Do we need site-dependent and climate-dependent module rating?

The efficiencies of solar cells and modules are currently rated at standard reporting/operating conditions (SRC/SOC). Standards for the procedures involved have been given by ASTM and IEC. They are very suitable for the comparison of new technological achievements and efficiencies in the laboratory. However, as far as systems are concerned, there are few locations for PV where the yearly or seasonal energy delivery of a system can be predicted accurately using SRC or SOC efficiencies only. Therefore, the authors propose that international standards be adapted for energy/efficiency rating of cells and modules at realistic reporting conditions (RRC). This would provide a rating to the PV customer which allows him realistic estimates of the energy production of the PV components as a starting point for planning of the installation. This RRC concept is a rating method that fulfils these requirements