Wind energy and the construction of wind turbines to produce electricity have been controversial on several levels. Is it practical? Is it economical? How does it affect the environment? Does it really work? Is it reliable? Can it compete with coal and natural gas and hydro? There has been a lot of discussion on all these topics and not many conclusions. My emphasis on this discussion will be directed at the environmental effects.
Let’s start with a few wind energy facts. Windmills have been in use since 2,000 B.C. and were first developed in China and Persia. Wind power is currently the fastest-growing new source of electricity production in the world. A single wind turbine can power 500 homes. There’s enough on-shore wind in America to power the country 10 times over. Around 80 different countries use wind power to generate electricity commercially (as of 2009). In 1997, wind power generated only 0.1 percent of the world’s electricity, this increased to 1.5 percent in 2008 and 2.5 percent in 2010. In some countries such as Denmark and Portugal, wind power contributes around 20 percent of the total electricity production. These facts come from The Wind Energy Foundation.
Wind power technology is a mainstream method of electricity generation. It has several positive environmental impacts and a few negative impacts. Probably the most positive environmental impact is reduced greenhouse gas emissions. Electricity generation is the largest industrial source of air pollution in the United States. The United States produces six billion metric tons of carbon dioxide (CO2) annually. Forty percent of CO2 emissions are generated by the electric power sector. That is 2.4 billion metric tons. Wind power generates no emissions. If one megawatt-hour of wind energy was used instead of coal energy, there would be a reduction of 1,200 pounds of CO2 emissions.
Reduced water usage would be a second positive impact. Power plants require cooling water. In 2005, U.S. coal, nuclear, and natural gas plants used more than 100 billion gallons of fresh water per day. This is more than agricultural irrigation, municipal water supplies, and household use combined. These power plant cooling systems also draw in and kill billions of fish per year and harm other marine life when the cooling water is returned to waterways at dangerously high temperatures. Wind power uses virtually no water. An increase in wind power produced electricity could be a benefit, especially in years of drought.
Wind turbines do not emit air pollutants. The National Academy of Sciences (NAS) has calculated that electricity generation in the U.S., mainly from coal plants, comes with a hidden cost of more than $60 billion annually in health damages from air pollution. This pollution includes emissions of sulfur dioxide, nitrogen oxides, and particulates, which combine to form smog. According to the NAS and the
American Lung Association, these pollutants place people at risk for decreased lung function, asthma, respiratory infection, lung inflammation, and aggravation of respiratory illness.
Coal plants have been linked to mercury pollution of water that becomes concentrated in fish, which can cause brain damage when ingested by young children and birth defects when ingested by women of child-bearing age. Some solid waste from coal plants contain heavy metals and other toxic substances that, if not disposed of properly, can contaminate drinking water supplies and harm local ecosystems.
So far I have painted a pretty rosy picture for wind power. There are some negatives to wind power. The biggest argument, environmentally, has been bird and bat collisions. There have been several studies done to try and verify the number of collisions with wind turbines. A USDA Forest Service study shows wind power causes fewer bird fatalities (approximately 108,000 a year) than buildings (550 million), power lines (130 million), cars (80 million), poisoning by pesticides (67 million), domestic cats (at least 10 million), and radio and cell towers (4.5 million). The NAS estimates wind power bird fatalities are about three of every 100,000.
Bat fatalities remain a concern. The wind power industry is working with agencies like The Bat and Wind Energy Cooperative and the American Wind Wildlife Institute in finding solutions for the bat. They have already found that feathering turbine blades during times of low wind speeds reduces bat deaths by more than half.
Even though commercial wind power and wind turbines are relatively new, the environmental effects seem to be relatively few. Obviously, there are a lot of other factors in making commercial wind power feasible. There is quite a bit of good, unbiased research out there now and a number of new studies being done on the pros and cons of wind power. Take the time and see what may be a significant future step in electricity generation.