A 2006 study from the International Journal of Nuclear Governance looked at various types of reactor systems and how they might best be combined to meet our future energy needs. The conclusion may surprise those who see the different nuclear power systems as either/or choices:
Finally, the last option examined consists in a combination of the three reactor types considered in the course of this study, light water reactors, fast neutron reactors and molten salt reactors. This appears to be, by far, the most efficient scenario. It allows the fastest and most flexible deployment as well as the fastest and most flexible stopping of nuclear power if such a decision were to be made. The role of the fast neutron reactors is also to close the U-Pu fuel cycle and the amounts of plutonium and minor actinides produced are significantly smaller than in the preceding options. As a result, waste management is made simpler and easier to implement. Nuclear power deployment in this case is sustainable and efficient, the use of fissile matter and the production of wastes are optimized.
Obama and the DOE may have taken steps to kill the Yucca Mountain repository project, but opponents aren't ready to quit fighting it until they see a tombstone with R.I.P. placed over the entrance. All the more reason why we need to close the fuel cycle and eliminate the problem of long-lived nuclear wastes. As Stephen Chu told the Senate Energy Committee last March, we can use fast reactors and recycling to deal with the problem. If our politicians would move in that direction, we could eliminate the need for Yucca Mountain. Too few of our policymakers even know IFRs exist, though—a situation we're doing our best to change. Fortunately, Obama's picked some savvy scientists for top positions in his administration, so if he can get past the politics of nuclear timidity we may see some real progress.