A Tesla solar roof will also lose some of the energy-generating density of a traditional panel, because the cells must be spaced farther apart to account for the edges of the tiles, BNEF’s Bromley said. Therefore, the percentage of the roof that will be covered by active solar cells will be higher, as will the total cost of the roof. All told, a traditional solar setup might be 30 percent cheaper than a Tesla roof, he said, but Tesla’s will look better and come with a lifetime warranty. “A 30 percent premium could well be acceptable.”
“It is the most affordable roof you can buy, all things considered,” said Peter Rive, co-founder of Tesla’s recently acquired SolarCity division.
Perhaps the extra cost is worth it in terms of getting a new roof and possibly not having the visual impacts of a traditional solar array (I personally don’t mind the look of traditional solar panels, but some people do, which could decrease home values I suppose). But only so many homes need a new roof at a given time, so right away the market seems limited.
There also may be technical issues with this new type of technology. I talked to a solar engineer recently who thought the tiles would have problems without having the cooling air space underneath, like with traditional mounted panels. The extra heat would supposedly hinder the lifespan and energy production value. I don’t know how to evaluate that claim or whether or not Tesla has addressed it, but it points to concerns people may have with adopting a new form of the technology.
I like the idea of Tesla combining with SolarCity to package clean energy and energy storage together with the vehicles, but the solar roof concept may have a rocky start.