Solar radiation is not only the driving force behind the Earth’s weather phenomena, it also drives photovoltaic energy production. One day of solar energy received by the Earth exceeds the amount of worldwide energy consumption per year. Exploring this merely inexhaustible source of energy – either by direct transformation of radiant energy into electricity or by indirect energy production via wind, waves, etc. – seems to be the obvious way to go.


In this context, solar radiation measurements are of primary interest for applications like site-specific solar resource assessments, PV performance evaluation, solar resource forecasting, and so on. However, as with most real-world measurement systems, the difficulties are in the details. Reliable and accurate radiation measurements need some knowledge and attention: think of environmental influences (wind, rain/snow, soling), re-calibration (bi-annually), not to mention data processing, spectral effects, etc.