By Kennedy Maize
Let us hope that the false hope of fast breeder reactors fueled with plutonium reprocessed from spent light water reactor fuel is finally properly interred. A new report from the same MIT crew that examined the future of nuclear power in 2003 buries the pipe dream of breeder reactors, or, at least, puts it in cold storage. Since Walter Zinn created EBR I in 1949, the rationale for breeders has been that uranium will be in short supply and costly, so something that creates more plutonium than it uses uranium will be necessary to keep nukes alive.
Breeders require reprocessing the spent fuel to recover the plutonium, an expensive, environmentally dangerous, and proliferation-prone technology that the U.S. correctly eschewed from the Ford administration through the Clinton administration, but which the George W. Bush administration sought to revive on an international scale. The Obama administration has largely backed away from the Bush policy.
The fundamental justification for fast breeders is flawed, says the report by MIT’s Energy Initiative, with a blue-ribbon advisory panel spanning the ideological spectrum from Jonathan Lash to John Sununu. The MIT study looks carefully at uranium supply and concludes that there is plenty U to go around for as far as anyone can reasonably see. The report – “The Future of the Nuclear Fuel Cycle” – comes not to praise reprocessing but to bury it. “For decades,” says the report, “the discussion about future nuclear fuel cycles has been dominated by the expectation that a closed fuel cycle based on plutonium startup of fast reactors would eventually be deployed. However, this expectation is rooted in an out-of-date understanding about uranium scarcity.”
The pursuit of fast breeders, in the U.S. and elsewhere, has been a heedless chase. Ernie Moniz, director of the MIT energy program and co-chairman of the study, said, “The failure to understand the extent of the uranium resource was a very big deal” for determining which fuel cycles were developed and the development schedule. Moniz, a physicist, is a former Department of Energy official in the Clinton administration.
With the historic assumption of limited uranium supply, the fast spectrum breeder had great appeal. Even then, enthusiasm for fast reactors glossed over the issues of scale and cost. An MIT press release accompanying the report says, “But it would take a conventional light-water reactor 30 years just to provide the plutonium to start one such breeder reactor and so far, such systems have not been found to be economically viable.”
Should the nation decide to make a change in direction in the ncuelar fuel cycle, the MIT report suggests examining enriched uranium-initiated breeders (with a unitary conversion rate). Either natural or depleted uranium could be added to the core at the same rate enriched uranium is burned up, and producing no excess nuclear material. This, says MIT, “is a much simple and more efficient self-sustaining fuel cycle.”
The major policy thrust of the MIT report is to keep on the LWR path for the next 100 years, while rigorously studying other approaches. A fuel cycle direction change, says the report, takes “50 to 100 years.” Charles Forsberg, MIT nuclear engineering researcher, said, “There has been very little research on the fuel cycle for about 30 years. People hadn’t gone back and looked at the underlying assumptions.”
“A key message from our work,” says the report, “is that we can and should preserve our options for fuel cycle choices by continuing with the open fuel cycle, implementing a system for managed LWR spent fuel storage, developing a geological repository, and researching technology alternatives appropriate to a range of nuclear energy futures.” There is plenty of uranium to sustain even the most optimistic worldwide nuclear power scenarios “for much of this century at least,” says the report.
What about those countries, such as France and Japan, which have been pushing breeders and fuel recycle? “The benefits to resource extension and to waste management of limited recycling in LWRs using mixed oxide fuel as is being done in some countries are minimal,” concludes the MIT study. The cost of uranium is about 2%-4% of the cost of nuclear electricity, notes the study. “Our analysis of uranium mining costs versus cumulative production in a world with ten times as many LWRs and each LWR operating for 60 years indicates a probably 50% increase in uranium costs. Such a modest increase in uranium costs would not significantly impact nuclear power economics.”