Global Solar Irradiation Assesment in Uruguay Using Tarpley's Model and Goes Satellite Images
Abstract
The estimation and characterization of incident solar energy typically involves decades of careful measurements and modeling. In Uruguay, a country with no conventional energy resources (such as coal, oil, natural gas or potentially fissible materials), this process has been initiated only recently. The first systematic efforts on a nation-wide scale resulted in 2009 in the first Solar Map, based on preexisting long-term daily irradiation data from just three sites, two of which equipped with fotovoltaic sensors Abal et al. (2010). These irradiation measurements were correlated with long-term daily sunshine duration records from the national meteorological service (DNM) network, using the well-established Angstr¨om–Prescott methodology Angstro¨m (1924); Prescott (1940). This procedure allowed to estimate monthly averages of daily global irradiation, at twelve sites distributed over the country. This information was presented graphically, using standard interpolation techniques as twelve monthly mean irradiation maps with a spatial resolution of about 200 km. The estimated uncertainties were evaluated between 14% and 19 % of the mean, depending on location and month of the year. This initial effort made clear that new controlled quality measurements were urgently required to obtain reliable data on several points of the target territory. A nation-wide program leading to the establishment of several automatic measuring stations equipped with Kipp & Zonen CMP6 field pyranometers was launched from the national University (UdelaR) and is now in operation Toscano and Cataldo (2011). The first years of controlled global irradiance measurements are now available and a preliminary comparison with the estimates of the Solar Map is being reported in D’Angelo et al. (2011).