Thursday, March 17, 2011

Geothermal energy – Quick facts

Introduction to geothermal energy

Geothermal energy is a very rich source of energy, as it lies directly beneath us, just a few kilometers below the surface of the earth. Geothermal energy is not connected with massive carbon emissions like this is the case with fossil fuels. Underground water near geologically active areas gets heated and even boiled at high temperatures and produce steam. The water is collected by drilling wells. The steam and hot water is separated. Steam is purified and used in power plants to generate energy. Water is used in reservoirs to produce more steam. This is a simplified example that explains the generation of geothermal energy. No fuel is consumed in the process of creating geothermal electricity and so it's emission free.

Geothermal power plants include: binary cycle power plants, hot dry rock geothermal energy, dry steam plants, flash steam plants, direct heat, and geothermal heat pump. The most common are binary cycle geothermal power plants, mostly because they have the large capacity for generation since the energy source (hot water) is constantly supplied. Geothermal power plants do not require large areas in fact they take up very small space compared to other power plants due to the fact that main components are underground pumping the water. One of the downsides connected with geothermal energy is the fact that fluids that are being used have low boiling points and are corrosive meaning that extra maintenance and care is required.

This brings us to the pros and cons of using geothermal energy.

Pros of Geothermal Power are as follows:
* The long tradition of direct geothermal energy use. Even in ancient times people have used geothermal power directly for purposes of taking baths, preparing meals, and heating their homes. Today, heating homes buildings is the most common direct use of the energy, and it's accomplished through use of district heating systems (geothermal heating is best developed in Iceland, especially in Iceland's capital Reykjavik). These systems pipe hot water into buildings from the surface of the earth, and are available for immediate use.
* None or very low greenhouse gas emissions. Fossil fuels when burns create massive carbon emissions that have not only resulted in climate change but also in acid rain and other harmful pollutants. With extra care geothermal energy can even be energy source 100% free of harmful greenhouse gas emissions.
* Geothermal energy is renewable energy source which means it will always be at our disposal because the earth continually replenishes our water supply through rain, and the earth's interior is in a constant state of producing heat.

Cons of Geothermal Power are as follows:
* Geothermal energy is still only scarcely used renewable energy source and most countries still do not make use of geothermal energy, and as a result, if you opt to install geothermal system in your home or office, it could become a very difficult to find qualified personnel for the job.
* Also when it comes to installation, wide spaces and long pipes are needed. As a result, areas of dense population will have a tougher time getting the energy into homes.
* Relatively high installation costs mostly due to the high drilling costs.
* Not a viable solution for all countries given current technological level, and still cost-effective only in areas near tectonic plates.

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