This translation of a German title, which was enthusiastically received by a wide audience, collects contributions by leading and well-known scientists in the area explaining the technical basics of photovoltaic, solar thermal energy, wind and water power as well as geothermal energy. In an easily accessible yet sober way, the book offers a solid overview of the possibilities offered by environmentally friendly techniques, energy conversion, storage, and transportation, discussing the topic without any misplaced ideology.The editors are experienced journalists and illustrate the text with simple diagrams and information boxes, printed in full-color throughout.For applied physicists, engineers in power technology, engineers, and anyone interested in natural sciences.