An Economically Viable 100% Renewable Energy System for All Energy Sectors of Germany in 2030

To be able to fulfil the Paris Climate Agreement and keep global warming with reasonable confidence at a maximum of 1.5 °C above pre-industrial levels, Germany must set an end to all greenhouse gas emissions by 2030. At the core of this task is the switch to 100% renewables across all sectors on the same time horizon. Conventional technologies fueled by fossil and nuclear energies are, according to the vast majority of current cost calculations, energetically inefficient, too expensive, and too slow in expansion to be able to deliver a substantial contribution to rapid climate protection. We present the first comprehensive energy scenario that shows the way to 100% renewable energy for all energy sectors by 2030. The result of the calculations is a cost-effective energy system that is compatible with the German share of necessary greenhouse gas reduction. This study shows a target system of generation, conversion, and storage technologies that can achieve the transformation to 100% renewable energy in all energy sectors—electricity, heat, and mobility—in time and at competitive costs below the costs of the current system. Moreover, we demonstrate the huge cost effect that arises if southern Germany renounces its onshore wind resources and find that this would substantially increase the need for high-voltage direct-current transmission capacity.