The recent energy crises of natural gas supply in Europe caused by the Russian invasion of the Ukraine have put a spotlight on the interdependence between the energy transition towards climate neutrality and security of supply of conventional fuels from to today until 2030 and 2035. This paper therefore assesses the impact of a sustained energy crisis and resulting higher fossil resource prices, in particular for natural gas and oil, and options for dedicated measure to reduce the dependence on imports in particular of natural gas and oil. The results are based on a common scenario approach in the ARIADNE Kopernikus project and are calculated by using the energy system REMod which was used in several important scenario studies recently. There are multiple studies analyzing the German energy transformation considering its national CO2 reduction goals, i.e. with the target of net-zero emissions in 2045 (Brandes et al. 2021; Luderer, Kost, and Dominika 2021; Prognos, Öko-Institut, and Wuppertal-Institut 2021). However, all of them have been published before the current energy crisis in 2022. A second detailed analysis of this paper is the role of heat pumps as they are a central substitution technology of natural gas in the building sector of Germany. As electricity demand by heat pumps will grow, this demand will be analyzed in a statistical analysis of the operation of heat pumps.