The first PV module qualification tests were developed by the Jet Propulsion Laboratory (JPL) as part of the Low-Cost Solar Array program funded by the U.S. Department of Energy , , , . Elements of the Block V qualification sequence include: twisted-mounting surface test.
Accurate determination of PV performance requires knowledge of the potential measurement problems and how these problems are influenced by the specific device to be tested. This section covers common PV measurement techniques and shows how potential problems and sources of error are minimized.
The calibration and use of radiometric instruments such as pyrheliometers, spectroradiometers, and pyranometers is a subject that is beyond the scope of this chapter, but these instruments are important for PV measurements. A number of standards for radiometric instrumentation are available , , , , , .
Part 3, still a Committee Draft, describes the calculations for PV module energy rating. Due to the complexity of the procedure of the standard, several laboratories have developed simplified procedures for energy rating of PV modules , , , , , .
Because solar cells convert light to electricity, radiometry is a very important facet of PV metrology. Radiometric measurements have the potential to introduce large errors in any given PV performance measurement because radiometric instrumentation and detectors can have total errors of up to 5% even with careful calibration , .
D. Myers, K. Emery, C. Gueymard, Proposed reference spectral irradiance standards to improve photovoltaic concentrating system design and performance evaluation, in: Proceeding of the 29th IEEE Photovoltaic Specialist Conference, IEEE, 2002.