'Smart' solar panels wring more juice to lower cost
More companies are developing electronics fitted directly onto solar panels to improve the "energy harvest" and reduce losses due to mismatches in output in an array of connected panels.
In an industry-wide effort to cut the cost of solar power, panel manufacturers are using electronics to boost efficiency and get more bang for the solar buck.
Suntech, a large Chinese panel maker, is partnering with three companies to integrate electronics onto its panels to optimize the output and ease installation. "Smart" solar panels is likely one of the technology trends to emerge at the annual Solar Power International (SPI) conference next week in Los Angeles.
Companies developing these technologies say that making efficiency improvements in panels represents one of the best ways to improve the economics of solar photovoltaics.
Because of higher manufacturing volumes and price competition, the cost per watt of solar panels themselves continues to decline. But about half of the end cost to consumers--called the balance of system in industry parlance--is tied up in the wiring, electronics, and installation.
Enphase Energy on Tuesday said that it will collaborate with Suntech to explore the development of an "" which uses Enphase's microinverters. Enphase next week at SPI plans to demonstrate the latest version of its microinverter technology, which will be available in the first half of next year, according to the company.
Traditionally, arrays of solar photovoltaic panels are wired to an inverter which converts the aggregated direct current from panels to household alternating current. In the past few years, companies have developed improved microinverters which are fitted directly onto the panel. In addition to simplified wiring, microinverters boost the overall output of an array because shading of one panel won't affect other panels connected to it, as happens with a centralized inverter.
Start-up Azuray Technologies announced a deal on Tuesday to collaborate with Suntech using different power electronics technology. The company has developed a direct current-to-direct current converter which can be fitted onto solar panels to increase the "energy harvest" of an array of panels affected by shading or a mismatch. With its system, output of an array of panels can be improved by as much as 25 percent.
Another company, Tigo Energy, said that its Energy Maximizer Solution, a small box which can be fitted onto panels, will be used by Suntech. Tigo's locate underperforming panels in a string and control the flow of current so that a single panel doesn't lower the output of other connected panels, according to the company.
Meanwhile, National Semiconductor said that itshave been integrated into junction boxes of panels made by Green Energy Solar.
Think tank the Rocky Mountain Institute earlier this week presented results from an industry study on reducing balance of system costs in solar. Its study found that electronics, including inverters, represent about 30 percent of the balance of system cost.
New power electronics, particularly AC panels, offer one of the best areas to use technology to lower the costs, it said. Bigger savings can be done by using standardized components in racking and other structural components and by streamlining the business process around installation.