An assessment of the solar potential of roofs within a web-based solar cadastre : case study: Bolzano and Bressanone, Italy

Abstract

In the last decade the energy issue became a crucial component of ecologically and economically sustainable urban development. The conventional energy sources such as oil, gas and coal are tending to decrease, whereas the renewable energy sources such as solar energy, wind power, hydropower, biofuel, biomass and geothermal energy are making a great contribution into producing electric energy, domestic hot water, heating and motor fuels. Moreover, solar technologies are quite mature already and offer a variety of technical solutions for on-site energy generation. Along with clean and sustainable energy production photovoltaic systems could be installed for a reasonable cost, therefore, their use is growing and private users as well as local authorities demonstrate wide interest in identifying areas suitable for mounting the solar modules. Based on LIDAR (Light Detection and Ranging), a remote sensing technology, precise surface and terrain models can be constructed for evaluation of solar radiation distribution and shadowing at each location. Furthermore, for photovoltaic potential estimations it is necessary to include the information about ambient temperature and parameters of the considered photovoltaic technologies. To proceed with this assignment, the information should be merged and visualized in a convenient way for the end user, which is not trivial. The proposed solution includes development of the WebGIS Solar Tirol application, a state-of-the-art technology, which offers immediate access to the information about irradiance distribution, electrical energy, emission savings and photovoltaic output on building roofs within a single environment. Moreover, the approach doesn-t require the installation of additional software and uses open-source, data standards and APIs. The tool is implemented in a three layer architecture: user interface, application server and spatial database. Therefore, the contribution of the research includes an integration of the methodology for the solar potential estimations into the Web environment. Moreover, the WebGIS Solar Tirol is developed within an existing SDI that provides easy access for collaboration and distribution of solar potential data. The objective of the application is to increase environmental awareness among the residents and provide private users and authorities with comprehensive information for the planning and installation of the solar power systems within an intuitive environment. The results represent an preliminary assessment of solar potential characteristics that can be used to support management decisions regarding investments in the solar systems. The research is applied to the study area in the Autonomous Province of Bolzano (Alto Adige / Südtirol), Northern Italy. The region of South Tyrol has great potential for developing solar energy due to a favorable geographic location, political measures and economic instruments designed to improve the energy efficiency. The combination of cool temperatures and large amounts of solar radiation provides ideal conditions for the solar power systems. However, the complex mountain landscape makes an assessment of solar potential challenging.