The Great Forgotten Clean-Energy Source: Geothermal By: Zak Demko

Why Geothermal Energy? If we used all the geothermal energy available within 2 miles of the Earth’s surface, we could power America for the next 30,000 years. Just 5 percent within this same depth could meet the energy requirements for 260 million Americans. This would reduce our dependency on coal by 33%

Where can Geothermal Energy be Found? Nearly every state west of the bolded line has a geothermal source suitable for generating electricity. However, everywhere in the nation has geothermal sources that have other uses.

How is Geothermal Energy “Made”. Hot water or steam is piped to the surface to drive a turbine. This hot water or steam is usually used to heat an intermediate working fluid. This working fluid would turn turbine blades, which would drive a dynamo that produces electricity.

Problems with Geothermal Energy. Not every geothermal source is hot enough to produce water or steam that is over 200oF, which is the water/steam temperature needed to produce electricity. More expensive and less efficient than using coal.

Why Geothermal Energy? Experts say that improving exploration and drilling technologies could make geothermal power cheaper than coal. Uses a natural resource that will not lead to increased CO2 emissions.

Why Don’t We Currently Have Geothermal Energy? Low funding for programs to develop geothermal technologies. Low gas prices in the 1990s decreased the need for alternative energy sources, leading to funding to be cut during this period. The 2007 Energy Act authorized the DOE to spend $95 million for geothermal research, but Congress has appropriated on a fraction of that so far.

Other Uses for Geothermal Sources. Geothermal sources not hot enough for electricity generation can be used for geothermal heat pumps. Geothermal heat pumps transfer heat that is trapped underground to homes in the winter. In the summer, the direction can be reversed to cool the home.

Is Using Geothermal Energy Feasible? Iceland has the best geothermal energy network in the world. 85% of Icelandic houses are heated geothermally through the use of geothermal heat pumps. 5 geothermic plants provide 25% of the country’s electricity.

Future of Geothermal Energy. The private sector is beginning to push for geothermal energy in the United States. Last September the Nordic financial group Glitnir announced that it plans to invest $1 billion in the U.S. geothermal market over the next five years. Currently, 1 million homes have geothermal heat pumps. These pumps only cost $7,500 per home.