The quality concerns have emerged just after a surge in solar construction. In the United States, the Solar Energy Industries Association said that solar panel generating capacity exploded from 83 megawatts in 2003 to 7,266 megawatts in 2012, enough to power more than 1.2 million homes. Nearly half that capacity was installed in 2012 alone, meaning any significant problems may not become apparent for years.“We need to face up to the fact that corners are being cut,” said Conrad Burke, general manager for DuPont’s billion-dollar photovoltaic division, which supplies materials to solar manufacturers.The solar developer Dissigno has had significant solar panel failures at several of its projects, according to Dave Williams, chief executive of the San Francisco-based company.“I don’t want to be alarmist, but I think quality poses a long-term threat,” he said. “The quality across the board is harder to put your finger on now as materials in modules are changing every day and manufacturers are reluctant to share that information.”Most of the concerns over quality center on China, home to the majority of the world’s solar panel manufacturing capacity.After incurring billions of dollars in debt to accelerate production that has sent solar panel prices plunging since 2009, Chinese solar companies are under extreme pressure to cut costs....“The question is whether things are deteriorating rapidly or whether it’s a few isolated companies not doing so well on their quality control,” she said. “I hear a lot of angst, but I haven’t seen a lot of solid information.”All solar panels degrade and gradually generate less electricity over time. But a review of 30,000 installations in Europe by the German solar monitoring firm Meteocontrol found 80 percent were underperforming. Testing of six manufacturers’ solar panels at two Spanish power plants by Enertis Solar in 2010 found defect rates as high as 34.5 percent.Enfinity operates solar installations in Europe and the United States. Bob Hopper, Enfinity’s chief development officer, said his company had stopped buying Chinese modules because of quality concerns. “Even a small amount of unforecasted degradation in electricity production can have significant economic impact on us,” he said.In the Netherlands, René Moerman, chief strategy officer of Solar Insurance and Finance, said claims had risen 15 percent recently. He said an inspection of a solar plant in Britain in March revealed that 12 percent of the newly installed Chinese-made modules had failed. He said confidentiality agreements prevented him from naming the manufacturer.Other solar developers and installers said they had not experienced quality problems.“The systems we installed in 2012 had the best performing year yet,” said Lyndon Rive, chief executive of SolarCity, the largest residential solar installer in the United States and a buyer of panels from China’s Yingli Solar and Trina.Non-Chinese manufacturers have had quality problems as well. The defective panels installed on the Los Angeles area warehouse, for instance, were made by an American manufacturer. A reporter was granted access to the project on the condition that the parties’ identities not be disclosed because of a confidential legal settlement.First Solar, one of the United States’ biggest manufacturers, has set aside $271.2 million to cover the costs of replacing defective modules it made in 2008 and 2009.
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