Tim Worstall published an article titled “Nuclear Power and CO2 Emissions” on 1 November 2005. Well worth a read.
The topic has been discussed several times before and Tim does an admirable job of trying to be fair to people who baldly assert that nuclear power has measurable emissions of polluting gases that are worse than those of solar, wind and even biomass. If you want a more detailed study and and explanation of the assumptions, probably one of the best sources is the ExternE project at http://www.externe.info/.
I guess I am simple minded, but here is my logic on the subject. If it is possible to seal a nuclear power plant inside a submarine full of people without providing any means of removing “emissions” and then to operate that submarine for months at a time, then it seems to me that the emissions are pretty minimal. Please do not try that experiement with a biomass generator, even for a couple of minutes.
Of course, I recognized milling, enrichment, and manufacture of commercial nuclear fuel, concrete, and steel all consume energy, but all of that energy can be in the form of electricity. It is certainly possible to produce electricity in nuclear power plants that do not produce any emissions either. Pretty obviously, if the processing is done in France, for example, the polluting gases emitted while producing commercial nuclear fuel and plant construction materials is pretty darned low.
Anyway, judge for yourself.