As has been widely reported, Elon Musk is making a huge push in solar electricity, forming a conglomerate of electric cars, batteries, and now photovoltaic roofing shingles.
In the finest traditions of Silicon Valley, Musk makes proud declarations about revolutionary technology, and neither acknowledges nor cites any past work in the same area. It is easier to say your stuff is “unique” if you simply ignore everything else!
As I look at their recent splashy announcement about the new solar shingles, I’m a bit worried that we really don’t know what the product really is, or how well it might work.
Home solar power is scarcely uncharted territory, people have been doing it for many decades. It is successful enough that the power utilities and coal barons have been sabotaging it with their “anti freeriding” legislation in Oklahoma and elsewhere.
So what is Tesla offering, and why is it so great?
Basically, the idea is to make shingles that are photovoltaic collectors, so you build PV into the roof, rather than build a roof and then add collectors. This is a great idea, and it has been tried before—without success.
Musk’s devices have the advantage of their own battery technology, but little information has been released about the tiles themselves. They are said to be glass with PV film, and to be more durable that conventional roof tiles. The latter is a rather vague claim (he appears to be comparing to the lowest cost asphalt shingles, not to comparably priced materials), and the former is no different than other solar products (which, by the way, have not been successful).
Exactly what this technology might be has not been published in any form. (I’m a hard liner about the necessity of open, peer reviewed publications.) The unrefereed and un verifiable press announcements claimed that the tiles are highly efficient, with “98 percent of the efficiency of regular panels”. This figure is difficult to achieve with this sort of technology, and many of us would like to see data to back this up.
Even if the tiles are as efficient as stated (which, after all, is no better than a tie with existing technology), they face all the other challenges for home PV installations, including sunlight, local electric rates, and building codes. Musk may assert that these are perfectly good roofing materials, but that doesn’t mean that they will meet local safety codes. Nor does his assertion that they look great mean that people will want them on their house. (And how much does this cost???)
If it is difficult to be sure what the technical merits of Musk’s offering may be, he has two big assets. First, he is abundantly funded, so he has no need to worry about short term financial issues. (It’s way easier to succeed at anything if you have a billion dollars of your own money to play with.)
The second advantage is that he’s got a lot of “sizzle” to sell. You can see this in Darrell Etherington swooning coverage of the announcement (“Why Tesla’s new solar roof tiles and home battery are such a big deal“): everyone is excited by the “Tesla” halo, regardless of whether the product actually is different from other (failed) competitors, or, for that matter, regardless of whether it even exists.
There used to be an ad for Saab automobiles, which included an image of a fighter jet and the tag, ‘If IBM, Boeing and NASA built a car, would you buy it? Of course you would’
Would you buy a solar roof from Tesla motors? A lot of people would, just for the vibe.
Will this be enough to make a large scale success? Who knows. It won’t hurt, that’s for sure.
But home solar is a brutally tough problem, and not everybody cares about the sizzle that Musk is selling.
Would I buy a roof from these guys? Not going to happen any time soon. I have a house, and they aren’t in the retrofit business, yet.
If and when these tiles are available for renovations, it would probably cost the market value of my house to retrofit it with this kind of roof (plus batteries, etc.), and, by the way, the mature trees in the neighborhood will reduce the energy harvest quite a bit.
I’m sure I’m not the only one in such a position.