The environmental impact of geothermal energy depends on how geothermal energy is used or on how it is converted to useful energy. Direct use applications and geothermal heat pumps have almost no negative impact on the environment. Direct use applications and geothermal heat pumps can actually have a positive effect because they may reduce the use of other types of energy that may have greater negative impacts on the environment.
Geothermal power plants have low emission levels
Geothermal power plants do not burn fuel to generate electricity, so the levels of air pollutants they emit are low. Geothermal power plants release less than 1% of the carbon dioxide emissions released by a fossil fuel power plant. Geothermal power plants further limit air pollution through the use of scrubber systems that remove hydrogen sulfide. Hydrogen sulfide is naturally found in the steam and in the hot water used to generate geothermal power.
Geothermal plants emit 97% less acid rain-causing sulfur compounds than are emitted by fossil fuel power plants. After the steam and water from a geothermal reservoir are used, they are injected back into the earth.
Many geothermal features are national treasures
Geothermal features in national parks like geysers and fumaroles in Yellowstone National Park are protected by law.