The chief environmental benefit from nuclear power comes from the reduction in carbon dioxide (CO₂) emissions when nuclear power replaces fossil fuels. International agreements such as the Kyoto Protocol (1997) and the Paris Agreement (2015) have set targets for reducing CO₂ emissions, and nuclear power is one of the lowest-carbon sources of electricity available.
Nuclear energy sources are also beneficial in reducing emissions of sulphur dioxide (SO₂) and nitrogen oxides (NOₓ). The table below illustrates the dramatic difference.