Custom Wind Energy in the Contemporary World Essay Paper Sample
Buy custom Wind Energy in the Contemporary World essay paper cheap
What is does and how it works
The kinetic energy of the atmosphere is an enormous potential source of mechanical and electrical energy. Human use extends back to around 2800 B.C. when the Egyptians made use of wind energy in sailing ships. The Persians began using wind power several centuries B.C. to grind grain. Later, wind power was used for water pumping by the Dutch and in medieval England (Tecco 2003).
In the United States, wind power utilization waxed and waned over the past few decades due to several factors. Wind power for agricultural water pumping came into widespread use prior to introduction of rural electrification and with the availability of small windmills during the 1920s and 1930s. With electrification, however, many windmills fell into disuse and were not replaced. Nevertheless, there are thousands of small individual wind turbines used in localized electric generation or in water pumping located throughout the nation, although the higher concentrations are found in farming and ranching areas of the central and Great Plains (Bisio and Boots 1997). This paper, by referring to a number of scholarly articles and sources, analyzes the wind power deployment in the contemporary world, concentrating on the technical characteristics of the wind energy, providing overview of the economic and environmental issues associated with the usage of this ‘green technology’, detailing the political as well as social perspectives stemming from the wind power employment, and outlining gaps and future directions in the current application of renewable energy.
On a commercial scale, wind power attained some significance since the 1970s with development of the large California wind farms at Altamont, Tehachapi, and San Gorgonio where over 17,000 wind turbines are in operation, many for more than a decade. At the international level, there are approximately 21,000 wind turbines with a combined electric generating capacity of over 4,000 megawatts located in Denmark, Germany, United States, India, and 16 other nations. In addition, several thousand small wind turbines generate electric power or pump water at farms and businesses (Bisio and Boots 1997).
In the United States, wind power is also being developed at sites in Montana, California, Colorado, Arizona, New Mexico, North Dakota, Iowa, Oklahoma, Maine, Minnesota, Vermont, and Wyoming, among others. Planned utility-scale wind projects are designed to produce 10 to 500 megawatts of electric generating capacity at each site with up to 1,000 wind turbines at the larger wind farms. A recently completed wind project at Green Mountain, Vermont, produces 6,000 kilowatts through 11 wind turbines. The project’s initial cost was 11 million dollars. Similar larger projects are under construction or planned in Colorado, Minnesota, Wyoming, and several other states (Gipe 2005).
Wind power technology improvements over the past five years have included more efficient rotor blades, generator transmissions, power controls, and other components that have increased overall turbine efficiency, availability, long-term capacity factor, and cost-effectiveness. Whereas earlier designs generated electric energy at rates up to 15 to 20 cents per kilowatt-hour some 15 years ago, present power costs have been reduced to around 5 to 7 cents per kilowatt-hour for large state-of-the-art wind turbines.
Commercial wind turbines have grown in size and complexity in recent years. For a typical modern 600-kw turbine, the average rotor diameter is around 43 meters. Capital costs are in the range of $300,000 to $450,000, or approximately $500 to $750 per kw, and annual electrical output at a site with average annual wind speed of 15 miles per hour is around 1.5 million kilowatt-hours for each wind turbine of this design (Gipe 2005).
Overseas, wind power contributes to the electric generating systems in Denmark, the Netherlands, Germany, and Great Britain. Wind power projects are also getting underway in India and Japan. Several of the major wind turbine manufacturers are foreign corporations based in these countries, such as Micon, Vestus, Nordtank, and Enercon. Suppliers of commercial-size wind turbines in the United States include Zond Systems, Bergey Windpower, Kenetech, and Carter Systems, among others (Tecco 2003).
b. Positive and negative aspects of using wind power
|Get a Price Quote|
* Final order price might be slightly different depending on the current exchange rate of chosen payment system.
One of the virtues of wind power systems is their modularity; that is, individual units can be added readily in a wind farm as needed. Another advantage is their portability; turbines can be quickly taken down and moved. Aside from their reliance on the natural renewable resource (wind)--these systems are completely free of environmental pollutants.
A drawback of a wind power system is its lack of consistency in operations. In other words, it cannot generate power when the wind is not blowing. Even at the best sites, the wind does not always blow uniformly, neither on a diurnal nor a seasonal basis. Electric utilities point out the lack of constant operations of wind power as a disadvantage; however, this feature is becoming less troublesome as utilities are developing some experience with wind systems (Gipe 2005).
Recognizing that the energy of the wind is proportional to the cube of the wind velocity, a critical criterion in wind project site selection is determination of the long-term wind characteristics of candidate sites. Wind direction and elevation above sea level are also important considerations in site selection. Site elevation can determine atmospheric density, which is also a determinant of atmospheric energy available at a site. Combined with wind direction data and wind speed profiles of each site, this meteorological information is needed for a full resource assessment of a candidate site.
In any practical sense, it is impossible to store electricity in any quantity. The lifespan of a kilowatt of electricity, from the place of its birth at a local power plant to the point it hits the consumer’s socket, is measured in milliseconds. In order for a grid to operate throughout a populated zone, such as the New York metropolitan area, a steady flow of electricity must be produced that just exceeds maximum expected demand. Matching supply and demand is a pretty fine art. Unpredictable supply, such as that supplied by wind turbines, does the grid no good and therefore is just ignored. Unfortunately, it cannot be totally ignored. To comply with government set targets for the production of renewable energy, wind generated electricity has to be purchased. In the real world, where it takes an hour and a half to ramp up a gas-fired turbine and a few days to power up a nuclear plant, planning to meet expected demand requires advance planning. Throwing wind power into the mix, which can vary in output with each gust or lack thereof, will never produce the consistent supply that would be necessary to take fossil-fuelled or nuclear plants offline (United States Government Accountability Office 2005). Reliability is the main problem with wind power. The other problem is that even when everything is working at ideal levels, wind power produces virtually no electricity.
In the January 2000 edition of Wind Power Monthly it was reported that at the end of 1999 there were around 40 000 turbines in the world, with a maximum output of 12 455 MW (United States Government Accountability Office 2005). Assuming this is a correct figure, and again assuming a 25% efficiency rate, the total electrical production from all these contraptions would satisfy less than 8% of the needs of the country like UK.
Another problem with wind power that is rarely brought up by its advocates has to do with simple mechanics. Although the internal mechanisms are getting better and better, the gear boxes wear out fairly regularly and there is a considerable amount of down time attributable to repairs rather than just a basic lack of wind. Considering all the subsidies the business has received from governments the world over, its lack of success is startling. Wind power would disappear immediately if subsidies were withdrawn. In the UK, wind power costs anything from 116% to 440% of the price of the conventionally generated power. In the USA, the figures are much the same, and these costs are passed right along to the consumers (United States Government Accountability ffice 2005). Although most consumers will never have their lights powered by the wind, they end up paying for it anyway. Whole areas of the south-eastern USA, which are considered unsuitable for wind power, have to subsidize the installation of turbines throughout the west and cast coasts (Etherington 2006).
Impact of wind power technology
a. Economic considerations
In the last few decades, strenuous efforts have been made to develop power systems based on renewable cycles of wind and water. Unfortunately, these can inherently only yield a supply which fluctuates with the natural driving forces, so that a steady and reliable power supply cannot be derived from such sources (Wizelius 2007).
Although it follows that the bulk of power supply to a highly industrialized country like the US must stem from other types of system, which respond reliably and rapidly to demand, the wind energy can be blended in the US Grid; it appears worthwhile to supply perhaps 10-20% of peak power requirements in this way (Milborrow 1985). A consequence, however, is that other types of power plant have to be operated at part load ready to cut in when such variable sources as wind and wave power are unavailable; this incurs an inherent economic problem.
There are several methods proposed for abstracting power from the motion of waves on the sea, e.g. Salter’s Duck, the SEA Clam, the Lancaster Flexible Bag and the NEL Oscillating Water Column (Wizelius 2007). These involve various energy transfer arrangements, such as floats which move up and down on the waves or changes in air pressure transmitted to turbines as water depths oscillate with the waves. All the methods obviously require a coastal location, preferably selected for good wave characteristics but, as an unfortunate consequence, severe storm conditions can occur. Considerable construction may be necessary, with long structures to derive an acceptable level of power. Further, the units may be spread over a wide area, albeit of sea. For example, it is calculated that the ‘clam bag’ unit of 10 MW(E) would require a 275-metre spine with 10 clams attached; the equivalent of a 2 GW(E) power station would then be 55 kilometers long (Wizelius 2007).
Wind power requires even larger areas, in order to avoid interaction between units. For example, the replacement of currently planned UK nuclear power by wind machines would need 10,000 square kilometers, 4% of the rural land area of England and Wales (United States Government Accountability Office 2005). Though there is a possible market for replacing diesel power units in remote parts of the UK, the impact of general application on land would therefore appear unacceptable. Offshore sitting, say at depths of 10 to 50 meters is therefore indicated, but this, in turn, introduces extra complexity in construction and maintenance, with associated increases in costs. It has been suggested that the UK could construct 2,000 wind machines, each of 8MW(E) in shallow coastal waters and several thousand smaller units on land (Wizelius 2007).
An inherent technical feature is the sensitivity of power output to wind speed. No power is produced with winds of less than about 15 mph, but output is proportional to the cube of the wind speed thereafter. Environmental problems include electromagnetic interference to radio and TV transmissions, noise, visual effects and the impact on bird life. Nevertheless, the UK Central Electricity Generating Board (CEGB) has been increasing its research commitment to wind power (Milborrow, 1985).
A review of wind power (Milborrow 1985) suggests, for average onshore sites, costs in the range 3.2p to 3.5p/kwhr, which is on the CEGB Sizewell figures of Section 8.3.3, wind power would be cheaper than coal. However, the number of such sites is limited and costs increase substantially as offshore farms are considered. The Severn Barrage study by McAlpine concluded that 5% of UK power could be supplied at a similar generating cost to Sizewell (Milborrow 1985). On the other hand, a 1982 Department of Energy study concluded that the best form of wave power is unlikely to produce electricity at less than 5p/kwhr. The Camborne School of Mines investigations of ‘hot rocks’ suggest a figure of 4.2p/kwhr for geothermal power in favorable areas if heat extraction at 6-kilometre depths were to prove feasible (Tecco 2003).
In the developing systems, fusion requires very large experimental units for testing possible power processes, so that considerable international co-operation and long timescales for research are necessary. Several companies are offering commercial wind machines in the 60 to 300 kilowatt range; larger machines are under test in the UK, but there seems to be no concept of energy storage to overcome the shortcoming of intermittent power supply. ‘Wind farms’ are planned in various parts of the UK, but large areas are needed, many in regions of designated natural beauty. Wave systems, particularly those located on the coast, are under active development but will probably be appreciably more expensive than wind systems; some Norwegian concepts have interesting features (Wizelius 2007).
Wind power perspectives
a. Political implications and influence of using wind power
Despite the criticism of wind power, a number of authors advocate and support the usage of this green alternative technology (Tecco 2003). Ratification of the Kyoto Protocol, although without the participation of the US, will encourage the growth of a number of new businessses geared to sustainability. Today’s industries of the future include wind power, solar energy and fuel cells, all designed to replace older, polluting technologies. The world’s major financial centers, New York, Tokyo and London, are all well aware that emissions trading could become a major business opportunity.
One of the key drivers behind the increased use of renewable energy is global deregulation of electricity distribution, which in turn enables consumers to choose green electricity. In California and certain parts of Europe consumers can do so for a premium price, while in Germany houses generating their own solar energy are able to sell surplus electricity to the national grid at a profit. The US does not have the same kind of national grid, but 36 states have agreed to offer some kind of net metering. This means that homes generating solar and wind power can offer it to the local power company, and draw down the credits when they need to. This was not possible in the UK until liberalization of the power supply market occurred in 1999 under compulsion from a European directive (Wizelius 2007). From that date, over ten suppliers have offered green energy for a small premium of 3–10%. The way the system works in the UK is that a supplier anywhere in the country can provide electricity to a customer in a distinct geographical region. Under the green tariff system, the supplier agrees to supply the National Grid with electricity guaranteed to be produced from renewable sources equal to the units of electricity their customer has used.
In November 1999 Scottish and Southern Energy launched a scheme in association with the Royal Society for the Protection of Birds (RSPB) to offer green energy across the UK at the same price as conventional brown energy. Both parties benefited from this arrangement. Scottish and Southern became the first major utility company to offer green energy at nil premium, while the RSPB received a fee from the company for each household switching to its services (Wizelius 2007). A survey in 2000 found that 60% of consumers in Sweden and Germany would be prepared to pay a premium of up to 2% for green energy, while 50% of consumers in the UK would do so. That said, the highest take-up rate of green energy in the EU is in the Netherlands, with 140 000 customers or a 2% market share. In the UK it is insignificant, less than 0.1% of UK households (Tecco 2003).
Continental Europe has taken a leading place among the major economies of the world in actively seeking to replace coal and gas by renewable energy sources. In May 2000 the European Commission (EC) issued a directive requiring national governments to promote the use of renewable energy, such as solar power, wind power hydroelectric power and biomass, by setting output quotas and offering financial incentives to producers of ‘green power’. The directive set the EC’s aim of increasing the proportion of EU total electrical consumption generated by renewable power from 13.9% in 1997 to 22.1% by 2010. This included doubling non-hydroelectric supplies from 6% to 12% of the total. To put this into perspective, only about 1% of the world’s total power capacity was produced from renewable sources by the end of 2001 (Tecco 2003).
When he took office, President George W. Bush seemed to have little interest in renewable energy, as shown by his national energy policy unveiled in April 2001. However, the events of 11 September 2001 seemed to have modified that position. The administration became aware that US domestic oil and gas production was running down, leaving America increasingly vulnerable to energy supplies from the Middle East. It realized that encouraging the US to build up its supplies of renewable energy was one way of reducing this strategic risk. It therefore took a modest step in this direction with the Clear Skies Act, presented to Congress in February 2002 (Britain Follows the Winds of Change 2001). This proposed mandatory curbs on emissions of sulphur dioxide, nitrogen oxides and mercury by US power stations, and suggested measures to encourage emissions trading. However, the act ignored existing congressional proposals to put limits on carbon dioxide emissions (Britain Follows the Winds of Change 2001).
b. Social implications of using Wind energy
Wind power has emerged as the main source of renewable power in Europe. In 1999 the International Energy Agency (IEA), an arm of the OECD, reported that installed global wind power capacity had reached the ‘historic milestone’ of 10 000 megawatts. European countries were the leaders in this area, notably Germany, Denmark and Spain. Germany was the world leader with an installed base of 6100 megawatts of wind power, including 1600 megawatts installed in 1999 alone. While wind power subsidies have cost the German government around 2 billion a year, the emerging industry is also believed to have created some 35 000 new jobs. Spain came second with an installed base of 2500 megawatts, although the Spanish government’s encouragement of wind power meant that it was the fastest-growing wind power market in the world, while Denmark was third in Europe with about 2100 megawatts of wind capacity (Gipe 2005).
Given Europe’s lead in this area—in 2000 it accounted for 70% of the global installed base of wind power—it is hardly surprising that Danish and German companies dominate global wind turbine manufacture. The investment bank Dresdner Kleinwort expects global wind power generating capacity to reach 400 000 megawatts by 2020, equal to 200 conventional power stations (Gipe 2005). France appears to be set for very rapid growth. Although only 55 megawatts of installed wind power capacity existed in France by the end of 2001, the government has recently passed similar fiscal incentives to those existing in Germany.
The UK economy is not known for its technological leadership, and it lags well behind the rest of Europe in renewable energy output. In 1999 this stood at the relatively low level of 2.6% of the UK total, mostly deriving from old hydroelectric systems. However, in August 2001 tougher renewable energy targets for UK power suppliers were announced: all licensed electricity suppliers would be obliged to provide 3% of their sales from renewable sources by March 2003, rising to 10.4% by 2011. Suppliers would receive green certificates verifying how much renewable power they had bought, while companies falling below target would have to pay a penalty of 3 pence per kilowatt-hour. Since electricity produced by natural gas costs about 2 pence/k Wh, whereas renewable energy costs vary from about 3 pence/k Wh to 5 pence/k Wh, the idea was to make renewable energy cost-effective. The power industry lobbied hard to have electricity generated by incinerating waste classified as ‘renewable’, but this was rejected by the energy minister (Britain Follows the Winds of Change 2001).
In March 2001 Prime Minister Tony Blair announced that the government would spend £100 million to promote renewable energy in the UK. It is generally accepted that offshore wind power appears to be the most likely source, as research shows the UK’s climate to be the best for offshore wind power in Europe. The potential of offshore wind power has been calculated at 30 000 megawatts, three times the UK’s current power consumption (Gipe 2005). In April 2001 the Crown Estate, which owns the rights over the UK seabed, announced 18 leases had been granted to construct 18 wind farms off the British coast, which provided about 1500 megawatts by 2004, or some 5% of the UK’s total energy requirements. The government’s commitment to wind power was demonstrated by an announcement in November 2001 of the planned construction of a 400 mile cable linking the main offshore sites to the national grid (United States Government Accountability Office 2005).
Onshore wind power is a more attractive proposition in the US, a result of relatively low population density and cheap land prices. About 12 000 small inland wind power systems were built there in the 1980s, aided by federal tax credits, so that total US wind power capacity at the end of 2000 was about 2500 megawatts, the same as in Spain. However, while they were price competitive when built, a collapse in the natural gas price made wind power uncompetitive in the 1990s, and few wind farms were therefore built during that decade. However, advances in technology have halved the cost of onshore new wind power to 2 cents per kilowatt-hour, significantly below natural gas when its price rose sharply in 2000–2001. Renewable energy was made more attractive in 2001 to US consumers by the federal power tax credit (PTC), which gave a credit of 1.7 cents/k Wh. As a result, 2001 saw rapid construction of US wind farms for the first time for over ten years. A good example was the 470-windmill Stateline project on the border between Washington and Oregon, built by FPL Energy and due to produce 300 megawatts on completion (United States Government Accountability Office 2005).
Trends in the wind power application
a. Gaps in the current usage of wind power technology
In the industrialized nations, high levels of energy utilization have been a major factor in achievement of high standards of living. However, only recently have energy issues attained much visibility in the formulation of governmental policies. Some industrialized nations and, to a lesser extent, a few developing countries are beginning to realize the importance of employing integrated approaches to energy utilization in overall economic and social development. France, for example, with its limited fossil fuel resources, made a conscious decision some three decades ago to emphasize the use of nuclear energy in its electrification program. Today, more than two-thirds of its electricity is provided by nuclear reactors.
Japan’s limited land base and natural fuels have led to an electrification program consisting of fossil-fired plants using imported fuels as well as development of nuclear power plants.
China, by contrast, has significant coal, oil, and other resources as well as extensive water resources. It has embarked on an energy program that includes a mixture of nuclear reactors, coal-fired power plants, and hydroelectric projects. One of the latter, the Three Gorges Project, will be among the largest hydroelectric projects in the world and will impound a large river system for electric generation and flood control. However, the project will displace over 1.5 million people and may result in massive ecological disruptions. It seems unlikely that such a massive environmentally questionable project could be built in a noncommunist nation under public scrutiny and environmental regulations (Wizelius 2007).
For much of the postwar period, the U.S. government has given not much more than lip service to the subject of energy and then only during a crisis such as the 1973 oil embargo by the Organization of Petroleum Exporting Countries. Following World War II, Congress was euphoric about the great potential of atomic energy and created the Atomic Energy Commission to spearhead national efforts in developing peaceful applications of atomic energy. This agency was quite successful in spawning development of the commercial nuclear power reactor, in aiding the medical and industrial applications of radioisotopes, and in conducting research on advanced nuclear concepts such as the breeder reactor and nuclear fusion (Tecco 2003).
Aside from its efforts in atomic energy, the federal government has done little to foster innovations in fossil fuels utilization and virtually nothing in wind energy systems until the past decade or two. Following the breakup of the Atomic Energy Commission during the Nixon administration into two independent agencies, the Energy Research and Development Administration and the Nuclear Regulatory Commission, federal efforts continued to concentrate on commercialization of atomic energy with only quite modest investments in other areas of energy research and development, notably the Offi