Modeling Clouding for the Automated Solar Potential Analysis on Urban Roof Areas based on LiDAR

Abstract

Renewable energies as an additional component to conventional energies takes center stage of the current solutions attempt for decrease of the global climate change besides energy saving. The use of solar energy saves enormous capabilities. Using Geo-Informatic (GI) science, it is possible to give innovative impulses to the solar market, especially by supporting new technologies taking care that renewable energies can run without any subsidy in the near future. Within the research project SUN AREA of the University of Applied Science of Osnabrück (Germany) a method was developed, which makes it possible to examine each building of a large region for the ability of location regarding the use of solar energy and calculate the energy potential for photovoltaic plants and solar thermal systems. Based on high resolution LiDAR (Light Detection and Ranging) data and digital topographic data (building outline) we developed an automatic running computer aided analysis method to identify high potential urban roof planes for the use of solar power with Geographic Information Systems (GIS). To detect qualified buildings for solar plants, necessary location factors, such as outer form, roof size, slope, exposition and clouding have to be taken into account. At this the factor shading plays in particular a very important role. In order to be able to operate a solar plant economically, a shading-free location is decisive. This aspect is to be lit up in the context of this paper. As result of the solar potential analysis a numerical description of each roof as well as a cartographic visualization is obtained. The pilot region was the city of Osnabrück in Germany with an overall area of 120 km2 and 70.000 buildings. In order to present all results, Germany´s first solar roof register based on an internet GIS application was developed by the project team to spread the information to the public (www.osnabrueck.de/sun-area).