Review Paper - Long term scenarios and options for sustainable energy systems and for climate protection: A short overview

Within one decade a fundamental choice will have to be made: Should the energy system follow the historical trends of risky and unsustainable energy use patterns? Or should it take the course towards sustainable development and climate protection, giving top priority to energy efficiency and to a broad mix of renewable energies? Both roads are technically feasible. "Back-casting"-scenarios could help to answer the question, what technological options are available for climate protection and how societal goals can be achieved in a cost-effective way. Lessons learned from world energy scenarios and possible implementation options will be discussed. A case study of the German Parliament´s Enquete Commission on Sustainable Energy Systems will be taken as illustration. The analysis shows that sustainable energy systems can be financed and that economic growth can be decoupled from absolute levels of non-renewable energy consumption by stepping up energy productivity