Nuclear Power as a Climate Change Mitigation Option: a Modelling Approach

Sammanfattning: Although nuclear power can provide electricity with very low life cycle carbon emissions and thus reduce the cost of climate change mitigation, it also brings along many specific challenges: accident risk, need for radioactive waste management and nuclear weapons proliferation risk. Due to this controversial nature nuclear power, among other energy forms, has been relatively little studied in a climate mitigation context. This thesis aims to provide some insight into the possible role of nuclear power in climate change mitigation. In the first paper we assess the impact of potential nuclear expansion and advanced nuclear cycles on climate change mitigation cost and reflect on this expansion’s relation to nuclear weapons proliferation risk. We find that nuclear power can reduce the mitigation cost around 20%, and new reactor types and advanced uranium extraction methods provide a significant part of the savings (10%). To materialize those savings however the number of reactors would need to increase tenfold by 2070, which implies an increase in enrichment and/or reprocessing facilities, technologies that are directly related to proliferation risk. We show that even if reprocessing can be made proliferation safe as some scientists believe, the switch to a closed fuel cycle that does not need enrichment will take more than the remainder of this century under a cost minimising condition, and therefore proliferation risk cannot be eliminated. In the second paper we investigate further the mitigation cost reducing ability of nuclear power by subjecting our model to numerous parameter variations and a Monte Carlo analysis. We observe that nuclear power can provide significant cost savings in almost all cases and that the expansion of nuclear power is dependent on climate policy. In addition we discovered that the capacity for carbon capture and storage plays a significant role in cases of a nuclear phase out and high climate sensitivity but is inconsequential if nuclear expansion is allowed.