What is geothermal energy?
Earths natural energy is called geothermal energy. (Geo=Earth; Thermal=Heat). It is produced in the core of the Earth by radioactive reactions, where the temperature is more than 5000C. This heat is transmitted by the layers of the Earth towards the crust, which insulates us from the Earth’s interior heat. However, some amount of geothermal energy leaves the Earths surface; our Earth provides energy for millions of years. The Earths heat energy capacity is 12, 6 x 1024 MJ, and the crust heat energy capacity is 5, 4 x 1021 MJ.
In its simplest terms, geothermal means earth-heat. It is related to the thermal energy of Earth’s interior. On a large scale, the intensity of this thermal energy increases with depth, that is, the temperature of the Earth increases as we travel closer to its centre. A global average for Earth’s geothermal gradient (temperature increase with depth) is approximately 30°C/km. For example, if we merely removed the outer 3 km of Earth’s outer surface, it would be a sphere 5000°C at the core, and nearly hot enough to boil water on its surface. Earth contains an incredibly vast amount of thermal energy.
The word geothermal comes from the Greek words geo (earth) and therme (heat). So, geothermal energy is heat from within the earth. We can use the steam and hot water produced inside the earth to heat buildings or generate electricity. Geothermal energy is a renewable energy source because the water is replenished by rainfall and the heat is continuously produced inside the earth.
There are two types: High grade Low grade High-grade geothermal energy is the heat of the earth’s pressure that turns water into stream. Old Faithful at Yellowstone National Park is an excellent example. Low-grade geothermal energy is the heat within the earth’s crust. This heat is actually stored solar energy. ECONAR taps into this low grade geothermal energy and delivers big energy savings when heating, cooling and making hot water.
