Geothermal energy is essentially caused by heat.
This heat energy comes from anywhere between hot water to magma deep below the earth’s surface.
Geothermal energy is also part of the green energy team; it is clean, renewable, and better for human health and the environment.
How does geothermal energy work?
Geothermal heat pumps--consisting of the actual heat pump, the air delivery system, and a pipe heat exchange system–are buried under the ground near the building conducting the electricity.
The pump works to both cool off and heat up a facility.
The heat pump removes hot indoor air to the heat exchanger and leaves the building cooler. This can in turn create a source of free hot water during the summer months.
The heat pump also delivers heat to the house through the heat exchanger during the winter months.
Geothermal energy is a simple process of capturing steam from hot water to power electric generators.
What can geothermal energy be used for?
Geothermal energy is great for heating buildings, industrial processes (pasteurizing milk), heating water, and aiding greenhouse plant growth.
How are geothermal energy plants developed?
For the U.S., hot geothermal bodies of water are in the westward states, as well as in Hawaii and Alaska.
Geothermal plants often power turbines/generators by using steam taken from a body of water. They also use water to boil a substance (fluid), which vaporizes in the boiling and causes a turbine to turn.
Power plants drill holes into rocks in order to better capture steam.
Geothermal power plants regularly follow three designs:
1) The dry steam system uses the steam from hot water. It goes through the turbine and into a condenser. Here the steam is turned to water. The water that is being pulled is hot and, after the heat is used, the now-warm-water is returned to the heat source so that the resource life will be prolonged.
2) Another system depressurizes the hot water and turns it to steam which is then used to power the turbine.
3) The binary cycle system passes hot water through a heat exchanger and is then used to heat a liquid (isobutane) in a closed loop cycle. Isobutane is used because it boils at a lower temperature than water, therefore, it more easily converts to steam in order to power the turbine.
What are potential problems?
Geothermal energy can be harder to access and use in real-world application.
There is hot dry rock everywhere 3-5 miles below the Earth’s surface.
To access the energy, cold water is poured through one well and pushed through the hot earth, causing the water to heat up and then exit through a different well.
However, despite how plentiful the resource, there is no real application for the technology used to heat water this way.
There is also no technology that allows the heat from magma, the very deep and most potent source of geothermal energy, to be harvested.
Why geothermal energy?
As of 2013, geothermal energy created about 68 billion kilowatt-hours of electricity.
This amount is enough to meet the electric yearly needs of 6 million average U.S. households.
In some countries, such as Iceland and El Salvador, geothermal energy accounts for 25% of electricity produced.
These are smaller countries of course, but supplementing with green energy to cut back on pollution is exemplified by these countries using their resources.
Technology is developing to make geothermal energy more accessible and powerful.
While geothermal energy has room for development, it still holds promise.
As a green energy, it is clean, renewable, and prevents the continuation of fossil fuel greenhouse gas emissions.