Shelli DeRobertis 9:19 p.m., May 22
Touring Electrical Union's Solar Facilities
The International Brotherhood of Electrical Workers and National Electrical Contractors Association hosted a tour this morning of their rooftop solar system at the main training center for apprentice electricians in the county.
The panels produce 90 kilowatts of energy, with another 72 or more coming from another set installed on top of the IBEW union hall. During peak daytime production periods, the panels produce about 180% of the building’s energy consumption. The rest is fed back into the power grid, where it supplies neighboring buildings with a portion of their power.
The system is installed above the surface of the roof, and at an angle to take advantage of the western-setting sun to maximize production in the afternoon and early evenings, as most training classes held at the building occur at night. The angled installation was also designed to cool the panels, which generate electricity more efficiently when not overheated.
A fringe benefit of installing solar panels, decreased building heating and cooling costs, was discussed in a UCSD study reported earlier this week. Another bonus touted by the union: decreased wear and tear on the sheltered portions of the roof. “Most commercial buildings will have an estimated life span of 15 to 20 years for a roof. We’ve had these panels up almost 11 years and the roof under them is still holding up very well,” commented one union representative. He expects the roof to last anywhere from 50% longer to twice as long as buildings not shielded by solar.
One purpose of the installation was to train apprentices in the installation and maintenance of advanced solar systems. “We want to get [workers] on a rooftop, simulating working being tied off on a residential roof,” explained Patrick Knighton, director of San Diego electrical training, while showing a small crowd around a plywood pitch assembled near the main panels. All of the panels, power inverters, and related equipment were installed by students during the past decade. Knighton said he’d also taken student groups for training at homes of union members who were installing solar.