Wind energy is on the rise as a clean renewable form of energy. It has many advantages – no carbon emissions (beyond construction of the turbines themselves), no pollution, no waste, and no use of limited resources. The three often-cited downsides of wind power are that the turbines can be an eyesore, they may cause symptoms in susceptible individuals (so-called wind turbine syndrome, WTS), and they can be a hazard to flying creatures.

The eyesore issue for me is not a big issue. I actually think wind turbines dotting the horizon look pretty, but even if you disagree that is a small price to pay for the advantages.

I’m a bird watcher, and so am very sensitive to the issue of protecting bird diversity. I wrote about this issue previously.

A review of scientific studies of the number of bird deaths caused by wind turbines estimates that  140,000 and 328,000 bird deaths are caused each year. This may seem like a lot, but a study published in 2013 concluded that domestic cats kill between 1.3 and 4.0 billion birds each year. Further, an estimated 100 million birds are killed each year by flying into windows.

This makes the number of birds killed by wind turbines a round-off error.

Wind turbines may, however, pose more of a threat to bats. Estimates are between 600,000 to 900,000 bat deaths per year from wind turbines.  This may be because bats evolved behaviors to follow wind currents to find food and mates, and turbines reproduce those currents, luring bats to their deaths.

This is a solvable problem, however. Scientists are studying how to place wind turbines, and perhaps other techniques, to limit their threat to flying creatures.

Wind Turbine Syndrome

The main bone of contention with wind turbines is so-called wind turbine syndrome, the belief that living near wind turbines can cause a host of symptoms, including headaches, dizziness, nausea, and disturbed sleep.

This issue is in the news again because of an article in the Huffington Post which points out that Wisconsin Governor Scott Walker’s includes $250,000 to study the health effect of wind turbines.

The question raised is this – is it reasonable to fund further research into alleged WTS or is this just a tactic to deny existing evidence and keep wind energy down? I think both may be simultaneously true.

There is a strong case to be made for WTS being largely psychological. Symptoms correlate best with those who find wind turbines annoying, or consider them eyesores, and who do not benefit from them financially. The symptoms are those that are commonly caused by nocebo effects, or psychological effects.

The question remains, however, do nocebo effects explain some or all of WTS complaints?

The other position is that wind turbines can affect the vestibular system and possible trigger migraines or migraine-like symptoms in some individuals. Migraines can be triggered by subtle effects such as variations in barometric pressure. Sufferers will sometimes have headaches triggered by storm fronts or jet travel, for example.

A 2013 review concluded that there is some evidence that infrasound (sound of too low a frequency to hear) can affect the vestibular system, and so WTS is at least plausible.

A 2014 systematic review of possible WTS concluded:

Exposure to wind turbines does seem to increase the risk of annoyance and self-reported sleep disturbance in a dose-response relationship. There appears, though, to be a tolerable level of around LAeq of 35 dB. Of the many other claimed health effects of wind turbine noise exposure reported in the literature, however, no conclusive evidence could be found. Future studies should focus on investigations aimed at objectively demonstrating whether or not measureable health-related outcomes can be proven to fluctuate depending on exposure to wind turbines.

A 2015 review concluded:

In conclusion, there is some evidence that exposure to wind turbine noise is associated with increased odds of annoyance and sleep problems. Individual attitudes could influence the type of response to noise from wind turbines. Experimental and observational studies investigating the relationship betweenwind turbine noise and health are warranted.

I know it is common for studies to conclude that more research is necessary, but these conclusions seems reasonable given the evidence. The consensus seems to be that it is possible there is an effect here, but it is limited and is still compatible with a nocebo effect, although a physiological effect in some people cannot be entirely ruled out.

So – it seems that it is not justified to cite current evidence as being against the use of wind turbines, but at the same time there is room for further research. The question regarding Scott Walker is this, will the funded research be objective and address the proper questions?

Conclusion

Overall, wind turbine energy is a great source of clean energy. No source of energy is free from downsides, and so citing possible problems in isolation as an argument against any particular source of energy is not valid, in my opinion. All such arguments need to be framed in terms of relative risk and cost compared to other sources of energy.

The possible health effects of wind turbines are controversial and minor. This is not to minimize the quality of life effects this can have on a person with symptoms, but we are not talking about a risk of cancer or death.

The possible risks of wind energy need to be compared to the known risk of burning fossil fuels. The air pollution from burning coal and gas kills an estimated 40,000 people a year in the UK and similar numbers in the US. That dwarfs any health issues from wind turbines, even if they are physiological.

Further, the possibility of WTS seems like an entirely solvable problem, mostly involving the placement of wind turbines with respect to residential areas. Advances in wind turbine design may also help.

A quarter of a million dollars to study possible WTS seems entirely reasonable, as long as it is used properly.

This seems like one area where we should be able to follow the scientific evidence rather than ideology, but I know that is wishful thinking.