Domestic and international pressures are building rapidly on the United States to enact some form of legislation to curb greenhouse-gas emissions, as a spate of recent developments turns up the...
Tomorrow’s options for low-carbon baseload generation.
Harvard Business School Professor Joseph B. Lassiter III puts it bluntly: "The world has allowed nuclear to become virtually an orphaned technology." And that, he adds, despite nuclear's potential to address one of the biggest problems of our time - the need for climate-friendly energy. Lassiter identifies the culprit: "Right now we're letting the ends of the ideological spectrum and the entrenched power of legacy interests stalemate a path to the future." Blocking that path, he notes, are anti-nuclear politics, regulatory policy, and utility investment strategies.
Despite these barriers, however, nuclear power is seeing some resurgence in research and development. Next-generation nuclear technologies are attracting interest from investors with a long lead-time interest in innovative clean energy approaches. The challenge of climate change likely will necessitate a new wave of nuclear plant construction in the next 20 years. Investors naturally want a piece of that.
Over the course of many years, the biggest investors in advanced nuclear technologies have been taxpayers in America and other countries. Governments have funded substantial scientific research and engineering development toward the Generation IV (Gen IV) nuclear reactor. While nuclear plants always have offered power that's virtually free of GHG emissions, along with baseload generation at high availability factors, the new Gen IV concepts offer improvements over current-generation nuclear plants. These include the potential for lower capital costs and electricity prices, abundant fuel, fail-safe operation, dramatic reduction in volume of waste (and a much shorter decay life), and reduced risks of nuclear proliferation.
Lower capital costs for some Gen IV concepts come from improved fuel utilization and lower pressure requirements. Molten salt and sodium-cooled reactors operate at low pressures, and don't require expensive pressure vessels for containment. Where they use molten fuel, they don't require thousands of fuel rods, which are expensive to construct and to replace every four years, when the level of radiation renders them ineffective. The low-cost electricity prices stem from Gen IV technology's use of higher temperature coolants that increase thermal conversion efficiencies to the 45 percent range, where traditional power efficiencies are closer to 33 percent.
Potential fuels include uranium and thorium, but also the vast, inexpensive resources of the tailings from the current uranium enrichment process - and also, importantly, the U.S. inventory of spent nuclear fuel. Fuels are used efficiently, with the consumption of up to 96 percent of the fissionable material in some reactor designs. The broad and diversified sources of fuels mean that these models can supply worldwide power needs for centuries.
Additionally, some Gen IV concepts reduce or eliminate the potential of a hydrogen explosion, such as occurred at Fukushima.These offer fail-safe solutions, without the threat of massive release of radiation.
Gen IV around the World
In the past decade, worldwide adoption of Gen IV concepts to provide power has moved forward deliberately, starting with the