Sandia and Photovoltaic Performance Labs, Inc. have partnered on the PVSENSOR project to measure, characterize, and understand modern radiometric instrument intricacies. Such instruments are used to measure the amount of sunlight impinging on a plane and are primarily used as reference devices for PV systems.

Two identical sets of 21 radiometers are mounted on the Photovoltaic Systems Evaluation Lab’s (PSEL’s) two-axis solar tracker at Sandia. After initial characterization, one set will go to Germany for year-long testing at Photovoltaic Performance Labs, while PSEL tests the other.

PVSENSOR project1_(web) SNL 2-axis tracker at PSEL_(web)
The two sets of 21 radiometers mounted on the two-axis tracker. A wider-angle view of a two-axis tracker at Sandia’s PSEL.

The performance of different radiometers may vary due to factors such as temperature, incident angle and spectral content of incoming light, and temporal response to light level changes. The PVSENSOR project will provide data on the performance of radiometric instruments to PV system designers and modelers, helping them to select appropriate and cost-effective reference devices for use in PV systems.