Fossil fuel-based electricity generation is a major source of greenhouse gas (GHG) emissions. Nuclear power has been proposed as a GHG-free alternative to fossil fuel-based electricity, and debate is currently taking place in Australia on this issue. While it has been shown that on a life cycle basis nuclear power production is not GHG-free, conflicting arguments have been presented on the GHG standing of nuclear power relative to fossil fuel-based electricity

These conflicting viewpoints come about largely due to the effect of ore grade and a degree of uncertainty on the energy consumed in the various stages of the nuclear fuel cycle. As the grade of the ore falls, more ore must be processed in order to extract the same amount of uranium, and the life cycle-based GHG emissions associated with the nuclear power produced from the uranium increases. It is conceivable that at some ore grade these GHG emissions may exceed those from fossil fuel-based electricity for the same amount of power produced. What is this ore grade, what is the likelihood of world uranium reserves falling to this level, and if so, when is it likely to occur ?

A life cycle assessment of nuclear power production focussing on energy consumption (covering the range reported in the literature), GHG emissions and ore grade was carried out to address these questions, and the results compared with fossil fuel-based electricity production. This study is an important contribution to the current debate about the GHG benefits of nuclear power in Australia.