Environmental Engineering Reference
In-Depth Information
Advocates of nuclear power claim that it is sustainable, reduces carbon dioxide emissions, and increases na-
tional energy security by decreasing the reliance on foreign crude oil. Supporters also argue that the risk of
storing nuclear radioactive waste is small and can be further reduced by advances in nuclear power plant tech-
nology. In addition, the overall safety record for nuclear power plants is better than that for traditional fossil-
fuel power plants.
Critics of new nuclear power plants believe that nuclear power is dangerous and not worth the cost or the risk.
These critics are generally skeptical that new technology can decrease the hazards of nuclear radioactive waste.
Critics also point out the problems of storing the nuclear waste, the lack of a national policy on nuclear storage,
the potential radioactive contamination by accidents or terrorism, and the long-term storage of the nuclear
waste before it is safe to be disposed of.
Nuclear Fission Process
Nuclear-power-generated electricity is usually produced by a process called nuclear fission. During the nuclear
fission reaction, shown below, an atom is split into two smaller elements along with by-products (neutrons,
photons, gamma rays, and beta and alpha particles). The fission reaction is exothermic, giving off great quant-
ities of heat. The heat is used to convert water into steam that turns a generator, which produces electricity.
This reaction must be carefully controlled to ensure that it does not critically overheat.
The potential energy per pound of nuclear fuel is exponentially greater than that of most established fuels
(coal, petroleum, and natural gas). However, it is impossible to create a nuclear fission reaction without produ-
cing radioactive waste, which remains highly radioactive for thousands or even millions of years. Currently,
most nuclear waste is stored on-site because there is no national program in the United States to dispose of
nuclear waste. By traditional standards, nuclear waste must be stored for the length of time it takes for the ma-
terial to go through ten half-lives. U-235, one of the most common nuclear fuels, has a half-life of 704 million
years, and U-238 has a half-life of about 4.47 billion years. In other words, nuclear waste must be stored
forever in a secure location.
