Good Essay About New Clean Energy Source: Geothermal Energy:
Clean energy alternatives are developed with the aim of reducing emissions, providing climate change solutions and securing a better and more sustainable future. The security, health and prosperity of future generations depends on the ability to break the dependence on fossil fuels such as petroleum, coal and natural gas by developing non-polluting and environmentally sustainable sources of energy (Ctcleanenergy.com). Clean energy is obtained from renewable sources that can be replenished constantly and sustainably (NRDC.ORG). Some of the clean, renewable sources are natural such as wind, water, sun, tidal waves and geothermal energy. Other sources arise from new innovative processes such as biomass conversion, waste-to-energy conversion and fuel cells (Ctcleanenergy.com).
Geothermal energy production and applications.
The paper discusses geothermal energy whose production relies heavily on seismic activities beneath the earth’s crust. There are various geothermal power plants around the world used to generate electricity using hot water and steam originating from underground reservoirs. Geothermal energy used in many areas of the world and as of 2013, the global geothermal energy production capacity was 11,700 MW (megawatts) and expected to double in 2014. These geothermal plants produced over 68 billion kilowatt-hours of electricity which is equal to the annual power consumption by more than 6 million U.S households. About 25% of the electricity produced in Iceland and El Salvador is from geothermal sources. The US has over 3300 MW of installed geothermal capacity spread over eight states, making it a global leader in geothermal production. Geothermal energy is also for clean and inexpensive heating and cooling of homes and commercial buildings in the United States (UCSUSA.ORG).
Currently, the best way of harnessing energy from geothermal sources involves tapping into geothermal spring (hydrothermal convection) systems where cool water seeps or is pumped into the earth’s crust, gets heated and rises to the surface again. Steam from the rising hot water is then captured and used to turn electric turbines. Geothermal power plants may drill their own holes to pump water into the earth and capture steam effectively. There are three geothermal power plant designs that capture steam and hot water from the ground then pump it back into the earth as warm water to sustain the heat source (Energy.gov).
The simplest design involves dry steam where steam is used directly to drive turbines, then condensed into water. The second design involves depressurizing (flashing) very hot water into steam which then drives turbines. The third approach is known as a binary cycle system where hot water passes through a heat exchanger that heats a second liquid with a lower boiling point in a closed loop. The liquid with lower boiling point e.g. isobutane is quickly converted to steam compared to water (Energy.gov). The Figure 1 below shows these three systems.
Figure 1 Geothermal power plant designs i.e. Dry Steam, Flash Steam and Binary Cycle Power plants (Source: Energy.gov).
Advantages and disadvantages of geothermal energy:
Geothermal energy has various advantages since it is environmentally sustainable, highly efficient, cost effective compared to fossil fuels for heating, renewable, more quiet than fuel fossil-run power plants, and finally, geothermal energy is always on and fairly constant unlike wind, solar and tidal wave alternatives (Bratley).
However, geothermal energy has its limitations such as availability since geothermal energy can only in countries with high geothermal activities. Establishment of geothermal facilities also requires significant initial investment for surveys, drilling, plant construction and developing power transmission infrastructure. While geothermal sources are considered environmentally friendly, open sources such as geysers can release harmful gases such Hydrogen Sulphide into the atmosphere. Pumping water back into the ground has the potential of cooling hot rocks beneath the power plant thus making them unable to reheat the water and produce steam to run the turbines. Failure of the geothermal site renders the site useless which results in significant financial losses (Bratley).
Conclusion and the future of geothermal energy:
Geothermal energy has the potential to move the world toward a greener and more sustainable energy future since it is one of the alternative clean energy sources that can deliver continuous and stable power. Additionally, unlike fossil fuel plants, binary power plants can be flexibly used to balance the power production fluctuations observed when using wind, solar or tidal energy. This is because binary cycle power plants can be ramped up or down to fluctuate production even multiple times in a day thus maintaining the net power production baseline (UCSUSA.ORG).
Bratley, James. 'Advantages of Geothermal Energy | Clean Energy Ideas'. Clean Energy Ideas. N.P., 2013. Web. 22 Apr. 2015.
Bratley, James. 'Disadvantages of Geothermal Energy | Clean Energy Ideas'. Clean Energy Ideas. N.P., 2013. Web. 23 Apr. 2015.
Ctcleanenergy.com,. 'Basics of Clean Energy, Renewable Energy Sources - Connecticut Green Bank'. Ctcleanenergy.com. N.P., 2015. Web. 22 Apr. 2015.
Energy.gov. 'Electricity Generation | US Department Of Energy'. Energy.gov. N.P., 2015. Web. 23 Apr. 2015.
UCSUSA.ORG. 'How Geothermal Energy Works - Union Of Concerned Scientists (UCSUSA)'. www.ucsusa.org/. N.P., 2014. Web. 22 Apr. 2015.