Source: Fotopedia
Image: phault
Wind energy as a power source is attractive as an alternative to fossil fuels because of its advantages:
1. The environmental effects of wind power are relatively minor
2. Wind power consumes no fuels and emits no air pollution
3. The energy consumed to manufacture and transport the materials used to build a wind power plant is equal to the new energy produced by the plant within a few months of operation
Source: Fotopedia
Image: dmarks007
Garrett Gross, a scientist from UMKC in Kansas City, Missouri explains that the impact made on the environment is minor when compared to the gained advantages. While a wind farm may cover a large area of land, many land uses, such as agriculture, are compatible. However, the wind turbines also pose some danger to birds and bats, which has been a concern in many locations. Some dismiss the number of birds killed by wind turbines as negligible when compared to the number that die as a result of other human activities, and especially the environmental impacts of using non-clean power sources. Others are in very strong disagreement with the placement of wind farms.
Source: Fotopedia
Image: USFWS Pacific Southwest Region
New evidence suggests that the critically endangered California Condor is being killed at the Tehachapi Pass wind farm in Southern California. In 1986 the world population was down to five birds resulting in one egg. Thanks to legislation allowing some to be raised in captivity, by 2008 the world population reached 327. As scavengers, they play a critical role in their food chain and ecosystem.
Source: Fotopedia
Image: Gilles San Martin
Bat species also appear to be at risk during key movement periods. Almost nothing is known about current populations of these species and the impact on bat numbers as a result of mortality at wind power locations. They roost under bridges, in culverts, trees, caves and even beneath clay roof tiles. Colonies vary in size from 20 to millions, so populations can prove difficult to calculate and monitor. The largest known California colony is close to 200,000 bats in a single cave. Recent studies indicate wind farms kill between 600,000 and 900,000 bats every year. However, bats prefer not to fly when it's windy. A 2010 study found that increasing and decreasing blade cut-in speeds could greatly reduce bat fatalities by 43-93% with minimal losses in power generation.
Source: Fotopedia
Image: Unhindered by Talent
Aesthetics have also been an issue in some areas. We, as urban planners, need to be particularly sensitive to large scale placements of wind turbines as the visual impact may create opposition from local communities. As an example, the Massachusetts Cape Wind project was delayed for years mainly because of aesthetic concerns. We also need to be sensitive to the pristine view which the commercial wind farm may irreversibly ruin.
Source: Fotopedia
Image: andjohan
Another solution may be placing the wind farms further from human, animal and bird activity. One solution may be to place them on the ocean, far enough from shore so migration birds and bats will not be affected and the view of the horizon will not be obstructed. Moreover, such a placement despite higher installation cost, is one of the greatest placements because water has less surface roughness than land (especially deeper water), and the average wind speed is usually considerably higher over the open water.
And how does that impact aquatic life? There is no perfect energy source. Each comes with its own set of advantages and disadvantages. It is up to us to take every aspect into consideration, weigh all the pros and cons and make informed decisions. Together we will learn.
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