We need more electricity. By 2050, many motor vehicles may be powered by batteries, putting extra strain on power generation capacity. Energy expert David MacKay of Cambridge University calculates that by 2050 the demand for electricity will be threefold its current level.

The burning of fossil fuels is widely believed to be partly responsible for global warming, and recent events in Japan have made nuclear power considerably less attractive. Wind farms have neither of these problems.

Electricity is produced by the wind in an environmentally-friendly manner: turbines produce no radioactive or chemical emissions, and the ground around turbines can still be employed for agricultural purposes. When turbines are dismantled, no damage to the environment results.

Wind farms can be costly to maintain, making electricity thus produced more expensive than by other means. They last for only 25 years. Some argue that the money would be better spent on energy conservation.

In this article I explore the question: are wind farms a good idea?

Farmers in the central Indian state of Maharashtra forced a public inquiry after claiming that the 1,700 wind turbines of the region had contributed to drought by diverting the monsoon rains. Protestors attempted to sabotage turbines. The theory goes that turbines draw in clouds and then fragment them, which industry experts describe as “bunkum.” It has been suggested that the protests owed more to local politics than science. The British Wind Energy Association said that research had shown rainfall to increase marginally downwind of tall buildings: deriving energy from wind increases precipitation.

In the United Kingdom, the Ministry of Defence is one of the foremost objectors to wind power projects, because they produce radar clutter. Headlines such as “Wind farms ‘a Threat to National Security’” have ensued. Wind farms can appear as storms on Doppler radar if positioned too close. A false warning of a tornado was issued in Kansas by a computer only to be canceled by a meteorologist. A tornado that was ignored because it was thought to be a wind turbine would be worse.

Engineers are labouring to filter turbines from radar in the same way as office blocks. Other solutions are to deactivate wind turbines during poor weather, use radar absorbent construction materials, position wind farms more carefully, and reshape turbines to deflect radar. More modern radar units are better able to handle the noise.

Flicker is the visual effect of rotating turbine blades, which has been feared to negatively impact people with migraines or epilepsy.. A British governmental study found no health risk.

Some complain that wind farms reduce the prices of houses as do transmission lines and cellphone towers, but in the United States an extensive 2009 study by the Renewable Energy Policy Project called The Effect of Wind Development on Local Property Values found that property prices rose. The report used actual house prices, rather than the opinions of experts or homeowners, as others have done. Another study by British estate agents found the same.

One of the strongest objections to wind farms has been their visual impact. The isolated, windy places where they are sited can be areas of outstanding natural beauty. The towers can be up to 262 feet high, but some people like them and have names for them and get to know their maintenance schedules. While they block light, they are perhaps preferable to buildings and traffic jams.

The activity of wind farms is, of course, variable. A survey of more than 20 British wind farms found them operating at 21 percent of their capacity. The worst culprit yielded only 7.9 percent of the amount it was capable of producing, and while it was old and small, newer sites also fared badly. The survey was carried out on behalf of the Campaign to Limit Onshore Wind Farm Developments, the omission of which detail from newspaper reports led Renewable UK to consider a formal complaint to the United Kingdom’s press-governing body. It was, they said, akin to not mentioning that a survey finding most people were opposed to nuclear power was initiated by Greenpeace.

The best performing wind farms deliver load factors in excess of 50 percent, putting them on a par with nuclear power. Carbon dioxide is a greenhouse gas. Electricity generated by coal has a cost of 32 ounces of carbon dioxide per kilowatt hour and electricity produced by gas costs half that, but electricity produced by the wind costs only 0.18 ounces per kWh.

Opponents claim that wind farms affect birds through disturbance, habitat loss, or collision. One British tabloid newspaper said they “shred flocks of birds as effectively as aircraft jet engines.” The argument came to prominence in the United Kingdom when a red kite, amongst the rarest birds in the country, was found dead in the vicinity of a wind farm and an autopsy determined that its injuries would have been expected to result from being cut by the blades of a wind turbine. According to the protest group Country Guardian, turbines have “killed birds in large numbers,” which was certainly the case at the Altamont Pass in California and Navarra and Tarifa in Spain.

The British Royal Society for the Protection of Birds (RSPB) approves of wind farms so long as they are wisely sited. Developers in the named areas failed to take account of wildlife, but problems can be avoided if wind farms are sited away from major migration routes and breeding, roosting, and foraging areas of species which are at risk. In the United Kingdom, the RSPB evaluates the likely impact of wind farms applications on bird populations at the application stage. The organization had previously opposed wind farms, and led a campaign to prevent the construction of one.

Birds are much more likely to meet their maker at the hands of cats rather than wind turbines: the American Bird Conservancy estimated that as many as 500 million birds are killed by cats each year, while the U.S. Fish and Wildlife Service said 440,000 are killed by wind turbines. Logically, cats should be eliminated before wind farms. Let us rid ourselves of these evil predators! Kill them all!

Bats are another matter. A surprisingly high number of bat carcasses have been found at wind farms in Europe and North America. In the United States, two species, the eastern red bat and hoary bat, accounted for more than 60 percent of the 2,500 deaths recorded. The problem is that the pressure surrounding a turbine blade is lower than normal, and the lungs of a bat entering the low pressure zone suddenly expand, bursting capillaries, which releases blood. Bats live a relatively long time and generate small numbers of offspring, and a long period of time would be required to recover from a large-scale loss. One possible solution could be to use radar to scare bats away.

A survey by the British homebuilder, Alliance and Leicester, found that peace and quiet was the one most critical factor for people contemplating the purchase of a house. One in five potential homebuyers rated it as the most important consideration, and people who object to wind farms are often motivated by that unending swish-swish-swish.

Wind farms, in fact, generate more complaints than the same amount of noise from another source. Pedersen and Persson Waye conducted a study, after which Pederson told a conference on wind farm noise in Berlin that the respondents considered the noise of rotor blades to be an intrusion into their private domain. The feeling of violation sometimes produced tiredness, unease, or even anger.

Anecdotal evidence opposing wind farms is powerful. The owner of a small cottage said, “The noise from just one turbine is sometimes unbearable… In the summer, sometimes it’s impossible for us to sit outside in our garden. When we’re inside, is isn’t possible to leave windows open because the pulsing noise is so intrusive.”

A letter to a local newspaper said, “I’m an green as the next guy and the developers promised there would be hardly any disturbance, but once they <wind farms> started operating I couldn’t stand to work in my garden – the noise was so awful, like someone mixing cement in the sky.”

Another said, “Things are at their worst at night if I want to sleep and there’s a strong wind coming from the turbines. They just drone on, making a ‘wooh wooh’ sort of sound. It’s ghostly. It’s like torture and would make anyone insane.”

But while anecdotes support opposition to wind farms, surveys do not. A survey commissioned by the British Wind Energy Association in 1994 studied 250 people residing near the 12 turbine wind farm of Kirkby Moor, six months after it commenced operation. 83 percent said they were “not at all concerned” or “not very concerned” about the noise. Similar findings were obtained by a major study in the early 1990s partly financed by the European Union (then the European Community) and another conducted by MORI on behalf of the Scottish Executive in 2003.

It is likely that more people would regard wind farm noise negatively in an area of low, natural background noise. A survey in the United States by Fidell found that people in wilderness area were highly annoyed by aircraft noise seven decibels lower than would be expected in a built-up area.

Dr. Nina Pierpont, a leading pediatrician in New York, has claimed that wind farms cause headache, balance problems, concentration and memory problems, tachycardia, sleep deprivation, migraines, panic attacks, visual blurring, vertigo, nausea, tinnitus, heart disease, irritability and a sensation of “internal quivering.” Nightmares and harm to cognitive development can, she say, occur in children. She studied people residing near wind turbines in the United States, the United Kingdom, Canada, Ireland, and Italy for more than five years. She is not affiliated with any organization and funded the research herself.

She calls the effect “wind turbine syndrome,” and posits that it results from disruption to the inner ear’s vestibular system by ultrasound or low frequency noise: the noise is heard through the bones. Amphibians can be adversely affected by this, and similarities between humans and fish were discovered by scientists at universities in Manchester in the United Kingdom and New South Wales in Australia in 2008. Dr. Pierpont’s findings were peer reviewed, and approved of by Dr. Christopher Hanning, who founded the British Sleep Society. He praised her “strength of character and conviction” for committing what she says has been labeled “heresy.” Professor Lord May, former chief scientific adviser to the British government, described Pierpont’s work as “impressive, interesting, and important.”

Pierpont examined 10 families from around the world who lived near extensive wind farms, a sample of 38 people who ranged from infants to septuagenarians. Eight of the families have since moved house.

Pierpont says her claims have been described as “imaginary” and that the wind industry will attempt to discredit and disparage her, much as the tobacco industry initially dealt with the health issues of smoking. She recommends that wind farms be no less than 1.2 miles from human habitations.

One heartrending supporting anecdote is that of a retired 53 year-old woman, who described what she heard as “like an airplane that never arrives.” She said her husband developed pneumonia shortly after nearby turbines became operational, having never previously had chest problems. She complained of constant ear nuisance and headaches and raised blood pressure. Other family members were also affected.

Governments and wind companies have always maintained that after 20 years of wind power, there have been no health risks linked to the noise and vibration of turbines. Acoustic engineers have found no risk to human health, and the position was endorsed by recent studies by a university. The British Wind Energy Association said that visitors to wind farms usually comment at their surprise at the quietness of turbines.

Pierpont’s study has been criticized for its small sample and insufficient control: many participants were already wholly convinced that wind turbines caused their problems. Many of the participants had pre-existing morbidities of mental disorder, migraine, hearing problems, motion sensitivity, or had previously been exposed to significant noise through work.

It is conceivable that problems might arise: Portuguese doctors studied the effects experienced by personnel flying at high altitudes and supersonic speed, and found that the rare illness of vibroacoustic disorder might result. With this condition, the structure of internal organs such as the lungs or heart is altered by vibration.

A study led by University of Illinois professor of atmospheric sciences, Somnath Baidya, Roy found that the area around turbines was marginally cooler in daytime and marginally warmer at night. This could result from mixing of warm and cool air by turbine rotors. Many wind farms are located on farmland and the effect could offer some degree of frost protection and could possibly extend the growing season.

The teetering of nuclear reactors at Fukushima Daiichi close to meltdown has diminished the attraction of nuclear power to Germany and China, which suspended nuclear projects. Wind farms withstood the Japanese disasters rather better than nuclear power plants. No members of the Japan Wind Power Association reported damage, even the Kamisy semi-offshore wind farm 186 miles from the epicenter of the earthquake. Operators have been asked by electricity companies to increase activity.

As for coal, in 2008 Kansas became the first state to reject the building of further coal-fired power plants because of their effect on global warming. Governor Kathleen Sebelius recommended wind energy in their place.

Improvements to technology could make wind power yet more enticing. Wind speed is greater at high altitude, especially in the sub-tropical and polar front jetstreams of 30 and 60 degrees latitude respectively. A turbine at great height could generate far more power, being active for 80 percent of the time in contrast to the 30 percent of ground-based facilities. It has been estimated that capturing only one percent of the energy of these winds would satisfy the electricity needs of the whole planet. Professor Bryan Roberts has worked on such a device since 1979. A Flying Electricity Generator (FEG) would resemble a helicopter in that the spinning blades would keep it airborne. It is estimated that 43 arrays of 600 FEGs could produce enough electricity for the whole of the United States.

At present, the capacity of the largest turbines is 5-6 MW, but more than 120 scientists at the European UpWind project have presented designs for turbines of 20 MW. One turbine of this type in the North Sea could generate enough electricity for 15,000 to 20,000 dwellings at a cost 15-20 percent higher than for today’s wind turbines.

A story whose teller insisted it was true told of a small, Midwestern college which wished to erect a wind turbine on campus. The school was atop a hill in the middle of a prairie, and the wind would have produced more than three quarters of the electricity the institution required. The strongest opposition came from a farmer who believed the appearance and noise of the wind turbine would lower property values. The man was a pig farmer (for city dwellers, large pig firms are generally odious and unsightly and tend to lower property values).

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