Long-term low greenhouse gas emission development strategies for achieving the 1.5 °C target - insights from a comparison of German bottom-up energy scenarios

The Paris Agreement calls on all nations to pursue efforts to contribute to limiting the global temperature increase to 1.5 degrees C above pre-industrial levels. However, due to limited global, regional and country-specific analysis of highly ambitious GHG mitigation pathways, there is currently a lack of knowledge about the transformational changes needed in the coming decades to reach this target. Through a meta-analysis of mitigation scenarios for Germany, this article aims to contribute to an improved understanding of the changes needed in the energy system of an industrialized country. Differentiation among six key long-term energy system decarbonization strategies is suggested, and an analysis is presented of how these strategies will be pursued until 2050 in selected technologically detailed energy scenarios for Germany. The findings show, that certain strategies, including the widespread use of electricity-derived synthetic fuels in end-use sectors as well as behavioral changes, are typically applied to a greater extent in mitigation scenarios aiming at high GHG emission reductions compared to more moderate mitigation scenarios. The analysis also highlights that the pace of historical changes observed in Germany between 2000 and 2015 is clearly insufficient to adequately contribute to not only the 1.5 degrees C target, but also the 2 degrees C long-term global target.