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Energy perspective: is hydroelectricity green? Are you thinking that air pollution will be reduced significantly once the United States switches to electric vehicles? Guess again.

Article Excerpt
Introduction

The current worldwide concern over energy is primarily related to imported oil, oil drilling and refining capacity, and transportation capacity. However, this concern has bolstered interest in a broader range of "green" energy technologies. Concern over the environment is well founded. The Environmental Protection Agency's Office of Air Quality Planning and Standards (1998) estimates that by 2010, electrical generators in the United States will dump 182,968 tons of particulate air pollution per year. These pollutants include mercury, lead, arsenic, hydrogen chloride, and many more carcinogens and toxins that cause lung cancer, asthma, and other diseases, and degrade flora and fauna. Also released is carbon dioxide, the primary greenhouse gas. Are you thinking that air pollution will be reduced significantly once the United States switches to electric vehicles? Guess again. There may be a reduction in air pollution in busy locations, but its significance remains to be seen. China uses coal extensively to generate electricity, and the United States also uses large quantities of coal for electrical power generation. In the future when your electric car runs out of electricity, you will plug it in to a convenience outlet at home, school, or work, and you will essentially be running your automobile on coal, natural gas, petroleum, or nuclear energy sources, all of which have major problems associated with them, and all of which are the main energy sources for generating electricity in the United States.

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Concern over imported energy in the United States is well founded. Some natural gas is imported, and natural gas accounts for 40 percent of the United States' electrical-generating capacity. Petroleum accounts for 6 percent of electrical-generating capacity. Coal and nuclear are major contributors to electrical generation also (Energy Information Administration, 2007). Coal accounts for almost all of the air pollution associated with electrical generation (Office of Air Quality Planning and Standards, 1998), and no one knows with great certainty how to safely store radioactive waste from nuclear power plants to the extent that humans and the environment will be protected one thousand years from now when that same waste will still be radioactive.

Could hydroelectricity be part of the solution?

Hydroelectricity

Hydroelectricity is similar to nuclear electricity in that there are very few airborne pollutants that result from the generating process during normal operation. Nuclear power accounts for slightly more of the United States' generating capacity than hydroelectric. There are currently 3,988 hydroelectric generating units in the United States--23.5 percent of all generating units. However, that only represents 7.7 percent of the electricity generated annually (Energy Information Administration, 2007). There is obviously a practical disadvantage to depending on hydroelectricity; these power plants are not always able to operate if the water supply is low.

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Why Fuels Are Needed to Generate Electricity

Electromagnetic induction is...

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