Nuclear Energy - Power Plant Aging

Like other types of power plants, nuclear power plants have a lifespan after which they must be retired because the cost of running them becomes too high. The generation of nuclear power plants currently operating was designed to last about thirty years. Some plants showed serious levels of deterioration after as few as fifteen years. However, some have lasted well beyond thirty-year expectations. Whenever a power plant—whether coal, natural gas, or nuclear—is retired, it must be demolished and cleaned up so that the site can be used again.

Decommissioning Nuclear Power Plants

Eventually, the more than 400 nuclear plants now operating worldwide will need to be retired. There are three methods of retiring, or decommissioning, a reactor: safe enclosure (mothballing), entombment, and immediate dismantling.

Safe enclosure involves removing the fuel from the plant, monitoring any radioactive contamination (which is usually very low or nonexistent), and guarding the structure to prevent anyone from entering until eventual dismantling and decontamination activities occur. Entombment, which was used at Chernobyl, involves permanently encasing the structure in a long-lived material such as concrete. This procedure allows the radioactive material to remain safely on-site but at one location. Immediate dismantling involves decontaminating and tearing down the facility within a few months or years. This process is initially more expensive than the other options but removes the long-term costs of monitoring both the structure and the radiation levels. It also frees the site for other uses, including even the construction of another nuclear power plant. Nuclear power officials are also seeking alternative uses for nuclear shells, including the conversion of old nuclear plants to gas-fired plants.

Paying for the closing, decontamination, or dismantling of nuclear plants has become an issue of intense public debate. The early closing of several plants owing to safety concerns and poor economic performance has raised the question of how the costs of decommissioning can be covered. Industry reports contend that the cost of decommissioning retired plants and handling radioactive wastes will continue to escalate, causing serious financial problems for electric utilities. In addition to coal plants, new technologies, such as wind turbines and geothermal energy, are less expensive than nuclear energy plants when all factors are considered.