The Earth is very much a living and dynamic world and it is this fact that gives us geothermal energy.
Thousands of miles below the surface, a core largely composed of molten iron spins constantly and, combined with the natural radioactive decay of many of the minerals that make up the Earth's interior, there is an astounding amount of renewable energy just waiting to be tapped into.
This geothermal power is responsible for everything from hot springs to tectonic activity to volcanism and without it, life on Earth would not exist.
Geothermal power is one of the oldest known energy sources in the world. Only the Sun beats that.
Hot springs, for example, have been used since prehistoric times. Widely used by the Romans and even long before them, natural hot springs have been used to heat public baths and more.
Today, its application is far more extensive, however, with the increasing popularity of geothermal electricity which converts heat from this natural source into electrical power.
It is a relatively environmentally-friendly solution and it is pretty much renewable due to the fact that the Earth should remain geologically active for well over a billion years to come!
A great deal of Earth's geothermal power also resides in the crust, the outermost layer of the planet. The crust varies in depth between anything from twenty to forty miles.
Geothermal energy accounts for a great deal of energy in many countries in the world, including the United States, France, Turkey and New Zealand.
Some of this is down to direct geothermal power in which water is pumped from natural hot water springs to provide everything from hot water supplies to space heating.
The water is constantly in motion and being reheated every time it goes back to the geothermal reservoir.
Geothermal power plants use the heat from the Earth and turn it into electricity.
This may be done by using dry steam plants which use the steam to power turbines which in turn generate electricity in exactly the same manner that any steam engine works.
Geothermal power does come with its inherent disadvantages, however. While it is almost emission free, it is also very location-specific. Most of these locations are also a long way from the populated areas which most need the power.
Because of the long distances that the electricity has to travel, geothermal power is often not as efficient as it could otherwise be. Construction costs due to this, and the fact that geothermal power stations themselves are extremely difficult to build, are very high.
Nonetheless, the advantages largely outweigh the disadvantages, particularly when you compare geothermal energy to the dirty coal power plants and similar solutions which constantly belch out high levels of CO2 and require non-renewable fuel.
Whichever way you look at it, geothermal energy
will no doubt continue to play an increasingly important part in humanity's
ever-increasing energy requirement.