Realisable scenarios for a future electricity supply based 100% on renewable energies

In view of the resource and climate problems, it seems obvious that we must transform our energy system into one using only renewable energies. But questions arise how such a system should be structured, which techniques should be used and, of course, how costly it might be. These questions were the focus of a study which investigated the cost optimum of a future renewable electricity supply for Europe and its closer Asian and African neighbourhood. The resulting scenarios are based on a broad data basis of the electricity consumption and for renewable energies. A linear optimisation determines the best system configuration and temporal dispatch of all components. The outcome of the scenarios can be considered as being a scientific breakthrough since it proves that a totally renewable electricity supply is possible even with current technology and at the same time is affordable for our national economies. In the conservative base case scenario, wind power would dominate the production spread over the better wind areas within the whole supply area, connected with the demand centres via HVDC transmission. The transmission system, furthermore, powerfully integrates the existing storage hydropower to provide for backup co-equally assisted by biomass power and supported by solar thermal electricity. The main results of the different scenarios can be summarized as follows: 1) A totally renewable electricity supply for Europe and its neighbourhood is possible and affordable. 2) Electricity import from non-European neighbour countries can be a very valuable and substantial component of a future supply. 3) Smoothing effects by the use of sources at locations in different climate zones improve the security of the supply and reduce the costs. 4) A large-scale co-operation of many different countries opens up for the possibility to combine the goals of development policy and climate politics in a multilateral win-win strategy. To aid implementation, an international extension of the ideas of the German energy feed law (or similar other schemes around the world) is proposed for the follow-up treaty to the Kyoto climate accord. (au)