortium, is developing a new concept of super-hot EGS at this volcano with very high-temperature wells (above 450C). The project aims to test more efficient and innovative ways to extract underground heat where conventional geothermal power generation isn’t possible.

Ultimately, PNNL’s goal is to develop technologies that can better capture, extract, and convert heat from the Earth, making the energy produced more competitive in the marketplace compared to other sources of electricity. This will promote a more reliable, sustainable power grid, and increase the strength and productivity of the U.S. economy.