Geothermal energy produces little to no greenhouse gas emissions, which provides annual health and environmental benefits to the US valued at $278 million, according to an analysis from the Geothermal Energy Association.
About $117 million of those external benefits produced by avoiding fossil fuel emissions occur in California and Nevada, where the majority of geothermal energy plants exist.
The Air Emissions Comparison and Externality Analysis found binary geothermal plants produce virtually no greenhouse gas emissions. Dry steam and flash geothermal plants generate only trace amounts of emissions.
The analysis updates a 2005 paper published in the Electricity Journal and expands upon the methodology by incorporating more atmospheric pollutants into the calculation. The new information found the benefit of producing power using geothermal sources — as opposed to fossil fuels — is worth 3.5 cents for coal, and 1 cent for natural gas per kWh.
Geothermal energy provides additional benefits beyond avoided emissions, including less land degradation than other power sources, greater fuel diversity and improved national security by using a domestic energy source, the GEA says in its analysis. Geothermal power plants can use recycled wastewater to reduce environmental impacts on water resources and treatment costs.
The clean energy source has the lowest lifecycle emissions of any generating technology, according to the analysis. For example, dry steam and flash geothermal energy plants emit about 5 percent of the carbon dioxide, 1 percent of the sulfur dioxide and less than 1 percent of the nitrous oxide produced by a coal-fired plant of equal size, the GEA says.
Earlier this year, Senate Energy and Natural Resource Committee chairman Ron Wyden, D-Ore., introduced a measure to develop geothermal energy through the federal land leasing program. This legislation extends the authority for noncompetitive leasing in cases where a geothermal developer wants to gain access to federal land immediately adjacent to land with proven geothermal resources.