Characterization of global irradiance sensors for use with PV Systems

Global irradiance sensors supply essential information in the business of planning and operating PV Systems. Errors and uncertainty in irradiance measurements propagate to uncertainty about performance and profitability. PV Performance Labs initiated the PVSENSOR project in 2014 to more fully characterize commercial irradiance sensors, with the objective of reducing such uncertainties. In the first phase of indoor testing we tested 21 pairs of instruments using multiple solar simulators (both pulsed & continuous, large area & small), environmental chambers, spectrally selective and neutral density filters, and corresponding reference instruments. This paper provides a first look at many of the results, highlighting differences between sensor categories.