After analyzing studies that concentrate on investigating the power supply development and this author’s study of real generation data of renewable energies from 2007 this thesis researched whether it is manageable to guarantee 100 % power supply based on renewable energies only for the year 2025. Thus, a simulation of the power production in selected individual self-sustaining Federal States on an hourly basis was conducted. Furthermore, the individual energy demand of these States and the load needed if combined as a network was looked upon in the simulation.

In each particular surveyed Federal State (self-sustaining system) a 99 % guarantee of power supply on the basis of renewable energies is possible. In the self-sufficient approach the energy storage made up 0.5 % of the yearly consumption of all considered Federal States. Connecting the individual examined States to a network would result in the possibility of a capacity reduction of the energy storage up to 75 % and a guarantee - raise of the power supply at the same time. The influence of a demand site management on the security of supply in the presented simulations is marginal.

Therefore the predictions of the energy industry, that a shutdown of conventional power plants would result in an energy gap, were devitalised and rebut for the observed Federal States.