Solar used to be a hard sell. The technology hadn't matured, the components were expensive, performance was often lackluster and payback periods sometimes progressed at a glacial pace.
But times are a-changin': Solar is selling. The main drivers of that growth, of course, are financial. Although recent studies from the Lawrence Berkeley National Laboratory indicate that prices for photovoltaic equipment are generally cheaper on new construction than existing structures, there are enough incentives that facility managers are increasingly turning to solar for existing buildings as well.
According to Lawrence Berkeley, the installed cost of commercial photovoltaic systems completed in 2010 fell by roughly 17 percent when compared to the year before, and fell by an additional 11 percent within the first six months of 2011.
Facility managers interested in solar power need to determine where best to locate photovoltaic modules and the related components. Ground-mounted modules allow for easy access, but maintenance is minimal for the modules, so access is largely a non-issue. The real benefit of ground-mounted modules is that they can be set up without any kind of structural calculations for an organization's buildings.
Roof-mounted modules have a distinct set of benefits. Some people don't like the way solar modules look. If that's the case, there are few better places to locate panels than on rooftops. The panels usually require little more than an annual cleaning, which can be wrapped into other rooftop maintenance duties.
The Oakland, Calif., plant of Feeney Wire has a 380-panel rooftop photovoltaic array that can produce as much as 90 kilowatts. The array is located on two buildings — one metal structure and one wooden-framed. The system clips cleanly onto the metal roof, while on the wooden structure it is self-ballasting and uses polymer stands that do no damage to the existing roof.
"There was no need for any roof penetrations on the building, except for the main power conduit, so it's very clean," says Andy Toimil, vice president of operations at Feeney.
How little maintenance do solar arrays require? Unless an organization is located next to a concrete plant and has to deal with the dust of production, or unless wet autumn weather routinely plasters leaves on the panels, little to no module maintenance is required.
"In most regions the panels are cleaned via Mother Nature," says Scott Shively, principal with the DLR Group.
It's easy to know when there's a problem with the systems. That's because the amount of electricity produced by the modules is often monitored in real-time, and most facility managers can track production on their computers.
"If a system is not producing, it is known almost immediately and maintenance crews can be sent out," say Shively. His firm designed the solar arrays at FedEx Field, home to the Washington Redskins. The design uses 8,000 solar panels that also provide covered parking in an 841-car lot, plus 10 electric vehicle-charging stations. The system can generate 11 percent of the facility's power requirements on game days, and all power needed on non-game days.
As Photovoltaic Costs Fall, Demand for Solar Power Rises
