Current Major Energy Alternatives
In 1999, 104 nuclear plants supplied 23% of the electricity generated in the US. Nuclear power is an attractive alternative to combustion because in a per unit comparison it releases 100,000 times more energy than burning coal. The catch is that nuclear fission comes at the cost of creating nuclear waste. This has two major drawbacks. First, storage of this waste involves transporting highly radioactive waste through major metropolitan areas by rail or truck and depositing it deep within mountains. Furthermore, from nuclear waste come the materials for creating nuclear weapons.
On the transportation side of things, expanding nuclear production would do little to reduce dependence on foreign oil as oil provides only 3% of power generation. In the future, many doubt that the US will create more plants until safer methods for waste disposal are found. Estimates put this date at 2020 before we may see new reactors (Environment 251).
Currently 2,100 hydroplants provide about 9% of our electricity. Although hydropower does not contribute directly to carbon emissions, there are other environmental effects. For example, by controlling a riverís flood cycle, dams prevent nutrient rich silt from being deposited on floodplains, resulting in decreased agricultural productivity downstream. Dams also effect habitats, fish migrations, and can displace communities. Dams also Ďsilt upí over time because the water on the upstream side of the dam drops its sediment load when it stops in the upstream reservoir. This sedimentation builds up over time, eventually filling the reservoir and ending the life of the dam.
During this decade, 500 dams are due to be re-licensed, ensuring that hydropower will continue into this century as a completely renewable resource.