This book pursues the fundamental idea of using renewable energies in a rational and economic way in order to develop a climate-friendly electricity supply. As the most cost efficient solution, an electricity network for the whole of Europe and parts of Africa and Asia must be found. The sources of renewable and partly decentralised electricity generation could be connected in a comprehensive power supply to meet the electricity needs of an entire region.Czisch examines different scenarios for a CO2 neutral electricity system under different political, technological and economic conditions for Europe and its closer surroundings. The aim is to find in each variation the economically optimal solution, whereby the supply area embraces approximately 1.1 billion inhabitants and an electricity consumption of roughly 4000 terrawatt-hours per annum (TWh/a). 3