Solar irradiation data is scarcely available in regions suitable for solar energy applications. For the design of solar power
plants, accurate but affordable measurements are indispensable. Accurate sensors are little appropriate for remote
stations due to soiling, high power consumption and elevated costs. Rotating shadowband devices represent a
prospective alternative. This paper describes new corrections for the systematic deviations of a Rotating Shadowband
Pyranometer (RSP) with an integrated temperature probe. The correctional functions were developed on data from 23
different RSPs over an entire year. An average reduction of the root mean square deviation of direct normal irradiation
from above 6.5% to below 2.5% was achieved.