Can We Use Electric Geothermal Energy in Connecticut?

Steam from the ground is evidence that geothermal energy is viable in the region.

Geothermal energy is available when heat deep within the planet rises relatively close to the surface. Heat flow gradient quantifies temperature differences between the surface and a specified depth. The greater the heat flow gradient, the more viable geothermal electricity generation becomes. Connecticut has a low heat flow gradient. This is not likely to change in the near future.

Geothermal Energy Source

Concentrated radioactivity, molten rock compressed and heated since the Earth's creation, and friction between tectonic plates contribute to underground heat. In order to be commercially viable, ground near the surface (few miles down into bedrock) needs to have a high heat flow gradient.

Heat Flow Gradient

Usable geothermal energy is like fossil fuels in the sense that some places have lots and others have virtually none. A high heat flow makes commercial use easier and cheaper. The geothermal heat flow map by Southern Methodist University indicates relatively small---40 to 50 mW/m3---heat gradients under Connecticut.

Power Plants

SMU's map shows that there are no geothermal power plants in or near Connecticut. Electricity from geothermal energy is zero or negligible. The Department of Energy's Energy Information Administration supports this conclusion, showing no electricity production through geothermal energy exploitation.

Future Prospects

Unless geothermal generator technology becomes efficient enough to exploit low heat flow gradients, prospects of geothermal electricity in Connecticut remain dim.

References

• Wesleyan University: Generalized Bedrock Geological Map of Connecticut
• Eastern Connecticut State University: Geothermal
• U.S. Energy Information Administration (EIA): Connecticut Renewable Energy Profile (2008 Edition)
• Southern Methodist University (SMU): Map of Geothermal Heat Flow