Problems and Solutions of Generating Electrical Power
As the revolution in communications change the world smaller, it makes a bigger market for all the nations. So economic growth spread around the world. This economical growth requires much more electricity. But it cause serious problems to environment and ecology, because the main method of generating electricity is using thermal power, which can cause greenhouse effect and air pollution. This essay will look at the problems caused by thermal power, and the solutions are put forward, it will then evaluate those solutions, and finally, I will put my thoughts forward.
Thermal power is always uses fossil fuels to generate electricity, such as coal, oil and natural gas, so fossil fuels are major resource in electricity generation around the world. There is research made by Energy Information Association of America. It shows that fuel energy account for about 65 percent of world electricity generation, and fossil fuels will be kept using in this proportion in the next 20 years (Myer, K, 2007). Another research made by world coal institute presents the importance of coal in global electricity generation, especially in developing countries. In China, coal has 79 percent of electricity now, and India has 69 percent. In South Africa and Poland, over 90 percent of electricity generated by burning coal (WCI, 2010). According to those researches, thermal power plays a major role in electricity generation.
This high percentage of using thermal power causes several serious problems. Firstly, its emissions cause environmental pollution. Burning coal emits sulfur dioxides which is the precursor to acid rain. Because coal contains sulfur, it combines oxygen into sulfur dioxide during combustion. Nitride is another pollutant emitted by thermal power plants, it will cause acid rain and damage ozonosphere. Secondly, carbon dioxide is the main emission of thermal power. Thermal power plants could emit about 2500000 thousand metric tons of carbon dioxide in only one year(U.S.EIA, 2010). Though carbon dioxide is not a pollutant, but it can lead to greenhouse effect. There are many gases in the atmosphere absorb heat from sunlight to keep Earth warm, this Natural phenomena called greenhouse effect, and carbon dioxide is one of those gases. Today, there is too much carbon dioxide in atmosphere, this makes greenhouse effect stronger and Earth warmer than usual. Even a little bit raise in
global temperature may cause problems for modes of life and relation to their environment. Thirdly, mining those fossil fuels destroyed landscapes, and it is a danger work to labors. Also, coal mining impacts environment a lot in many sides, such as soil erosion, dust, noises and water pollution (WCI, 2010). Finally, as the demand of fuel is growing in so many developing countries, coal, petroleum and gas are becoming less and less, and the use of coal is still increasing. We could see that those disadvantages of thermal power not only pollute environment, but also bring problems in social aspect.
It can’t be imaged that how could people live in modern society without electricity, so what can human do to those problems caused by thermal power. The best solution is finding new energy to generate electricity. There are many other energy have been used today, such as wind power, nuclear power, hydropower and tidal power.
Wind power use a wind turbine to change wind energy into electricity, and those turbines tend to be built together as “wind farms”. This is an efficient way to produce more electricity in the area that have strong wind. There are two types of wind farms, onshore and offshore. Onshore wind farms are always built at the top of hills, open plains and mountains. Offshore wind farms are located along coastline, usually 3 to 10 kilometers from land (Jessica Aldred, 2007). Wind is a form of solar power, so it is clean, abundant and renewable. But it also has some disadvantages. First, it has potential hazard to fish and birds. Second, it makes noise may disturb residents who live nearby wind farms. Third, its power is low for one turbine, and it cost a lot to manufacture a wind turbine (Godfrey Boyle, 2004).
Nuclear power plants work in almost the same way as thermal power plants, the difference is that nuclear power plants use nuclear reactor to make heat instead of burning fossil fuels. It does not emit sulfur dioxide, Nitride and carbon dioxide, and it is the most powerful energy have been discovered by human beings. But there is a problem to deal with nuclear waste, it is a difficult work to place the waste in a safety way.
Hydropower using flowing water to revolve a turbine connected to a generator. Dams are the most important part of hydro power stations, dams block the flow of a river,
than release water through the dams to rotate turbines by using water pressure between high level water and low level. Compared with thermal power and nuclear power, hydropower seems relatively clean and safe. But all large hydro power stations have impacts on nearby environmental habitats. This is because dams significantly hinder the flow of water, so it cause higher water level in upstream water system and lower water level in downstream at the same time.
Tidal power has something the same as hydropower, they all use different water level to generate pressure against the turbine blades, then the turbine will spin quickly to drive the generator (Godfrey Boyle, 2004). Though it is renewable and clean, it has the same disadvantages as hydropower. The same as hydropower, tidal power make water level different from usual, because tidal power need to construct a barrage. The changes of water level could cause the same problems as hydropower. There is a summary of potential environmental effects of the Severn scheme made by The Department of Energy (1987):
“The changes that will occur to the tides and currents during construction and then later during the operation of a barrage will cause changes in sediment characteristics and in the salinity and quality of the water. These factors have a major bearing on the estuary’s environment and ecology.”
Although all these responses have their own advantages and disadvantages, it seems easy to choose wind power as the best energy instead of thermal power. As a form of solar energy, wind power can’t be used up, and it is safer comparing with nuclear power. If hydropower is widely used in electricity generation, it raises much environmental challenge. On the other hand, wind power has a big defect that makes it can’t be the main source in electricity generation, this defect is its low efficiency. So the technology in wind power should focus on making a more powerful wind turbine. In conclusion, there is a common sense that everything has its advantages and disadvantages, so it is impossible to find a method in generating electrical power without any defect, the thing we can do is finding an energy with less disadvantages.
References
Myer, K. (Ed). (2007). Environmentally conscious alternative energy production. Hoboken, New Jersey: John Wiley & Sons, p.2.
Godfrey, B. (Ed). (2004). Renewable energy power for a sustainable future. UK: Oxford university press.
Nicole Bezic, K. (Ed). (2003). Renewable energy resources. USA: Smart Apple Media, 6-11.
Jessica, A. (2007, Dec 10). Where does wind power come from, and what are the arguments for and against wind farms? Jessica Aldred reports. Retrieved August 31, 2010, from
http://www.guardian.co.uk/environment/2007/dec/10/windpower.renewableenergy
U.S. Energy Information Administration (2010, January 21). Table 3.9. Emissions from Energy Consumption at Conventional Power Plants and Combined-Heat-and-Power Plants, 1997 through 2008. Retrieved August 31, 2010, from http://www.eia.doe.gov/cneaf/electricity/epa/epat3p9.html
World Coal Institute (2010). Coal & The Environment. Retrieved August 31, 2010, from http://www.worldcoal.org/coal-the-environment/
World Coal Institute (2010). Coal & Electricity. Retrieved August 31, 2010, 2010, from http://www.worldcoal.org/coal/uses-of-coal/coal-electricity/