A New GIS‐based Solar Radiation Model and Its Application to Photovoltaic Assessments

Abstract

The solar radiation model r.sun is a flexible and efficient tool for the estimation of solar radiation for clear‐sky and overcast atmospheric conditions. In contrast to other models, r.sun considers all relevant input parameters as spatially distributed entities to enable computations for large areas with complex terrain. Conceptually the model is based on equations published in the European Solar Radiation Atlas (ESRA). The r.sun model was applied to estimate the solar potential for photovoltaic systems in Central and Eastern Europe. The overcast radiation was computed from clear‐sky values and a clear‐sky index. The raster map of the clear‐sky index was computed using a multivariate interpolation method to account for terrain effects, with interpolation parameters optimized using a cross‐validation technique. The incorporation of terrain data improved the radiation estimates in terms of the model's predictive error and the spatial pattern of the model outputs. Comparing the results of r.sun with the ESRA database demonstrates that integration of the solar radiation model and the spatial interpolation tools in a GIS can be especially helpful for data at higher resolutions and in regions with a lack of ground measurements.

A clear sky irradiation assessment using the European Solar Radiation Atlas model and Shuttle Radar Topography Mission database: A case study for Romanian territory

“…Numerous solar database and estimation tools are available worldwide, a significant progress being made in this direction in last time. 25,26 Among of these should be mentioned PVGIS, SoDa, HelioClim, NASA-SSE (Surface Meteorology and Solar Energy programme), Meteonorm, Satel-light, etc, where, in order to account the spatial distributions of solar radiation, the solar radiation models have been integrated within geographical information systems, obtaining so very powerful solar radiation analysis tools and database. The SoDa project is based on the information acquired by processing the satellite images, most of the database resources being available in the graphical and tabular format, the database being available through SoDa services.…”

Methods and tools to evaluate the availability of renewable energy sources

“…Therefore precise solar irradiation data are of utmost importance for successful planning and operation of solar energy systems. Solar irradiation means the amount of energy that reaches a unit area over a stated time interval, expressed as Wh/m 2 (Suri and Hofierka, 2004). Solar radiation can be divided into direct and diffuse radiation.…”

“…The top down approach starts with the computation of an available solar energy potential. This is expressed as the physically available solar radiation on the earth's surface, that is influenced by various factors, as described in Suri and Hofierka (2004).…”

Incorporating shading losses in solar photovoltaic potential assessment at the municipal scale

“…by aerosols and clouds) (Suri & Hofierka, 2004;Remund et al, 2003). Accordingly a successful and accurate simulation is conditional upon (i) the determination of the solar vector; (ii) the input of local terrain or a Digital Surface Model (DSM, which in this case, is reconstructed from LiDAR data); and (iii) the choice of an irradiation/ shading model, which may have its own required parameters (e.g.…”