Many industrial solar farms now employ "tracker" technology to align panels with the sun's arc. But rooftops are often bad places for such heavy machinery, and engineers worry that if panels tilt too tall, they may be buffeted by the wind and fall to the ground.
Now a startup in Pasadena, California, has come up with an alternative design that may make rooftop tracking easier: a machine that lies closer to the ground and tilts both up and down and in a 360-degree motion. By following the sun, it can increase power output by 20%, the company behind the design says (and perhaps more under certain conditions).
"It takes a lot of buildings where solar wasn't attractive and makes it attractive because you get such a boost in economics," says Bill Gross, CEO of Edisun Microgrids.
Conventional panels fit inside the PV Booster's rack, which is controlled by an onboard microprocessing unit. The machine senses the sun's rays, moving itself into optimal position throughout the day. Gross says it's no more difficult to install than a conventional panel system.
It does raise the overall installation cost by 10%, he concedes, but this is more than offset by a 31%-36% higher production output. And in places where utilities charge more for power when grid demands are greatest ("time-of-use pricing"), the economics could be better still. The system has the added advantage of producing power in the later afternoon, when the power from traditional panels falls off, but when household needs are highest.
Gross says the PV Booster will be installed first on top of buildings in New Jersey, California, and Hawaii. At the moment, it's just for commercial roofs with tilts of no more than 10 degrees. But given the benefits of tracking, it can't be long before they're standard on all solar installations.
[Cover Illustration: bagotaj/iStock]
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