A Path for Nuclear Power
A novel but tested technology, the pebble-bed reactor, can make fission energy safe.
Energy Economics 101
Nuclear power plants are expensive to build but relatively cheap to run. Current estimates for the capital costs of a nuclear plant run in the range of $5,000 to $6,000 per electrical kilowatt. By comparison, coal plant capital costs are about $2,000 per electrical kilowatt. High-efficiency, gas turbine combined cycle plant costs are in the $600 to $1,000 per electrical kilowatt range. Simple cycle gas turbine plant capital costs are as low as $300 to $700 per electrical kilowatt.
The Energy Information Administration’s Annual Energy Outlook for 2014 report provides more meaningful estimates of the averaged levelized costs for generating technologies to be brought online in 2018. (Levelized cost represents the per-kilowatt hour cost of building and operating a generating plant over an assumed financial life and duty cycle). The projected levelized cost for an advanced coal plant is 12.3 cents per kilowatt-hour, whereas that of advanced combined cycle gas turbine plant is 6.6 cents per kilowatt-hour. An advanced nuclear plant, such as the ones under construction at Vogtle, comes in between, at 10.8 cents per kilowatt-hour. Nuclear is competitive, then, and a future carbon tax on technologies that produce carbon dioxide pollution could make it even more so.
One major controversy with nuclear power is what happens to spent fuel when a plant is retired. A good example of a cradle-to-grave story of a nuclear power plant is the Connecticut Yankee plant, located along the Connecticut River. It went online in 1968, and over its service life of 28 years it produced over 110 billion kilowatt-hours of electricity from its uranium fuel. The plant was decommissioned from 1998 to 2007, with all structures removed from three to four feet below ground level. The site is now a fairly flat field, with a low mound where the reactor building sat.
Located on a hill above the plant site is the Independent Spent Fuel Storage Installation. It consists of 43 dry storage casks mounted on a concrete pad that is 30 meters long by 60 meters wide and a meter thick. Forty of the casks contain almost all of the fuel assemblies used over the life of the Connecticut Yankee plant; the other three contain reactor vessel parts. Each cask is a vertical concrete cylinder, about four meters in diameter and six meters high, containing a cylindrical steel canister with nine-centimeter-thick walls. The casks, which cost $1 million apiece to construct, are licensed for a 20-year storage time, but could last 40 to 60 years or longer.
In the future, a federal agency might take possession of the installation. If that happens, the casks might simply stay in place, considering the significant expense of moving them to a permanent storage site—if one is ever chosen. That might not be a popular decision politically, but financially the decommissioning process has been taken into account. The cost of maintaining the installation is about $3 million a year. All of the plant decommissioning and spent-fuel storage costs had been factored into electric rates paid by customers during the plant’s 28 years of operation.