The solar roof could finally become a reality thanks to GAF’s nailable solar shingles

In 2016, Tesla tried to reinvent the humble roof as a beautiful array of glass tiles brimming with solar energy — a vision it’s been struggling to deliver ever since. But San Jose, California-based GAF Energy thinks it has a simpler solution to the solar roof. It’s built a solar shingle, one that can be nailed down in packs much like the everyday shingles you’d use when repairing or replacing your roof.

You might have heard of solar shingles before, but GAF Energy president Martin DeBono suggests the new Timberline Solar shingles are the first to actually deserve that name because they’re the first to actually work that way — you literally drive nails through a three-inch nailing strip, overlap the top of that shingle with the bottom of the next one, and repeat. “A number of companies have come out with what they call solar shingles, but they’re pretty much identical to regular solar panels, just small,” explains DeBono, saying how those previous solar roofs also required rails so the panels could be screwed down.

The result of true shingles, DeBono claims, is that it takes days instead of weeks to install a solar roof. “We’ve installed them already in two days, including ripping off the old roof and putting on the new roof,” he says. The company already tried traditional tile-based solar roofs, pointing me to a previous interview where DeBono said GAF Energy had installed over 2,000 of them, allegedly more than Tesla. “It takes multiple days, 10 to 12 people on the roof,” DeBono relates. But its parent company, building materials conglomerate Standard Industries, decided to invest over $1 billion in this seemingly simpler shingle solution instead. (Here’s a Forbes profile of Standard Industries’ founders and their solar play.)

DeBono says the Timberline Solar are the first products to ever receive UL’s 7103 certification to serve as both solar panels and construction materials, thanks to a special sandwich of glass, polysilicon solar cells, and top layer of a proprietary fluorinated alkane ethylene polymer that’s fire-resistant, impact-resistant, textured to be walkable, and still transparent enough to let the light through. He says they give the panels a Class A fire rating, stand up to hail, and yet the shingles are actually less dense at the same thickness as a normal shingle, meaning they weigh slightly less and should be just as easy for roofers to sling around.

Image: GAF Energy

And while it takes a lot more solar shingles than solar panels to form a roof — an average-sized 6kW array might take up 130 of them — DeBono says it shouldn’t be less efficient or more costly just because there are more modules. For one thing, DeBono says the Thai cells his company is using are 22.6 percent efficient, within a few percent of the state-of-the-art in solar panels, and the greater number of shingles means the system’s total power doesn’t degrade as much when some of them get shaded as the sun moves and the weather turns.

For another, that 6kW system should take up between 350 and 450 square feet on a roof, roughly the same amount of space as a rack-mounted solar panel system, and the rest of the roof can be filled in with matched shingles from GAF.

Image: GAF Energy

But, like other solar roofs, it’ll definitely cost more than simply adding solar panels to an existing known-good roof. “It will cost the same as if you were to get a new roof and put solar on it,” says DeBono. (He declined to say how much each individual shingle costs.) But because a lot more people are getting new roofs each year than are adding solar — 5 million a year vs. 300,000 a year, he suggests — there’s a big opportunity for some of those people to add integrated renewable energy while they’re at it. Particularly since GAF already sells traditional shingles to cover one out of every four of those roofs, the company claims.

The solar shingles don’t look exactly like shingles, of course — there are covers for their wiring (for easier maintenance than having to remove the entire tile, says DeBono), and you’ll need a mid-circuit interrupt safety device for every 2kW of panel that fits in a visible box (though DeBono says you could put those in the attic instead of atop the roof).

GAF Energy is currently making all of these in a 130,000 square foot facility in San Jose, California, with a capacity of roughly 50 megawatts per year. That isn’t as tremendous an amount as it might sound — it’s a little over 8,300 homes per year if you assume each of them requires the average 6kW array. But DeBono says he’s also looking at it as just GAF Energy’s first manufacturing facility, with more potentially on the way.

He says the new Timberline Solar panels are available now via sister company GAF’s existing network of roofing contractors across the US East Coast and Texas — though not in big solar states California or Florida quite yet. He says it’ll take roughly 90 days for them to be listed with the California Energy Commission and possibly four to five months for additional wind testing in Florida and will expand from there.

GAF Energy actually moved its solar manufacturing to California just this past year, and the timing isn’t all great: the solar industry is currently fighting against a new California proposal to charge solar panel owners a flat fee for every kW of solar panel capacity they hook up to the grid, in addition to other reduced incentives for installing solar. “What has been proposed would be the death of the solar industry in California, and that’s not hyperbole,” DeBono tells The Verge, pointing to what happened to the Nevada solar industry after that state phased out incentives and how the state eventually changed its tune.