Small, nearly meltdown-proof nuclear reactors are receiving a big boost from the U.S. Department of Energy. The department will give a company in Corvallis, Oregon, as much as $226 million to develop so-called "small modular reactors," which can be used with many local power grids that can't accommodate conventional nuclear reactors. Because of the extremely low likelihood of meltdown, the next-generation, small-scale reactors are safer than many currently operating reactors, engineers say. The company, NuScale Power, plans to encase their reactors in something akin to a large thermos, which would sit at the bottom of a pool. If a reactor fails and threatens to overheat, the container would fill with water and remove excess heat without pumps or valves, which can sometimes fail. The Energy Department's investment is the second one in a $452 million, multi-year program to accelerate the development of such reactors...