Greenhouse gas emissions avoided through use of nuclear energy
There are many different electrical generation methods, each having advantages and disadvantages with respect to operational cost, environmental impact, and other factors.
In relation to greenhouse gas (GHG) emissions, each generation method produces GHGs in varying quantities through construction, operation (including fuel supply activities), and decommissioning. Some generation methods such as coal fired power plants release the majority of GHGs when their carbon-containing fossil fuels are burnt, producing carbon dioxide (CO2). Others, such as wind power and nuclear power, give rise to much less emissions, these being during construction and decommissioning, or mining and fuel preparation in the case of nuclear.
Accounting for emissions from all phases of the project (construction, operation, and decommissioning) is called a lifecycle approach. Comparing the lifecycle emissions of electrical generation allows for a fair comparison of the different generation methods on a per kilowatt-hour basis. The lower the value, the fewer GHG emissions are released.
WNA has carried out a review of over twenty studies assessing the greenhouse gas emission produced by different forms of electricity generation. The results summarised in the chart below show that generating electricity from fossil fuels results in greenhouse gas emissions far higher than when using nuclear or renewable generation.
In 2011 the world's nuclear power plants supplied 2518 TWh (billion kWh) of electricity. The following table shows the additional emissions that would have been produced if fossil fuels had been used to generate the same amount of electricity.
||Average lifecycle GHG emissions (tonnes/GWh)
|| Emissions produced from generating 2518 TWh of electricity
||Additional emissions avoided through use of nuclear electricity in place of fossil fuel
||2654 million tonnes CO2
||2581 million tonnes CO2
||2236 million tonnes CO2
||2163 million tonnes CO2
||1846 million tonnes CO2
||1773 million tonnes CO2
||1256 million tonnes CO2
||1183 million tonnes CO2
||73 million tonnes CO2
Comparison of emissions from nuclear and renewable generation
The WNA review of lifecycle emissions from nuclear and renewable generation showed that lifecycle emissions from all the major forms of renewables (solar, wind, biomass, hydroelectric) and nuclear were similiar. Replacing generation from nuclear or renewables with fossil fuels would lead to similar rises in greenhouse gas emissions.
WNA Report: Comparison of Lifecycle Greenhouse Gas Emissions of Various Electricity Generation Sources
IAEA PRIS database http://www.iaea.org/PRIS/WorldStatistics/WorldTrendinElectricalProduction.aspx
CIA The World Factbook https://www.cia.gov/library/publications/the-world-factbook/geos/xx.html.