Carbon Leakage of Nuclear Energy – The Example of Germany

Abstract

Carbon leakage is the increase in emissions outside a region as a direct result of the policy to cap emissions in this region. Nuclear energy is a low carbon technology but it is not emission free. Lifecycle analyses of nuclear energy find an average carbon intensity of 66g CO2/kWh of which the largest part (38%) is generated in the front end of the nuclear fuel cycle (uranium mining and milling). Besides the CO2 emission there are also other environmental and health impacts that are associated with the uranium milling and mining activities. In Germany nuclear energy use is a controversially discussed topic. In 2002 the out-phasing of nuclear energy by 2022 was decided. In 2010 a new government passed a life time extension of the 17 power plants by on average 12 years, seeing nuclear energy as an important bridging technology to reach Germany’s ambitious climate goals. This chapter calculates the carbon leakage that is expected to result from the 2010 life time extension. Due to the nuclear incident in Japan in March 2011 the debate about the time plane for the outphasing for nuclear energy started again in Germany. At the time of writing, it is unclear when and how the out-phasing process in Germany will take place. This work is therefore to be seen as an exemplary study on the issue. Uranium is not mined in Germany and it is not easy to trace the origin of the imported uranium. But it can be said that close to 100% originate from outside of Europe. This work calculates the expected amount of carbon leakage from German nuclear energy use until 2036. The calculations are based on an energy scenario of the German government, the lifetime extension of nuclear power plants and carbon emission resolved by region for each production step from life cycle analyses. It is important to incorporate the aspect of carbon leakage in the international discussion about climate friendly energy solutions. This assures fairness and transparency and avoids that countries with emission limits gloat over mitigation achievements whose burden has to be carried by other regions.