In recent years, the distributed generation of energy has undergone a great development, since it allows to bring the points of generation closer to the points of consumption, reducing the losses due to the transport and decentralizing the distribution grid. In this context, the solar energy in urban environments, the cities, has a key role, as it is the most abundant energy source. This book discusses and compares various solar tools and presents a new solar radiation model, based on the Sky View Factor concept, for the analysis and estimation of solar radiation on façades of buildings. This new model shows more precise data, that allow obtaining more accurate electricity production simulations, economic evaluations and returns. Therefore, this book results very useful for both architects and engineers who are interested in solar collector systems in cities, for the production of photovoltaic and thermal energy and also for professionals and researchers who study the illuminance and the irradiance in rooms and façades.