Wind Power: Pros and Cons

There is no perfect energy source. Each and every one has its own advantages and compromises. This series will explore the pros and cons of various energy sources.  Learn about other forms of energy generation here.

When we think of wind power, we generally think of those large, high tech towers with slowly spinning blades that have sprung up in the past decade on hilltops in many areas of the country. But the fact is, wind is one of the oldest sources of power used by man. Our ancient ancestors used the wind to propel boats, grind grain and pump water.

While all of these applications still exist today, wind power is now primarily used to generate electricity at both the large and the small scale. Our discussion today will focus on large utility scale installations. In all cases, it is the kinetic energy, or movement of the air, that provides the mechanical power to perform the various forms of work.

According to a recent report posted by the DOE’s National Renewable Energy Lab (NREL), renewables can contribute 80% of American electricity by the year 2050. Much of it will be provided by wind power installations of this type.

Wind power has some obvious advantages: it’s clean and renewable and relatively cheap. While these advantages are largely global in nature (e.g. reduced greenhouse gas emissions and fossil fuel depletion), the disadvantages are primarily local (e.g. land use, noise and visual pollution). Of course, the main disadvantage of wind power is that the wind does not blow consistently or steadily.

Other issues have been raised, which have often been misconceptions. For example, one criticism is that windmills kill lots of wild birds. This was true of the early windmills, especially in the case of the wind farm located near Altamont Pass in California. Those turbines spun at high speeds and were located near a major avian thoroughfare. Today’s high efficiency turbines spin at lower speeds and use smooth poles to support the turbine instead of the lattice-style structures used earlier – which actually made nice bird nesting grounds.

Today, even the Audubon Society supports wind power, recognizing that global warming causing a far greater threat to the long term viability of bird populations than the occasional collision of a bird with a tower. The number of annual bird fatalities (around 20,000) is tiny when compared to transmission lines or cats.

Another controversy that has been brewing recently is the idea that windmills can cause global warming. This is another misconception.

Based on a study produced at the State University of NY (SUNY) at Albany, the ground around the turbines can warm up at night. This is due to the mixing, by the turbines, of the cool night air at ground level with the warmer air above. While the effect is real, the concern is not, since this phenomenon does not introduce new heat into the planet’s atmosphere, as the carbon dioxide layer does by trapping heat that would otherwise escape into space. Rather, this small, localized effect is simply mixing heat that is already there, with cooler air below it. If you think of it as a pot of soup on a stove, the sun provides the heat, the greenhouse gases form the lid, and the action of the windmills would be like you stirring the soup, albeit with a very small spoon. Life on Earth, as we know it today, evolved at temperatures that were present before the lid was on.

It is true that this mixing of air could impact local weather in the vicinity of the windmills, but experts believe that this effect can be reduced with enhanced turbine blade designs that minimize mixing and by siting the turbines in areas that are naturally more turbulent.

Here then are the wind power pros and cons.

Pros

  • Clean energy, no fuel to drill, frack, mine, transport or burn
  • Renewable and sustainable
  • Costs are relatively low and continue to decrease
  • Abundant domestic supply (16X current electric demand!)
  • The power is essentially free once the infrastructure is paid for.
  • Low life cycle carbon footprint. Breakeven in eight months.
  • Can be used almost anywhere.

 

Cons

  • As mentioned earlier, the wind is inconsistent, unsteady and unpredictable
  • Wind power is not cheap and like many energy sources, rely on government subsidies to remain competitive.
  • Wind farms are generally located in rural areas that might be otherwise picturesque. They are considered by some people to be an eyesore.
  • Some people complain of noise from the turbines.
  • Wildlife impact. Not only birds, but bats have experienced fatalities.
  • Localized impact on night-time temperatures and weather

At the end of 2011, the US had 46,919MW of installed wind capacity. This number is expected to grow rapidly, whether or not production tax credits (PTC) are renewed. There have been a number of recent mergers among wind developers as the industry consolidates.

In summary, wind power, is not a perfect solution, but it is far better than just about anything else we have available at the moment. I would consider it a good long term transitional energy source over the next fifty to a hundred years.

The other good thing about wind: unlike nuclear power, or tar sands oil, which will each leave a long term toxic legacy, when we are finally done with wind, we can simply take down the towers and allow nature to grow back in.

[Image credit: Wayfinder_73: Flickr Creative Commons]

What about other energy sources?

 

RP Siegel, PE, is the President of Rain Mountain LLC. He is also the co-author of the eco-thriller Vapor Trails, the first in a series covering the human side of various sustainability issues including energy, food, and water in an exciting and entertaining format. Now available on Kindle.

Follow RP Siegel on Twitter.

RP Siegel

RP Siegel, author and inventor, shines a powerful light on numerous environmental and technological topics. His publications include business and technical articles as well as books. His third, co-authored with Roger Saillant, is Vapor Trails, an adventure novel that shows climate change from a human perspective. RP is a professional engineer - a prolific inventor with 52 patents and President of Rain Mountain LLC a an independent product development group. He is also active in his community of Rochester, NY. A regular contributor to Mechanical Engineering magazine, RP recently returned from Abu Dhabi where he traveled as the winner to the 2015 Sustainability Week blogging competition.. Follow @RPSiegel on Twitter. Contact: bobolink52@gmail.com