By: Sahil Minhas
What is Geothermal Energy?
How can we use it?
~ Direct geothermal energy
~ Geothermal heat pump
~ Geothermal power plant
Hot water and steam from deep underground can be piped up through underground wells and used to generate electricity in a power plant. There are three different types or Geothermal power plants.
- Dry steam plants: Hot steam is piped into generators in the power plant from geothermal reservoirs. The steam spins turbines, in turn generating electricity.
- Flash steam plants: Water that's around 150 - 400 degrees Celsius is brought up through a well. Some of the water turns into steam, which drives the turbines and when the steam cools it condenses back into water and returns to the ground.
- Binary cycle plants. Moderately hot geothermal water is passed through a heat exchanger, where its heat is transferred to a liquid that boils at a lower temperature than water. When the fluid is heated enough and eventually turns into steam it spins the turbines.
Geothermal energy compared to other energy sources.
Geothermal energy is created right next to the plant so money is saved on processing and transportation costs. Also being more reliable as they run 24/7. Geothermal plant costs are usually high ranging from $1 to $4 million for each well to drill. The installation of a home geothermal pump system can be as much as $30,000, but can cut the energy bill by 30 to 40 percent, eventually paying itself off by 5-10 years.
Geothermal energy is renewable because the heat is continually replaced as the water that is removed is put back into the ground after being used. They are the best option because it can be used anywhere in the world because the temperature in the ground remains constant.