The LA Tmes has a post on the effectiveness of nuclear power for mitigating global warming - Nuclear power: less effective than energy efficiency and renewable energy?.
The Environment California Research & Policy Center concluded that launching a nuclear power industry nearly from the ground up is too slow and expensive a process. Energy efficiency standards and renewable energy options are better solutions, researchers said.

Currently, no new nuclear reactors are under construction in the country, and no U.S. power company has ordered a nuclear plant since 1978. All orders for nuclear facilities after fall 1973 were eventually canceled, according to the report.

Meanwhile, building a reactor would probably take around a decade – 2016 at the earliest, the study suggested. Without an existing infrastructure, manufacturing reactor parts with the dearth of trained personnel would be difficult.

But even if the nuclear industry managed to build 100 reactors by 2030, the total power produced would reduce total U.S. emissions only 12% over the next 20 years, which Environment California deemed “far too little, too late.”

The $600-billion upfront investment necessary for the 100 reactors would slice out twice as much carbon pollution in that period if invested in clean energy, according to the report. And given the costs of running a power plant, clean energy could deliver five times as much progress per dollar in lowering pollution.