ACGE Geothermal Energy

Yet again another piece of the puzzle.

Geothermal is not a new technology, it has been around for a very long time and there is more of it in the US then most people know. Geothermal energy is produced in three ways.

First is to tap directly into underground steam created by underground water heated by magma far below the earths crust. The steam is piped to the surface, used to turn a steam turbine which turns a generator. The steam is condensed back into water and returned through an injection well.
The second way of harnessing geothermal energy is through a flash steam system that draws very hot water from underground and then is depressurized or "flashed" into steam which can then be used to drive the turbine and the generator. The water is then returned to the ground.
In the third approach, called a binary system, the hot water is passed through a heat exchanger, where it heats a second liquid such as isobutane a closed loop. The isobutane boils at a lower temperature than water, so it is more easily converted into steam to run the turbine.

It is critical that the ground water be returned to the source, otherwise is becomes a non-renewable source of energy for obvious reasons.

This form of energy generation is possible in certain areas, especially in the "ring of fire" zone which for the US includes California, Oregon and Washington. Other potential geothermal energy sources are those areas where there is geothermal activity close to the surface such as Yellowstone National Park in Wyoming, Montana, and Idaho.
	Currently the United States leads the world in geothermal energy generation and generates 3000 megawatts in eight states. California leads the states in production currently providing 2.5 million homes with electricity from geothermal energy plants with 21 new plants on the drawing board to provide energy to an additional one million homes.

Geothermal energy needs to be pursued on a wider scale, it is an integral part of the solution to the burning of fossil fuels.

Another use of geothermal energy is ground source heat pumps or geothermal heat pumps. You can go to just about any location on the face of the earth, dig down about five to six feet and the temperature will consistently be between 48 and 58 degrees. A ground source heat pump system uses that consistent temperature to either heat or cool you home. When the temperature outside is 40 degrees, the 58 degrees comes in handy, when the temperature outside is 100 degrees, need I say more?

A geothermal heat pump system consists of indoor heat pump equipment, a ground loop, and a flow center to connect the indoor and outdoor equipment. The heat pump equipment works like a reversible refrigerator by removing heat from one location and depositing it in another location. The ground loop, which is invisible after installation, allows the exchange of heat between the earth and the heat pump.

The biggest benefit of geothermal heat pumps, or GHP's, is that they use 25%–50% less electricity than conventional heating or cooling systems. This translates into a GHP using one unit of electricity to move three units of heat from the earth. According to the EPA, geothermal heat pumps can reduce energy consumption and corresponding emissions up to 44% compared to air-source heat pumps and up to 72% compared to electric resistance heating with standard air-conditioning equipment. GHP's also improve humidity control by maintaining about 50% relative indoor humidity, making GHP's very effective in humid areas.

Because they have no outside condensing units like air conditioners, there's no concern about noise outside the home. A two-speed GHP system is so quiet inside a house that users do not know it is operating: there are no tell-tale blasts of cold or hot air.

The initial cost of a GHP is more then a conventional system, however, with the energy savings the system will pay for its self within five to ten years.