There are hard limmits on the efficiency of any heat engine; the plant described here is actually doing pretty well. And, hey, fuel is cheap; the energy density

There are hard limmits on the efficiency of any heat engine; the plant described here is actually doing pretty well. And, hey, fuel is cheap; the energy density of uranium is pretty spectacular. http://en.wikipedia.org/wiki/Thermodynamic_efficiency http://en.wikipedia.org/wiki/Thermodynamic_efficiency