Wind power is the conversion of wind energy into a useful form, such as electricity, using wind turbines. At the end of 2007, worldwide capacity of wind-powered generators was 94.1 gigawatts. Although wind produces about 1% of world-wide electricity use, it accounts for approximately 19% of electricity production in Denmark, 9% in Spain and Portugal, and 6% in Germany and the Republic of Ireland (2007 data). Globally, wind power generation increased more than fivefold between 2000 and 2007. The principle application of wind power is to generate electricity. Wind power has become increasingly popular recently because it does not involve burning fossil fuels, utilizing wind power to generate electricity without emitting greenhouse gases into the atmosphere. Questions, however, remain regarding wind power. The main question is whether it should be a major component of 21st century plans to combat global warming? Should it be prioritized among the various alternative energy sources? Additional questions frame the debate: Is wind energy a 0-emission alternative source of energy? While it may emit no greenhouse gases during the generation process, does the manufacture and transportation of wind turbines do so? Is wind power generally an efficient and powerful source of energy production? Can it produce enough electricity to help replace coal, one of the main contributors of greenhouse gases to the atmosphere? Do wind turbines threaten birds? Are the number of birds killed by turbines relatively insignificant? Should it matter, particularly in the context of the larger threat of global warming? Are wind turbines economical and viable in the market place? Are they viable enough to scale and produce massive quantities of energy? If not, should governments step in with subsidies? Are offshore wind turbines a good idea?
See Wikipedia’s article on wind power for further background.
A study by the Irish national grid stated that “Producing electricity from wind reduces the consumption of fossil fuels and therefore leads to emissions savings”, and found reductions in CO2 emissions ranging from 0.33 to 0.59 tonnes of CO2 per MWh.
Natural gas is a significant contributor to electricity generation. Yet, because it is transportable, it could be better used in cars. Therefore, wind energy, by contributing to overall electricity generation, could help free up gas to be better applied to powering cars.
Windmills are a visible reminder of the importance of protecting and preserving the environment. Few green energy resources are quite as visible and capable of reminding humans of the crisis of global warming and the need for humans to take action to reverse it.
When the wind is not blowing, back-up sources of energy will have to supply the grid. Some argue that these back-up sources will be coal and other dirty energy sources. But, this need not be the case at all. There is no reason why clean sources – such as solar, geothermal, tidal, and even nuclear – can’t back-up wind energy.
“Wind energy is only able to replace traditional power stations to a limited extent. Their dependence on the prevailing wind conditions means that wind power has a limited load factor even when technically available.”
“The environmental benefits of wind are not as great as its champions claim. You’ve still got to have backup sources of power, like coal-fired plants.”
“the carbon emissions associated with manufacturing, transporting and servicing windmills, and there is a carbon cost of some magnitude.”
“Excessive subsidies make them an expensive and inefficient way of reducing greenhouse gas emissions, a study by the Renewable Energy Foundation (REF) think-tank says.”
Wind energy is as sporadic and inconsistent as the wind. This may mean that electrical grids can’t handle wind energy. If this is true, wind energy is not a viable solution to global warming.
“Danger to birds is often the main complaint against the installation of a wind turbine, but actual numbers are very low: studies show that the number of birds killed by wind turbines is negligible compared to the number that die as a result of other human activities such as traffic, hunting, power lines and high-rise buildings and especially the environmental impacts of using non-clean power sources. For example, in the UK, where there are several hundred turbines, about one bird is killed per turbine per year; 10 million per year are killed by cars alone. In the United States, turbines kill 70,000 birds per year, compared to 57 million killed by cars and 97.5 million killed by collisions with plate glass. An article in Nature stated that each wind turbine kills on average 0.03 birds per year, or one kill per thirty turbines.
The Royal Society for the Protection of Birds (RSPB) supports the increased use of wind power, “as long as wind farms are sited, designed and managed so they do not harm birds or their habitats”.
In the UK, the Royal Society for the Protection of Birds (RSPB) concluded that “The available evidence suggests that appropriately positioned wind farms do not pose a significant hazard for birds.” It notes that climate change poses a much more significant threat to wildlife, and therefore supports wind farms and other forms of renewable energy.
“Whooping cranes have waged a valiant fight against extinction, but federal officials warn of a new potential threat to the endangered birds: wind farms.
Down to about 15 in 1941, the gargantuan birds that migrate each fall from Canada to Texas now number 266, thanks to conservation efforts. But because wind energy has gained such traction, whooping cranes could again be at risk — either from crashing into the towering wind turbines and transmission lines or because of habitat lost to the wind farms. “Basically you can overlay the strongest, best areas for wind turbine development with the whooping crane migration corridor,” said Tom Stehn, whooping crane coordinator for the U.S. Fish and Wildlife Service.”
Wind power has stopped running in Australia because authorities were concerned at the number of birds dieing each year from flying into wind turbines. The influence that birds have on the wind industry is fairly large if you think about it.
Wind turbine towers have lights on them. This can create problems for migratory birds, which rely on the stars to guide them, and which aren’t evolved to interpret unnatural lights coming from the ground at night.
If wind does not harm the environment, then harnessing the energy of the wind should not be a problem to the environment.
Due to the high spinning-speed of wind turbines, a substantial amount of lubricant is required. This lubricant leaks from the turbine and gear box and often is cast off of the tips of the spinning turbine blades into the surrounding ecosystem. This can kill plants and wildlife and can drain into local water supplies.
The reverberations of offshore wind turbines in the water can disturb marine wildlife and disorient them.
While the installation costs of windmills can be high, the running costs are relatively low. Owners can set up windmills and effectively forget about them.
“wind farms can be built piecemeal, unlike most power stations. A half-finished coal-fired or nuclear power plant is a useless waste of money, but a half-finished wind farm is simply a wind farm half the size originally intended—and one that has been providing revenue since the first turbine was completed.”
“[Wind energy is a] very good way of hedging against volatile oil prices and potentially volatile carbon costs.”
Wind is naturally occurring and cannot be exhausted. This compares favorably to exhaustible resources such as oil, coal, and gas.
There is more wind energy in the world than man could ever need to fulfill its energy requirements. In Britain, for instance, three times the wind energy used by the UK blows over the surface of the country.
Wind energy is entirely free. This compares with favorably against almost all other forms of electricity generation, in which the fuel costs money (nuclear, coal, oil, gas…).
Unlike many other forms of fuel for electricity generation, wind “fuel” does not need to be transported to the windmill generator. It flows, instead, directly to the generator.
Wind energy is, compared to other sources of energy, very young. It is advancing, therefore – in terms of the technology, manufacturing processes, and supporting industries – at a relatively fast pace.
Unlike many other forms of energy generation, wind generators do not require the cycling of water for cooling or as the medium for transferring heat energy into usable electric energy (such as with coal or gas).
Installation cost. Putting in a windmill costs about $45000 to $50000.
“Sweden’s gleaming wind park is entering service at a time when wind energy is coming under sharper scrutiny, not just from hostile neighbors, who complain that the towers are a blot on the landscape, but from energy experts who question its reliability as a source of power.
For starters, the wind does not blow all the time. When it does, it does not necessarily do so during periods of high demand for electricity. That makes wind a shaky replacement for more dependable, if polluting, energy sources like oil, coal and natural gas.”
“to capture the best breezes, wind farms are often built far from where the demand for electricity is highest. The power they generate must then be carried over long distances on high-voltage lines, which in Germany and other countries are strained and prone to breakdowns. In the United States, one of the areas most suited for wind turbines is the central part of the country, stretching from Texas through the northern Great Plains — far from the coastal population centers that need the most electricity.”
Wind turbines are fully exposed to wind, rain, snow, and variable temperatures, all of which wear on the windmills. Repairs of windmills, therefore, are commonly required, and the eventual replacement of operating windmills can be expected.
Because wind blows inconsistently, wind turbines and generators are constantly ramped up and down. This is mechanically stressful for wind turbines and increases maintenance and failure rates.
Placing windmills on a ridge is often a subject of controversy in communities. There is a threat of litigation, therefore, that accompanies the installation of windmills that can be costly and even result in the forced removal of windmills from land.
4 Wind energy is unpredictable and must be “backed up” by conventional generation. No power plant is 100% reliable. During a power plant outage—whether a conventional plant or a wind plant—backup is provided by the entire interconnected utility system. The system operating strategy strives to make best use of all elements of the overall system, taking into account the operating characteristics of each generating unit and planning for contingencies such as plant or transmission line outages. The utility system is also designed to accommodate load fluctuations, which occur continuously. This feature also facilitates accommodation of wind plant output fluctuations. In Denmark, Northern Germany, and parts of Spain, wind supplies 20% to 40% of electric loads without sacrificing reliability. When wind is added to a utility system, no new backup is required to maintain system reliability
In Denmark, which pioneered wind energy in Europe, construction of wind farms has stagnated in recent years. The Danes export much of their wind-generated electricity to Norway and Sweden because it comes in unpredictable surges that often outstrip demand.
In 2003, Ireland put a moratorium on connecting wind farms to its electricity grid because of the strains that power surges were putting on the network; it has since begun connecting them again.
Electricity grids are typically designed to have a hand full of very large generators contributing massive quantities of energy to the grid from very few locations. Wind energy runs contrary to this model, with many windfarms theoretically contributing small quantities of electricity to the grid from widespread locations. This runs contrary to the original model of grid design, and grids may have a difficult time dealing with it.
“Wind energy requires a production tax credit (PTC) to achieve these economics. True, but every energy source receives significant federal subsidies; it is disingenuous to expect wind energy to compete in the marketplace without the incentives enjoyed by established technologies.”
“Creating a welfare-dependent industry in the province may benefit the backers of these projects, but the potential cost to taxpayers is huge, and the outlook for an unsubsidized industry is grim. …The wind power industry in Canada gets a federal government subsidy of $10 per megawatt hour. But B.C. consumers can expect to dig deeper. The cost of electricity from wind power is about $71 per megawatt hour. That compares to about $48 for natural gas and $25 for electricity produced from B.C.’s heritage hydro assets.”
As a result, natural wilderness or crop and livestock farming can continue around the bases of the turbines.
Wind energy is diffuse, so requires collection over wide swaths of territory. This is inefficient and economical costly, and puts pressure on protected environmental areas.
By increasing the demand for land, wind energy creates an incentive to clear forests and other natural areas to make way for wind turbines.