Geothermal

Geothermal Energy is heat (thermal) derived from the earth (geo). This includes (ironically) using the natural soil temperature to cool a home in summer and heat a home in winter (heat pumps)

Geothermal uses:

 

Electricity Generation

The highest temperature sources (greater than 150°C or 302°F) use steam to turn turbines that produce electricity. 46 of California's 58 counties have some type of geothermal resource. Current U.S. geothermal electric power generation totals approximately 2200 MW.

 

Heat pumps

Ground-source heat pumps use the earth as a heat source in winter and as a way of dispersing heat in summer. Using geothermal temperatures of 4°C (40°F) to 38°C (100°F), the heat pump transfers heat from the soil or water to the house in winter and from the house to the soil in summer. In effect, heats up a house in winter and cools it down in summer. Accurate data is not available on the current number of these systems; however, the rate of installation is thought to be between 10,000 and 40,000 per year.This can be used by any home because of the low temperatures required.

 

Direct Use

Direct use, as the name implies, involves using the heat in water sources whose temperature ranges from 38°C (100°F) to 149°C (300°F), for such things as heating of buildings, industrial processes, greenhouses, aquaculture (growing of fish) and resorts. Current U.S. installed capacity of direct use systems totals 470 MW or enough to heat 40,000 average-sized houses.
 

Geothermal energy from all uses places third among renewables, following hydroelectricity and biomass. Despite these impressive statistics, the current level of geothermal use pales in comparison to its potential. The key to wider geothermal use is greater public awareness, which is the reason for this web-site.

 

Statistics furnished by the Oregon Institute of Technology.