Publications Details

Recent advancements in outdoor measurement techniques for angle of incidence effects

King, Bruce H.; Riley, Daniel R.; Robinson, Charles D.; Pratt, Larry

Reflection losses from a PV module become increasingly pronounced at solar incident angles >60°. However, accurate measurement in this region can be problematic due to tracker articulation limits and irradiance reference device calibration. We present the results of a measurement method enabling modules to be tested over the full range of 0-90° by articulating the tracker in elevation only. This facilitates the use of a shaded pyranometer to make a direct measurement of the diffuse component, reducing measurement uncertainty. We further present the results of a real-time intercomparison performed by two independent test facilities ∼10 km apart.