SunPower Ranks 1 in Photon Yield Test

The frontrunner in the test, which had its yield measured over the full course of 2012, is the SunPower SPR-327NE-WHT-D. This model produced 1,144.1 kilowatt-hours of electricity for every kilowatt of power (kWh/kW). Given the total solar irradiation at the location of the module test field in Aachen, Germany in 2012, this module theoretically could have yielded around 1,202 kWh; its actual yield is equivalent to a »performance ratio« of 95.2 percent.

The two other SunPower modules tested – the SPR-320NE-WHT-D and SPR-245NE-WHT-D) – scored 94.9 and 94.8 percent, respectively. The fourth-placed module, the SRP-220-6PB made by Chinese manufacturer Seraphim Solar System Co. Ltd., managed a performance ratio of 93.6 percent.

The previous year’s test winner, the REC230AE model, made by Norwegian company Renewable Energy Corp. ASA (REC), improved its performance ratio from 90.8 percent to 91.4 percent under 2012 weather conditions – but this was only good enough to reach a 27th ranking. The SunPower modules were not the only new additions to the test field in 2012. In total there were 109 new models added, which led the test field to more than triple in size from 46 products. Four modules were excluded from assessment due to technical reasons. With a total of 151 module measurement results, the PHOTON test is the world’s largest of its kind.

Of the tested solar panels, 72 models exhibited a good to very good performance ratio of 90 percent or higher. Chinese manufacturers represent around 65 percent of the module suppliers in the test, approximately equivalent to their world market share. Eight products made by five different manufacturers (Schott Solar, Conergy, SolarWorld, Aleo Solar and Solon) included in the »90 percent plus« category originate from Germany.

The performance ratios of the best modules in the 2012 assessment do not differ nearly as much as their prices, something those interested in purchasing modules should bear in mind. Nevertheless, there are a number of other qualities apart from yield that are important for a solar module – above all, its long-term stability, a reason for all test products to remain on the test field and continue undergoing yield measurements for an unlimited period. Furthermore, the test also identifies characteristics such as weak-light response and the »homogeneity« of a module, a reference to the consistency of its performance under changing temperature and irradiation conditions.

The results are presented in an extensive overview, covering 46 pages, in PHOTON International – The Solar Power Magazine.