Nuclear power was first used to generate electricity in South Carolina at a small, 17 megawatt (MW = 1,000,000 watts) experimental prototype by South Carolina Electric and Gas (SCE&G) and partners at Parr from 1963 to 1967. Inspired by this and by the Atoms for Peace program of the federal government, in 1967 the General Assembly passed the Atomic Energy and Radiation Control Act (Act No. 223). A primary goal of the act was to attract new, high technology industry (nuclear and otherwise), with the legislation designating responsibility for promoting and developing “atomic energy resources” in South Carolina to the State Development Board. This led to the creation of nuclear-powered electrical generation plants and the creation of the Barnwell Low Level Radioactive Disposal site. The state had earlier experienced the benefits of a similar effort in the early 1950s with the creation of the Savannah River Site (SRS), which produced tritium and plutonium for nuclear weapons and also provided a repository for high-level radioactive waste.
Seven nuclear reactors, with a combined capacity of 6,525 MW, were in operation in South Carolina by 1986; the first one was generating electricity in 1970. By the start of the twenty-first century, more than half (52.2 percent) of the electricity generated in the state was created by nuclear fission, as compared to about 20 percent for the United States as a whole. Few other states can claim such a strong nuclear profile. In terms of the percentage of electricity needs generated with nuclear power, South Carolina is second only to Vermont. In terms of overall nuclear capacity, South Carolina trails only Pennsylvania and Illinois.
Replacing this nuclear production of electricity with coal-fired production would have required more than 22 million metric tons of coal. One gram of plutonium or uranium contains the energy of two tons of coal or one ton of oil. If uranium were replaced with coal, 277,000 tons of sulfur dioxide, 139,000 tons of nitrogen oxides, and 11,740,000 metric tons of carbon dioxide would have been released into the South Carolina atmosphere in 2000 alone.
All of the commercial nuclear reactors in South Carolina are pressurized water reactors. This means that the primary reactor coolant is maintained at a pressure that is high enough to prevent boiling in the reactor core. The core consists of roughly one hundred fuel modules, each of which is made up of a few hundred fuel rods. Inside each sealed fuel rod are cylindrical fuel pellets that contain uranium oxide in a ceramic matrix. The primary coolant carries the heat produced by fission of the uranium atoms to steam generators, where a separate, secondary water circuit is heated to produce steam. This steam is piped outside the primary containment room to turbine generators to produce electricity. As a result of this and the use of cooling water (a third water circuit), the steam is condensed into liq- uid water and returned to the steam generators. All of this resides inside a secondary containment barrier. These multiple barriers keep nearly all radiation from being released to the environment.
Some low-level radioactive waste (LLRW) is generated in the process of monitoring and maintaining the reactor plant and is buried in the Barnwell LLRW repository. The expended fuel modules are stored on site at the reactor plants, pending the opening of a federal high-level radioactive waste facility under Yucca Mountain, Nevada. South Carolinians are exposed to natural radioactivity that far exceeds what is released by these plants. Medical exposures are even higher. Nevertheless, nuclear power has been, and remains, a controversial subject in South Carolina and elsewhere. Critics cite environmental and safety concerns, especially regarding the storage of radioactive waste in South Carolina and in the wake of highly publicized accidents at nuclear power plants at Three Mile Island in Pennsylvania and at Chernobyl in the Soviet Union.
South Carolina Nuclear Waste Task Force. Report of the South Carolina Nuclear Waste Task Force. Vol. 1, Report of the Task Force, December 15, 1999. Columbia: South Carolina Nuclear Waste Task Force, 1999.