Free Science of Motion Essay Sample
Hydroelectric power is power generated by the force of falling water. A dam is created and water builds up behind it accumulating potential energy. This water is then rushed down a sluice transforming potential energy to mechanical energy when it strikes the rotary blades of a turbine. As the turbine rotates, it spins electromagnets which in turn generate current in coils of wire stationed strategically to transmit this current to a transformer. In the transformer, the voltage is increased then transmitted via power lines over long distances into people’s homes and offices. Therefore, hydroelectric power production is dependent on the availability of a large water body, falling water, and lots of land. The capacity produced largely depends on the force of the falling water available.
It is among the oldest methods of generating electricity and is still quite popular around the world. In the United States of America, it accounts for 7 percent of all the electricity produced in the country. Hydropower which is renewable is the most used source of energy.
Hydroelectricity has some advantages over other methods of producing electricity. One of them is that there is minimal pollution because fuel is not used. Water is the main resource used in this production and it’s freely provided by nature hence this kind of electricity production is often less costly. Its operation and maintenance costs are relatively low. Hydroelectricity has been used widely and for a long time and its technology has been proven over time and found to be reliable. A major advantage is that it is renewable, water is replaced by rainfall and therefore there is technically no depletion. Power plants which use fuel or oil cause a lot of pollution in addition to depleting scarce natural resources. There are also problems when it comes to disposal of waste especially for nuclear power plants.
Hydroelectric power generation however, is not devoid of disadvantages. It requires very high capital to implant, that is, high investment cost. In some cases there is need to displace population, inundate land or wildlife habitat, loose or modify fish habitat and sometimes it changes the quality of stream water for worse.
Hydropower does not pollute the environment but it has an impact on the environment. It affects the use of land, natural habitats in the area taken up by the dam and changes the environment indefinitely. In most cases a hydroelectric power has a dam and a reservoir. These many times affect fish population and obstruct their migration. Hydroelectric power operation may also affect the water temperature and the river flow. These changes sometimes bring harm to native plants around such areas and may also harm animals in the river and on the land. Reservoirs may cover agricultural areas, archeological areas, people’s homes; in general important natural areas. Therefore, building dams may require that people living in that area and around it to be reallocated. In some reservoirs, methane, which is a strong and harmful green house gas, may be emitted to the atmosphere. Hydropower requires a lot of water and land where a dam and reservoir have to be built in order to operate. This takes a lot of time, manpower, and construction in addition to being very costly.
Case Study Niagara Falls Hydroelectric power station
The idea of generating hydroelectric power from the mighty Niagara Falls was harnessed by William Birch Rankine in the year 1877. In 1892, permission was granted the Canadian Niagara Power Company to generate electrical power from the water on the Canadian side. They were also allowed to build a power station upriver of the Horseshoe Falls. A power house was built on Cedar Island and it took advantage of the river current flowing around Cedar Island. A concrete weir diverted into the river is used to divert the water which is channeled into the fore bay where it enters the penstocks and plunges 136 feet hitting the turbine below. The water leaves the turbine and drains into a long tunnel which flows into the lower Niagara River located at the base of the Horseshoe Falls. Presently operated by eleven generators it provides electricity for a vast majority.
The building of a hydro power station in this area had a huge impact on the environment. In the 1600s, the waters of the lakes and water bodies in the Niagara frontier flowed freely and untamed in the wilderness. There was an abundance of fish, wildlife and birds. The land was totally untamed and a natural habitat for wildlife and fish. The waters were pristine and crisp and besides the roar of the now Niagara Falls the atmosphere was tranquil save for animal and bird sounds.
The Niagara frontier was first occupied in the early 1600s by Neutral Indians who were farmers and fierce warriors. They began to till the land and enjoyed the constant supply of water and hence fertile grounds. There was need of course to farm, hunt and fish in order to survive. Gradually, the water began to get polluted by human waste, sewage and garbage. They settled and made homes along the banks of the Niagara River and hence all the waste was washed down the river. Eventually the industrial revolution took over and nature began getting polluted a gradual process that has led to today’s state of global warming and depletion and pollution of natural resources.
By the time the hydroelectric plant was built, it had become normal to dump waste into the Niagara River. Over the years the Niagara frontier has attracted tourists as well as numerous chemical plants and hydroelectric projects. Chemical poisonous waste was dumped directly into the river and this waste increased over the years with increased construction of chemical plants in this area. Initially the flow of water was enormous and was able to flush much of this poison downstream. However, as more water was diverted into the hydro electric power generating stations the flow of water significantly reduced so the Niagara River could no longer flush itself of toxic waste. The wastes build up to such high levels that they could be seen floating on the water surface of the river.
This poison began to kill fish and water life in general. There no longer was enough water to flush toxic waste downstream and the fish were trapped in fatal waste and their stocks greatly reduced. A lot of species disappeared and it became common to thing dead water fowls along the river’s shoreline. Plants also began to wither and die due to this toxic water. Toxic waste levels rose to such a level that populations living around this areas began to suffer serious health problems resulting from the toxins and poison around them.
With all the dumping and pollution the has been subjected to the Niagara river, it would take at least two centuries to rejuvenate it if all chemical dumping was completely stopped. The effect of this pollution could actually eventually adversely affect the hydro electric power plants. Hydro power is a renewable source of energy in the sense that the water after being used to generate electricity is not used up and can be recycled over and over. However, with the increased pollution, the Niagara River which has already begun to dry up and may actually get to a point where it cannot supply enough water for power generation. This is because the loss of plants and forestry will greatly affect the amount of rainfall received in that place.
There is also the risk of contaminating the soils so much so that they no longer support plant growth. This will not only affect the human population but also the wildlife which depends on these forests. Water life in the Niagara River is soon going to be extinct having seen the loss of many species of fish. The soils around the Niagara frontier like sponge absorb all this waste and become more intoxicated by the day.
While there are other renewable sources of energy such as wing and the sun, hydropower is still preferable when it comes to mass production and reliability. While we cannot rely on the sun to shine everyday unless it is summer, or the wind to blow every day, we can rely on the availability of water every day even though it may vary in amounts. Another advantage over the other renewable sources of energy is the fact that water can be stored and used later during times when water supply is minimal, while sun and wind energy cannot be stored and power can only be harnessed from them when they are available.
The adverse effects of hydro electric power production are avoidable and can be controlled. Globalization has brought in its wake an increased demand for energy use. While it is not possible to do away with hydro power it is important to realize that generating it at the expense of the environment would not be worthwhile.