Friday, November 12, 2010
For one thing, it outweighs the need for a dependable and adequate source of electric power 24 hours a day. It also outweighs the need to get a handle on global warming and air pollution caused by human activity. We have an urgent need to decrease and, if possible, eliminate the use of fossil fuels for producing electric power. I agree with those who urge the development of solar power farms and wind power farms as sources of electric power to replace power plants that use coal, petroleum, or natural gas as fuel. Unfortunately, there are few places where the wind blows all the time and no place where the sun shines all the time. We need other sources of power to fill the gap when wind and sun can't supply our needs.
There are three sources of supplemental power that I know of: geothermal, hydroelectric, and nuclear. Geothermal power is available in places of present or past volcanic activity, such as Iceland, Hawaii, Yellowstone National Park, and California. The technology of converting heat from the earth to electrical energy is not fully developed. In theory one can bury a heat exchanger in a hot place and convert water to steam and run turbines. The development of materials for heat exchangers and means of placing such large objects deep underground have not advanced very far. More work needs to be done before we can hope to obtain a significant fraction of our power needs from the earth's heat.
Hydroelectric power has been used for a long time. The technology is mature. In addition, most of the available water power is already in use. We can not hope to make a significant addition to our power capability by building more dams with turbines. In fact, there is pressure to destroy some of the dams that we have constructed as a means of restoring runs of migratory fish, especially salmon.
The remaining source is nuclear power. I admit to a bias in favor of nuclear power, having studied nuclear physics in graduate school and having worked for companies involved in designing nuclear power reactors or economical means of concentrating the isotope U-235 in raw uranium. I recognize that a nuclear explosion is a dangerous thing. However, the experience with nuclear power has shown that there are fewer deaths and cases of illnesses per megawatt-year of energy produced by nuclear reactors than by fossil-fuel fired power plants, especially coal plants. In addition to adding to the burden of CO-2 in the atmosphere, coal-fired plants also spew compounds of sulfur, resulting in acid rain in regions down-wind from the plants, and also radioactive elements such as uranium that are present in trace amounts of coal. Before 1950 it was known that a coal plant would emit more radioactive material than a nuclear plant of the same power. Even then nuclear power was touted as "clean" power.
The argument that nuclear power is potentially dangerous has to be taken in context. Hydroelectric power is potentially dangerous. Dams break and drown people. Coal miners die in mine accidents. Geothermal power is obtained from dormant volcanoes which will, some day, become active. Windmills for power generation kill migrating birds. Solar farms have to be located in places where there is strong sunlight every day; most of those places are far from the centers of population where the power is needed. High-voltage transmission lines have to be built to deliver the power. High voltage wires can break and start fires and cause other damage. Nothing is inherently safe. Even abstention from the use of electrical power can cause death due to freezing.
I had an opportunity to sign a petition, but I passed it up.