Ann de Rouffignac, OGJ Online Editor
Nuclear power proponents are looking to so-called “pebble bed” reactors as an alternative to existing nuclear plant design. Conventional power plants, which took up to a decade to build, use nuclear fuel rods clad in metal cooled by water. Pebble bed reactors can be built cheaply in less than three years, say proponents of the technology.
Pebble bed development work is under way in South Africa and at the Massachusetts Institute of Technology (MIT). Developers estimate total production costs competitive with natural gas-fired power plants. The technology employs nuclear fuel in graphite-coated spheres (about the size of tennis balls) cooled by an inert gas instead of water. About 400,000 fuel balls lie within a graphite-lined silo that is 30 ft high and 10 ft in diameter. Meltdown of the core is impossible, according to developers.
Eskom, a South African utility, and Philadelphia-based Exelon Corp. are developing a reactor design they say can be manufactured in 100 MW modules, tiny by most nuclear plant standards.
Exelon has invested $7.5 million for a 12.5 percent equity stake in the design development.
Ann de Rouffignac is senior electricity writer for PennWell’s Oil & Gas Journal Online.