Deep earth layers can be used in two ways for sustainable energy. One is by pumping water through a piping to those layers and the ambient temperature to leave to take, and then re-inflate. The other is a variant thereof which makes use of the hot water immediately which is on the deep layers is that by pumping directly on.
In both cases, the pumped hot water can be used to areas such as buildings, greenhouses and residences for heating after it is usually adjusted to a still higher temperature. However, the hot water can also be used for the generation of electric power. While for the generation of electric current high temperatures are needed, it is sufficient for most of the other applications with only relatively low temperatures.
The Earth is approximately 4.6 to 4.7 billion years ago by the contraction of particles in which an enormous amount of heat energy is released. That heat is still used today to a great extent in the earth. Geothermal heat occurs 30 percent stems from the residual heat. 70 percent is geothermal energy due to radioactive decay processes since many millions of years of heat are generated. The temperatures in the core of the earth is estimated at as many as 4,500 to 6,500 degrees Celsius. At 1000 m depth the ground almost anywhere a temperature of 35 to 40 degrees.
The heat from the deeper portions is conveyed by heat conduction and convection to the less deep layers, after which these can be used. Especially for power are areas with a high temperature interesting. In particular, it is the case in volcanic areas. In such regions are also volcanic activities where the temperature differs from other areas can reach hundreds of degrees. The hot water here is the basis for driving a turbine.
Geothermal energy is always available regardless of the time of day or the season or the weather. Depending on the depth is, however, there is a big difference in the temperature. At a depth of 5 to 10 meters, the temperature is roughly equivalent to the average annual temperature of the surface region. Temperature of more than 50 degrees occurs only at greater depths for. However, the temperature of the interior of our earth could theoretically be used to provide for the total of the energy needs. But so far, it is obviously still a long way. Yet geothermal longstanding used. As was used in Roman times hot water for bathing establishments. A more recent, but old example, the district heating network in France Chaudes-Aigues that has already been built in the fourteenth century.
Geothermal energy was first used to generate electricity in 1913 in Larderello in the Italian Tuscany. Count Piero Ginori Conti left there to build a power plant where turbines were powered by steam and could generate a power of 220 kW. Tuscany is well located for the use of geothermal energy, since in the region, the North African and the Eurasian plates meet and the magma is relatively close to the earth's surface. Because of that hot magma, the temperature of the soil is greatly increased whereby the use of the geothermal heat produces a high efficiency.