The phrase “geothermal energy” has been around for hundreds of years. The term “geothermal” derives from the Greek words; geo (meaning earth), and therme (meaning heat). This instantly gives us the quick definition, “geothermal energy is heat from the earth”.
A common misunderstanding of geothermal energy lies in the source of this heat. The two sources which heat our earth are the earth’s core, and the sun.
The earth’s core is predicted to be between 3000 and 4000 degrees Celsius, and this heat warms the earth right up to the land beneath our feet, decreasing in temperature all the way.
The suns surface is approximately 5600 degrees Celsius. The heat from the sun only warms the first few meters of our earth, and then this heat is lost during the night.
So where does the misconception concerning geothermal energy actually come from? Well, many people believe that the fairly modern method of heating water by laying pipes under around 1 meter of earth, is geothermal energy. Many scientists disagree with this, as geothermal energy should be used to describe the heat energy dispersed by the earth’s core.
The variant of geothermal energy which comes from the sun, should really be described as a ground heat source, due to the fact that solar energy is only able to heat the edge of our earth’s crust, before the sun goes down and the heat is lost.
Over recent years, companies who used to promote “geothermal boilers” are now switching to the use of the term “ground source heat pumps”, as a ground source heat pump uses the suns energy, not the heat energy from the earth’s core.
The correct process of geothermal energy extraction is associated with geothermal power plants. This extraction is only made possible by drilling very deep holes into the earth, so they can reach a substantial level of geothermal energy to heat water and extract steam to drive turbines.
So, there we have the basic understanding of geothermal energy and the variant of this energy.