Energy and the natural environment

The production and use of energy has more impact on the environment than any other single human activity. Wind power is seen as a solution to the environmental problems caused by nuclear, hydroelectric, natural gas, and coal power plants. Coal and natural gas power plants cause air pollution. Nuclear plants create dangerous radioactive waste.

Hydroelectric plants block rivers. Carbon dioxide emissions from fossil-fuel plants are a significant source of greenhouse gases, a leading cause of global climate change. Wisconsin gets 75 percent of its power from coal plants, which cause 48 million tons of greenhouse gas emissions (carbon dioxide), 206,000 tons of acid rain emissions (sulfur dioxide), and 107,000 tons of smog emissions (nitrogen oxides) each year.

The "green" energy solution to pollution

The production of electricity is responsible for a major portion of air pollution in America. According to the Environmental Protection Agency, electric generation causes:
• 64 percent of all emissions of sulfur dioxide (SO₂), the leading component of acid rain and fine particulates
• 40 percent of all man-made emissions of carbon dioxide (CO₂), the leading greenhouse gas believed to contribute to global warming
• 26 percent of all emissions of nitrogen oxides (NOx), a key component of ozone (smog), acid rain, and fine particulates

In addition, power plants have been identified as a source of heavy metal emissions, such as mercury, which can contaminate lakes and rivers. These emissions can affect human health; and damage crops, buildings and monuments. They can also reduce visibility in scenic areas and harm wildlife habitat.

The main alternatives to fossil fuels currently in place are nuclear power and large-scale hydroelectric power. Nuclear power creates highly radioactive waste, which must be carefully stored for thousands of years. Large hydroelectric dams have blocked rivers, preventing the migration of fish and decimating their populations in some regions.

What about the birds?

In some locations, primarily the Altamont Pass in California, wind turbines have affected bird populations. East of Oakland, California, the windy Altamont Pass is a popular feeding spot for birds of prey, as well as home to 7,000 wind turbines. In 1992, a study of bird mortality at the Altamont Pass found 182 dead birds over a two-year period, including 119 birds of prey (raptors). About half of the raptor deaths were attributed to collisions with the wind turbines.

After extensive studies it was determined that the leading causes of the bird kills were the lattice towers (that look much like the Eiffel Tower), which allowed the birds to perch, and the high rotational speed of the blades. Since the release of these studies the wind turbine industry has largely eliminated the use of lattice towers and significantly reduced the speed of the rotating blades, each of which has significantly reduced avian mortality.

In Wisconsin (and the Midwest in general) wind turbines seem to have a smaller effect on bird populations than those in more mountainous regions like the Altamont Pass. The landscape is relatively flat, there are no narrow flyways, and birds can maneuver around or over the turbines with relative ease. Indeed, in five years of research, wind turbines in the Midwest have not been found to cause any impact on bird populations.

Energy and the human environment

What about the noise? Some people are concerned about the noise of wind turbines. A modern wind turbine will produce about 50 decibels of noise at a distance of about 300-600 feet—primarily a rhythmic "whooshing" sound from the blades. This is comparable to the sound of light traffic at a distance of 100 feet, or the typical sounds of a private business office. The effect of the sound will vary depending on distance from the turbine, wind speed and direction, the amount of background noise, and the time of day.

With smaller and older wind turbines, generator vibrations can be more prominent, making a sound like a washing machine. However, even low levels of noise from wind turbines can be annoying to neighbors, especially at night when background sounds drop off. This generally affects people only during the summer when windows are open at night, and the home happens to be downwind from the turbines.

Aesthetic issues are harder to discuss, since they vary widely from one person to the next and are affected by emotional factors. Some people consider wind turbines to be an eyesore, while others consider them to be beautiful, while still others simply don't pay much attention to them.

How much land? Wind turbines each require about a half-acre of land. This includes land for the turbine and any access roads. As a result, turbines fit well onto agricultural land because farmers can still farm, simply making way for the turbine's base. Large turbines must be about five acres apart in order to avoid blocking each other's wind and causing turbulence. All of the land in between the turbines is available for crops and grazing sheep.

On a local basis as well as statewide, wind energy provides economic benefits. (CONTINUE)