When the Sun Bears Down Hard

Charlie Northcross just wanted to install solar panels on his building, but in the process he participated in an innovative development for mounting equipment. Northcross is chief executive of George B. Woodcock & Co., a maker of foam packaging materials in Chatsworth. After deciding to switch to solar power and contracting with SolarCity Corp. for installation, he discovered several technical challenges at his particular location. First, the roof couldn’t bear the weight of the metal grids, brackets and ballast that’s typical for residential solar jobs. Second, high winds occur often in Chatsworth, so Northcross wanted to keep the panels low to the roofline to avoid strain on the underlying structure. SolarCity, which is based in San Mateo and has done about 1,700 installations across the country, decided to use the company’s new LightMount non-penetrating rack system. It’s designed to evenly disperse the weight of the panels, and because the mounts are made of the same material as the roof, it doesn’t require anchors or connectors. “We used a new mounting system they had never used before, but we said, ‘If you will test it, we’ll use it,’” Northcross said. Erik Fogelberg, SolarCity’s vice president of commercial sales, said a typical warehouse roof is coated with EPDM, a type of white synthetic rubber. The LightMount brackets are made of the same stuff, and workers directly “weld” the mounts to the roof by melting the rubber. “This is a non-penetrating system, which means no holes punched in the roof,” he said. “That way it maintains the warranty of the (solar) system and the rooftop.” Woodcock did not disclose the project’s cost. The final product is one of the Valley’s largest commercial solar power installations, capable of producing 224 kilowatts, enough of cover about 90 percent of Woodcock’s usage. Northcross estimates it could lower the company’s electric bill from about $10,000 a month to $1,500. And, if it ever puts the 86,000-square-foot building on the market, the savings will be a nice selling point. “Our energy bills will be cut substantially,” he said. “We figured it was a payoff we can’t pass up.” For SolarCity, the experience demonstrated the viability of LightMount on EPDM roofs and that could mean big business in the future. “It’s going to open up more rooftops to solar as it lessens weight constraints,” Fogelberg said. – Joel Russell