SAN JOSE, Calif., June 25, 2013 /PRNewswire/ -- SunPower Corp. (NASDAQ: SPWR), a leading solar technology and energy services company, and Atlas Material Testing Technology, LLC (Atlas), the global leader in weathering technology and services, today announced that the high-efficiency SunPower® E20/327 Solar Panel underwent the rigorous Atlas 25 +® Comprehensive PV Durability Testing program and, upon completion, showed less than two percent power degradation, an outstanding result for the program. The certificate was issued by Atlas' partner, SGS, the world's leading inspection, verification, testing and certification company. The Atlas 25 + testing protocol includes long-term environmental exposure that requires modules to have less than eight percent degradation over the testing period in order to receive SGS certification. The program is designed to subject modules to the environmental degradation stresses which can be expected over long-term service. In addition to achieving less than two percent power loss, the SunPower E20/327 Solar Panel also passed two additional criteria: no visual aesthetic changes and no change in electro-luminescence. "Our Atlas 25 + third-party testing program replicates harsh weather conditions that solar panels will undergo during their lifetime," said Richard Slomko, Global Testing Manager at Atlas Testing Services. "We are pleased that SunPower's high efficiency solar panels not only withstood these conditions, but well exceeded the power degradation criteria of eight percent in addition to testing well on all criteria. We are delighted that SunPower has received outstanding results from our Atlas 25 + program." Atlas 25 + is a proprietary multi-dimensional durability test program designed to subject photovoltaic modules to the environmental degradation stresses which can be expected over long-term service. It provides manufacturers with the data they need to demonstrate long-term durability and to support warranty and performance claims while reducing the costs associated with aftermarket product failure. The program exposes solar panels to a series of stresses, including UV-A/UV-B exposure, salt spray corrosion, condensing humidity, solar/thermal humidity cycle, solar/thermal humidity freeze cycle, Arizona and Florida solar tracking – including peak summer – and initial, final and multiple interval measurements. "SunPower produces the most reliable solar panels. The results of the demanding Atlas 25 + testing criteria confirm our position," said Tom Werner, SunPower president and CEO. "We want to provide our customers with third-party validation of the efficiency and reliability of our solar technology. We are pleased and honored to be the only solar company to date to receive this test's highest rating."