How it works: heat from inside the Earth is used to heat water and make it into steam. The steam turns a generator that produces electricity.
How much supply: one analysis claims that about 10% of the United States' electricity needs could be generated by geothermal energy.
Problems: the main problem is that geothermal energy is not available everywhere. There are a limited number of places where there are "hot spots" near enough to the surface to be used. Also, the technology for exploiting this resource is not yet very mature and so geothermal is not as feasible as it may one day become.
How it works
Geothermal energy is a particular category of heat energy, contained in the earth's crust. The more descending deeper inside the earth, temperature rise and geothermal energy theory can be used more efficiently.
It is interesting to note that 99% of Earth's interior has a temperature above 1000 ° C, and the remaining 1% is found at a temperature above 100 ° C. These elements suggest that within the Earth's is a renewable source of energy that deserves full attention and to be exploited as much as possible.
Geothermal energy is used on a commercial scale, starting around the 1920s, when it began to be used, in particular the heat from geothermal water, or from the geysers to heat homes or commercial spaces.In terms of potential heat, geothermal energy may be high or low potential heat.
High potential geothermal energy is characterized by availability at high temperatures and it can be turned directly into electricity or heat.
Nowadays electricity is get from geothermal energy in electric plants with power with 20 ... 50mW, which are installed in countries such as: Philippines, Kenya, Rica, Iceland, USA, Russia.
Low potential geothermal energy is characterized by availability at low temperatures and it can be used only for heating, being impossible conversion into electricity. Such geothermal energy is available even to the earth surface and is much easier to exploit than high potential geothermal energy , which is an advantage.
How much supply
Capturing the heat and transform it for use in heating of interior spaces is possible through a thermodynamic generator: Heat Pumps.
This equipment presents interesting performances during the winter because 1KWh of electricity consumed, heat pump return between 3 and 5 kWh of heat inside the house. A good part of the heating energy is provided as a free energy, renewable and clean, taken from land adjacent to the house.Summer, because of reversibility of cycle operation, the same equipment will extract heat from the inside and will inject into the soil.
Capture of geothermal heat is made using different methods, existing two categories of sensors: horizontal and vertical (geothermal drills). As with Heat Pumps, 1kW power consumed for powering the compressor is multiplied and harnessed in the form of 3 to 5 kW of useful rendered heat in the house, by heating installation.
Horizontal Picks of heating system (mounted in the ground adjacent to the house) require a minimum area needed, catchment area being in proportional relationship with heating inner surface .Picks once installed, plug digging and capture circuit becomes invisible. Land area over sensor must remain free of construction, permeable to rain water, snow, sun and wind for natural regeneration of soil heat (will not pave with slab of cement or asphalt).
Captured loops , once buried, have a durability for decades, with absolutely no further involvement. Minimum area of land adjacent to the building to capture geothermal heat is between 100-180% of the interior surface heating, depending on thermal power required for heating.
Concluding discussions about geothermal energy:
MINIMUM COST IN SERVICE! Heating costs will be drastically reduced, with up to 70% compared to traditional gas systems. Gas prices will grow in the future! For every 1 KW of electricity consumed, geothermal heat pumps have an exceptional performance and unmatched by any other traditional system.