Energy and the Environment

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Energy and the environment

Energy is a prime factor in environmental quality. Extraction, processing, shipping, and combustion of coal , oil, and natural gas are the largest sources of air pollutants, thermal and chemical pollution of surface waters, accumulation of mine tailings and toxic ash, and land degradation caused by surface mining in the United States.

On the other hand, a cheap, inexhaustible source of energy would allow us people to eliminate or repair much of the environmental damage done already and to improve the quality of the environment in many ways. Often, the main barrier to reclaiming degraded land, cleaning up polluted water, destroying wastes, restoring damaged ecosystems, or remedying most other environmental problems is that solutions are expensiveand much of that expense is energy costs. Given a clean, sustainable, environmentally benign energy source, people could create a true utopia and extend its benefits to everyone.

Our ability to use external energy to do useful work is one of the main characteristics that distinguishes humans from other animals. Clearly, technological advances based on this ability have made our lives much more comfortable and convenient than that of our early ancestors. They have also allowed us to make bigger mistakes, faster than ever before. A large part of our current environmental crisis is that our ability to modify our environment has outpaced our capacity to use energy and technology wisely.

In the United States, fossil fuels supply about 85% of the commercial energy. This situation cannot continue for very long because the supplies of these fuels are limited and their environmental effects are unacceptable. Americans now get more than half of their oil from foreign sources at great economic and political costs. At current rates of use, known, economically extractable world supplies of oil and natural gas will probably last only a century or so. Reserves of coal are much larger, but coal is the dirtiest of all fuels. Its contribution of greenhouse gases that cause global warming are reason enough to curtail our coal use. In addition, coal burning is the largest single source in the United States of sulfur dioxide and nitrogen oxides (which cause respiratory health problems, ecosystem damage, and acid precipitation). Paradoxically, coal-burning power plants also release radioactivity , since radioactive minerals such as uranium and thorium are often present in low concentrations in coal deposits.

Nuclear power was once thought to be an attractive alternative to fossil fuels. Billed as "the clean energy alternative" and as an energy source "too cheap to bother metering," nuclear power was promoted in the 1960s as the energy source for the future. The disastrous consequences of accidents in nuclear plants, such as the explosion and fire at Chernobyl in the Ukraine in 1986, problems with releases of radioactive materials in mining and processing of fuels, and the inability to find a safe, acceptable permanent storage of nuclear waste have made nuclear power seem much less attractive in recent years. Between seventy and ninety percent of the citizens of most European and North American countries now regard nuclear power as unacceptable.

The United States Government once projected that 1,500 nuclear plants would be built. In 2002, only 105 plants were in operation and no new construction has been undertaken since 1975. Many of these aging plants are now reaching the end of their useful life. There will be enormous costs and technical difficulties in dismantling them and disposing of the radioactive debris. Some reactor designs are inherently safer than those now in operation, but public confidence in nuclear power technology is at such a low level that it seems unlikely that it will never supply much energy. Damming rivers to create hydroelectric power from spinning water turbines has the attraction of providing a low-cost, renewable, air pollution-free energy source. Only a few locations remain in the United States, however, where large hydroelectric projects are feasible. Many more sites are available in Canada, Brazil, India, and other countries, but the social and ecological effects of building large dams , flooding valuable river valleys, and eliminating free-flowing rivers are such that opposition is mounting to this energy source.

An example of the ecological and human damage done by large hydroelectric projects is seen in the James Bay region of Eastern Quebec. A series of huge dams and artificial lakes have flooded thousands of square miles of forest. Migration routes of caribou are disrupted, the habitat for game on which indigenous people depended is destroyed, and decaying vegetation has acidified waters, releasing mercury from the bedrock and raising mercury concentrations in fish to toxic levels. The hunting and gathering way of life of local Cree and Inuit people has probably been destroyed forever. This kind of tragedy has been repeated many times around the world by ill-conceived hydro projects.

There are several sustainable, environmentally benign energy sources that should be developed. Among these are wind power, biomass (burning renewable energy crops such as fast-growing trees or shrubs), small-scale hydropower (low head or run-of-the-river turbines), passive-solar space heating, active-solar water heaters, photovoltaic energy (direct conversion of sunlight to electricity), and ocean tidal or wave power . There may be unwanted environmental consequences of some of these sources as well, but they seem much better in aggregate than current energy sources. A big disadvantage is that most of these alternative energy sources are diffuse and not always available when or where we want to use energy.

We need ways to store and ship energy generated from these sources. There have been many suggestions that a breakthrough in battery technology could be on the horizon . Other possibilities include converting biomass into methane or methanol fuels or using electricity to generate hydrogen gas through electrolysis of water. These fuels would be easily storable, transportable, and used with current technology without great alterations of existing systems. It is estimated that some combination of these sustainable energy sources could supply all of American energy needs by utilizing only a small fraction (perhaps less than one percent) of United States land area. If means are available to move this energy efficiently, these energy farms could be in remote locations with little other value.

Clearly, the best way to protect the environment from damage associated with energy production is to use energy more efficiently. Many experts estimate that people could enjoy the same comfort and convenience but use only half as much energy if they practiced energy conservation using currently available technology. This would not require great sacrifices economically or in one's lifestyle.

See also Acid rain; Air pollution; Greenhouse effect; Photovoltaic cell; Solar energy; Thermal pollution; Wind energy

[William P. Cunningham Ph.D. ]



Davis, G. R. Energy for Planet Earth. New York: W. H. Freeman, 1991.


Weinberg, C. J., and R. H. Williams. "Energy from the Sun." Scientific American 263 (September 1990): 146-55.