Geothermal Energy

Geothermal, literally meaning Earth heat (Geo-Earth and thermal- heat) is a form of green energy derived from accessing heat reserves under the Earth’s surface. Geothermal energy generation involves drilling for underground water and steam that has been heated by magma. The water or steam is brought to the surface and used to turn turbines to generate electricity. Drilling technology is very similar to technology for drilling for oil and the geothermal industry draws on expertise from the oil industry.

Major Benefits:

The major benefit of geothermal energy relative to other green energy types is its reliability. While wind and solar are dependent on weather patterns, geothermal can be accessed 24 hours a day.

Uses:

Geothermal is used in power plants where heat is converted into electricity. Scientists and economists alike are excited about the potential for creating electric energy in an economic manner from geothermal energy

In addition to electricity generation, geothermal heat from relatively shallow geothermal sources can be used directly to heat greenhouses, heat buildings, dehydrate foods, heat streets and sidewalks to melt snow, pasteurize milk and heat water in fish farms.

Geothermal heat pumps to both heat and cool buildings are increasingly being used to simply transfer warm or cold fluids from a building to the earth and vice versa. Using temperature differntials between the earth and the heated or refrigerated areas of a building is an extremely efficient way to meet temperature needs, with very little additional energy needed to be added to the system.

MIT Study:

A comprehensive, 400 page study published by an 18 member panel led by Massachusetts Institute of Technology (MIT) and sponsored by the US Department of Energy called “The Future of Geothermal Energy,” which was published in January 2007 studied the environmental impacts and economic viability of Enhanced Geothermal Systems (EGS.) The study concluded that with government economic support and a commitment to research and development, the vast resource of subterranean heat could be tapped and used to create economically competitive energy across the United States.

Enhanced Geothermal Systems would simulate natural systems where water comes into contact with hot dry rock. The water is then pumped to the surface to generate electricity and then returned to the earth in a heat exchange system.

The MIT study predicted that with significant commitment to its development, EGS electricity production could near the 100,000 MW mark by 2050, becoming a major supplier of energy for the US market. The report further states that the monetary investment into R&D for geothermal is still less than the cost of one clean-coal plant.

Where:

The US is currently the world leader in geothermal energy production concentrated mainly in the Western States tracing the edge of the Pacific Plate where geothermal waters are closer to the surface. Nevada and California are the current leaders, with significant potential in Hawaii, Alaska, Arizona, Idaho, New Mexico, Oregon Utah and Washington state as well as in BC.

Sustainability:

Geothermal energy is an essentially sustainable energy source. The US Department of Energy states that “not a single geothermal field has been exhausted to date, although reservoir pressures and temperatures have slowly declined in response to production.” Having a proven track record at the Geysers in California, and the Wairakei in New Zealand, geothermal plants have been producing electrical power for forty years while the geothermal plants in Lardello, Italy have been producing power for over 90 years.