Credit: Joseph Rey Au

It would be logical to think that the first step in specifying and installing photovoltaic (PV) panels on a remodeling job would involve getting the right orientation for the panels — optimally, that would be due south — but the real work actually starts inside the home, not outside.

The first step is to lower the energy use of the existing structure. “We always start the work with a client by cutting down on electrical needs,” says Dennis Allen, president of Allen Associates, in Santa Barbara, Calif. That means reducing a home’s energy requirements with extra insulation, better windows, high-efficiency LED lights, and wrapping the attic with a radiant barrier to reduce solar heat gain.

The second step has its own mantra: location, location, location.

“The general rule of thumb is within 30 degrees of south,” says Millard Blakey of WreckCreations, in Lexington, Ky., who installed Sanyo panels at his own home in 2007. “The closer you can get to due south the better,” he says. “There’s a slight percentage of less energy the further you get off due south.”

Embracing the Panel

In Blakey’s case, the front of his roof — often a typical location for PV panels — was at the extreme edge of south. Plus, because rooftop panels “haven’t quite been embraced” in his part of the country, Blakey wanted to disguise their location. His solution was to specify semi-transparent panels to top a trellis-like backyard deck cover angled to the south to capture the sun. “Typically, PV panels are black on the underside, but since ours are semi-transparent, you can see through them,” Blakey says.

When installing the panels, “you want to make sure they’re attached firmly to whatever surface you’re using, with as little obstruction as possible,” Blakey says. “They’re fairly easy to install. What’s harder is getting the cabling back to the electrical panels in the house.”

For one remodeling project, Allen Associates’ installation of three different Sharp PV systems (for heating a pool, providing domestic hot water, and generating electricity) was handled by California Solar, an experienced trade contractor. “They do the installation and handle all the paperwork for credits and rebates,” Allen says. Blakey says he also knows a number of excellent contractors “who have been doing this sort of thing for 25 years,” and he relies on their expertise.

Kathleen Stanley is a freelance writer in Washington D.C.