With its funding priority ´Research for the Sustainable Development of Megacities of Tomorrow´, the German Federal Ministry of Education and Research is focusing on energy and climate-efficient structures in nine fast-growing cities as they offer the opportunity for sustainable urban development. The programme supports projects on various topics: Transportation Management (Hefei, China), Energy and Climate Protection (Gauteng, South Africa), Urban Agriculture (Casablanca), Adaptation Planning (Ho Chi Minh City), Solid Waste Management (Addis Ababa), Water Management (Lima), Resource Efficiency (Urumqi, China), New Town Development (Tehran-Region) and Governance for Sustainability (Hyderabad, India). Outcomes have been generated in six thematic fields of action, serving as a structure for the book series. The books offer a variety of good practice, ranging from analytical instruments and strategic models to realised pilot-projects, innovative technologies, and locally implemented processes. Vol. 1: Energy and Sun Sustainable Energy Solutions for Future Megacities Solar energy is in focus worldwide. So is the role of cities and public governments for creating a more sustainable urban future. This volume highlights the role of solar energy and other solar related energy technologies for a low carbon and sustainable energy system, particularly for cities and city regions in the South. The articles refer to solar energy generation technologies, smart city planning concepts, as well as ‚passive‘ solar building design approaches. Thus, the volume takes a broad and applied approach by analysing projects and different solutions for a more efficient and solar oriented building design and technology implementation.