What is geothermal energy, and how can we use it in society?
Geothermal energy is the use of the Earths very own energy. It’s renewable, clean and can range to easily acquirable hot springs on the surface or hot rock found a few miles below the surface. Or you can go a bit deeper and hit the extremities of the molten rock (magma).
In the US around 80% of all geothermal hotspots are found on the western states i.e. Alaska and Hawaii. Wells are drilled deep into the underground reservoirs in order to use the steam to turn the turbines and generators. Others however use a liquid, which is boiled by the hot water why then vaporizes and turns the turbine.
The hot springs near or on the surface are used to provide heat to not only homes but to green houses, fish farms and industrial processes such as pasteurizing milk.
There are three ways we can use geothermal energy.
Direct Geothermal Energy.
This is where we use the near surface hot springs to be pumped directly into our houses and office buildings. It is pumped through a heat exchanger, which transfers the heat in the water to the heating systems of the buildings. Once the waters heat has peen used it is piped back into the spring and heated back up.
Geothermal Heat pump
Geothermal Heat Pumps are used to take the warmth from the ground (which stays at a constant 10-15°C all year). This heat alone is used to heat or cool homes and offices, the fluid flows in a series of pipes underground and then into a building, and then being looped back to the ground. But when it reaches the building it hits a heat exchanger, which absorbs the heat from the water and pumps it through the vents. When it is summer however the heat exchanger takes heat from the building and transfers it to the water that is then sent into the ground.
Geothermal power plant
A geothermal power plant works in three different ways. The first and most common is the “dry steam plants” which takes steam directly from the reservoirs and uses it to turn the turbines.
The second method is the “flash steam plants” which uses the near molten rock deep in the ground to turn the water into steam, which again turns the turbines.
The third method is “binary Cycle plants” which takes the near boiling water from the ground to a heat exchange, which exchanges that heat to another liquid, which will boil at a lower temperature than water. That liquid then turns to steam, which rushes up the pipes and turns the turbine.
Even though there are three different ways in which Geothermal energy can be used on a mass commercial scale it still only accumulates to just over 1% of all the worlds energy source. But many countries are turning towards this source for energy because it is both renewable and leaves no carbon footprint.
The history of geothermal energy
Geothermal energy has been used for tens of thousands of years, first by the Paleo-Indians in North America. The hot springs served as a source of heat and bathing and as a source of healing. When the European settlers migrated west across the American continent they drifted towards these hot springs in order to keep warm. After the discovery of Yellow stone in 1807 the city of Arkansas was built over a field of hot springs and in 1830 Asa Thompson made a business where he would charge a dollar for a bath in a hot spring. This was the first commercial use of geothermal energy.
This source of geothermal energy was again commercialized in 1862 when a businessman named Sam Brannan spent over half a million dollars into building a resort just south of the geysers (which are north of San Francisco, California), he called it the “Calistoga”. It included a hotel, bathhouse, skating ring and a racetrack. This is the first time geothermal energy has been used on such a large scale commercially.
In 1892 the residents in Boise, Idaho used the hot water springs near their village to...
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