Alternate Forms of Energy
With the rapid depletion of fossil fuels, oil and natural gas in particular, and with their environmental hazards such as global warming, air pollution and acid rain, it is clear that we need to develop alternate forms of energy. Below I discuss several alternatives as well as their merits and drawbacks.
Renewable Sources
Hydroelectric Power
Hydroelectric power has been in use for a long time; the first hydroelectric plant was built
in Rothbury, England in 1870. Today, hydroelectric power supplies 20% of the world's power
and it is estimated that it is capable of providing 9 to 12 times as much energy as it
currently does. However, there are environmental concerns regarding building new dams.
Solar Power
Solar power is a potentially very attractive form of energy, since it is plentiful and
pollution-free. Just one tenth of a percent of the earth's surface potentially suffices to
produce our current power needs. Nevertheless, there are several disadvantanges to solar
power. Solar cells are only operable during the daytime when the sun is shining, and
currently have an efficiency of only 7-18 percent. In order to be useful all the time, solar
power must first be converted to another form of energy.
Wind Power
Wind power has been in use the longest of all renewable sources; the first use
was in Persia around 200 BC for grinding grain. It currently accounts for less than 1%
of worldwide energy use, though its use is growing quite fast. It is estimated that wind
power can potentially produce about 5 times the world's current energy use.
Geothermal Power
Geothermal power is currently a rather limited renewable resource. Tidal power, one source
of geothermal power, can potentially produce just one-quarter of the world's current power
needs. The heat from the earth is plentiful, but most of it is not currently available.
Bioenergy
Bioenergy, including biomass, biofuel, and biogas, is a fairly new source of energy.
Ethanol, a biofuel, was used by the Ford Model T from 1903 to 1926, until petroleum fuels
became cheaper. Since the first energy crisis in 1973, there has been renewed interest in
biofuels and other forms of bioenergy.
Non-Renewable Sources
Nuclear Power
Nuclear power is a non-renewable energy source. There are two potential forms of nuclear
energy, fission and fusion, though no commercial fusion plants have yet been developed.
Nuclear plants have been in use since 1954 and today they provide 7% of the world's energy.
Nevertheless, nuclear power has several serious drawbacks. Nuclear power produces hazardous
radioactive waste, and no viable solution has yet been offered on what to do with it. Also,
there is serious potential risk of nuclear accidents, such as the meltdown at Chernobyl,
Ukraine (formerly the USSR) in 1986. Furthermore, the amount of available uranium fuel is
limited; it is estimated that available resources will last only 50 years at their current
rate of use. Fusion power promises to alleviate nearly all the hazards of fission, but there
are several obstacles in its development and it is estimated that it won't become
commercially available until around 2050.