Sustainability assessment of the German energy transition

Abstract Background The goal of the energy transition in Germany is to achieve a sustainable supply of energy. Providing advice for decision-makers to either continue the current transition pathway or implement strategic adjustments requires a comprehensive assessment tool. The authors have developed a Sustainability Indicator System (SIS) consisting of 45 indicators to assess if policy measures implemented so far by the Federal Government are appropriate and sufficient to achieve the energy policy targets and, furthermore, the sustainability targets defined for the German energy system. Methods The assessment is carried out applying the SIS. For each indicator, a linear projection was calculated, based on the past 5 years for which data were available, assuming that this trend will continue in a linear way until 2020. Then, the projected value for 2020 resulting from the trend was compared to the political or defined target for 2020. The assessment was based on distance-to-target considerations, i.e. to which degree the set, proposed or desirable target will be met within the framework of the existing energy policy. The results are illustrated using a traffic light colour code. Indicators with less than 5 years of data available were given a white traffic light since no assessment was possible. Results A profound view on eight selected sustainability indicators that are not already part of the German monitoring process ‘Energy of the Future’ and a comprehensive overview on the sustainability assessment of the German energy system are presented. The results show that 24% of the assessed indicators are rated with a green, 7% with a yellow, 45% with a red and 24% with a white traffic light. This means that it cannot be expected that the sustainability targets defined for the German energy system will be achieved by 2020 without substantial modifications of political strategies and measures implemented so far. Conclusions The developed SIS is a comprehensive decision support and navigation tool with respect to long-term governance of the German energy transition. It aims to assess and monitor the overall sustainability performance of the energy system, to identify unsustainable energy strategies and measures as well as trade-offs and to evaluate the achievements or failures of policies regarding the energy transition. It can also be adapted to assess the sustainability of the energy systems in other European countries.