Solar energy seems to be enjoying a new day in the sun, but that could be threatened by a reported rash of defective panels, caused by a high pressure to cut costs.
There are no industry wide figures about defective solar panels. And when defects are discovered, confidentiality agreements often keep the manufacturer’s identity secret, making accountability in the industry all the more difficult.
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.
Executives at companies that inspect Chinese factories on behalf of developers and financiers said that over the last 18 months they have found that even the most reputable companies are substituting cheaper, untested materials. Other brand-name manufacturers, they said, have shut down production lines and subcontracted the assembly of modules to smaller makers where they have little to no control over quality. Photovoltaic modules at a Shanghai laboratory in 2012 found the defect rate had jumped from 7.8 percent to 13 percent.
The heart of a solar panel is a photovoltaic cell that generates electricity when struck by sunlight. Among the most critical components is a thin film that protects the cell from moisture, and encapsulate that seals the cell between layers of glass. Inspections have found some manufacturers had been constantly switching to cheaper materials, including some whose use-by date had expired. If the materials aren’t good or haven’t been thoroughly tested, they won’t stick together and the solar module will eventually fall apart in the field.
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 found 80 percent were underperforming.
Non-Chinese manufacturers have had quality problems as well. One company now offers a comprehensive insurance policy to customers and has established its own testing laboratory in the San Francisco area.
One industry executive, said manufacturers needed to be held accountable and advocated creating testing labs not beholden to the industry that would assess quality. “We need to start naming names,” he said.
The lesson learned is that in order for solar power to continue brightening our world, manufacturers must be held accountable for their production standards. So be vigilant when selecting solar contractors and make sure you know whose solar modules are being used and check for reliability and guarantees. Leasing programs may help as the lessor maintains performance and warranties the installation during the leasing term.