Geothermal power plants

By: Lisa Jones

Agung Pambudi (2010), the author of a blog posts on renewable-energy-sources-portal.com claims that geothermal power plants are needed as a form of sustainable energy. In the article, he described three different types of geothermal power plants that will utilize thermal pockets of heat within the earth’s surface in order to create electricity. The different types of plants included dry steam, flash steam, and two-cycle power plant. Agung Pambudi does not make arguments in why geothermal energy should be produced. He states that they are need but provides no arguments in why it should be implemented over current practices that are used to obtain electricity. Arguments against the use of geothermal energy in producing electricity are low efficiency rates, locations of the plant, and the amount of water needed for processing.
Geothermal power plants require very high temperature within the boilers in order to operate; it is often hard to reach such extreme temperatures. This process only allows the power plants to be approximately 10-23% efficient. This is approximately half of the efficiency of burning coal. Coal is about 43-47% efficient.


Majority of geothermal electricity plants need large amounts of water for its cooling process. In areas where clean water is scarce, large allocation of water put towards producing electricity could be detrimental to the people of the area. Natural resources such as water that are needed for human survival must be distributed wisely. Meaning that if a place is low in water, having a geothermal plant may not be in the best interest of the people residing in that given area.



Location of where the power plant would be is another issue that arises. The land around the thermal power source must be stable. There have been incidences where subsidence has been the result of a power plant. Areas were sinking of the earth’s surface has happened is Wairakei field in New Zealand and in Staufen im Breisgau, Germany. Earthquakes have also been a result of because of the water injection. Water injection is a process to expel unwanted waste, by liquefying it and injecting it back deep into the earth’s surface. A power plant in Switzerland had to be temporally shut down because of multiple seismic activity were detected within the first week after water injection. Stability of surrounding land is an important component in the opposition of geothermal energy because it can cause harm to individuals and consequences of earthquake and subsidence can affect the environment and the surrounding ecosystem. Many geothermal sources are located in the wilderness among the great beauty of nature. This brings up the question is the aesthetic value of the wilderness is more important than mans need for electricity. Is creating a power plant that destroys nature more important than conserving nature considering it is not efficient and may lead earthquakes and the earth sinking?



Agung Pambudi was able to explain the technical process behind geothermal energy plants but was unable to create arguments in why implementing these processes is better for the environment and superior to the more commonly used methods. I believe that geothermal energy is not worth operating at this time. More research is needed to be implemented to discover ways to retain stability within the land and to make improvements to the refining process in order to make it more efficient. Once the problem in land and efficiency are solved or at least reduced I believe that geothermal energy will be great alternative to burning fossil fuels. Fossil fuels emit a large amount of greenhouse gases into the atmosphere having geothermal electricity will reduce this amount because it emits less pollution.



References:
http://renewable-energy-sources-portal.com/sustainable-energy/sustainable-energy-geothermal-as-a-future-sustainable-energy-2/