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SolarCity Plans To Release New 'Solar Roof' Product Next Year (computerworld.com)
An anonymous reader writes: SolarCity, the American provider of energy services recently purchased by Tesla Motors for $2.6 billion, is planning to produce a new "solar roof" product next year. Computerworld reports: "Five million roofs are replaced each year in the U.S., so instead of simply swapping out old shingles with new ones, why not turn the whole roof into a solar power generator that's integrated with your home's electrical utility? That is SolarCity's plan for a new product it expects to begin producing next year, according to statements made during the company's second-quarter earnings call last week. During the call, SolarCity Chief Technology Officer Peter Rive alluded to a new product that would be produced at the soon to open Buffalo, N.Y., solar panel manufacturing facility. Then SolarCity co-founder and Chairman Elon Musk interjected and said the product would be a solar roof, 'as opposed to a [solar] module on a roof.' The solar roof also has the advantage that it doesn't 'cannibalize' any existing SolarCity product, such as solar panels installed atop roofs, Musk said." "If your roof is nearing end of life, you definitely don't want to put solar panels on it because you're going to have to replace the roof," Musk said. "So there's a huge market segment that's kind of inaccessible to SolarCity. So, why not have a solar roof that's better in many other ways as well," he continued. "We don't want to turn over all our cards right now, but I think people are going to be really excited about what they'll see."
They have an inversion mode where rather than generate electricity from sunlight, the voltage is reversed and they consume electricity and produce heat. This melts any snow and ice present. Right now this is a manual switchover by the homeowner, but I would expect an optical sensor in the future that detects when the light is being obscured by snow and acts accordingly.
Here in upstate NY, winters often mean that I need to get out our roof rake to pull snow off our roof. If I don't, ice dams form and then runoff from melting snow gets under our roof shingles and can get into our house. My questions for SolarCity would be: Would these solar shingles hold up to having a roof rake scraped across them? (It would be useless if I had to replace shingles every year due to roof raking damage.) Also, how would they handle snow melt getting under the shingles? Presumably, there will be wiring there. Would moisture under the shingles cause issues?
Roofs are designed to prevent ice dams. If you are getting them, then your roof (or attic) needs help. Most likely, you don't have enough insulation in your attic. Ice dams happen because the underside of the snow on the roof is warm enough to melt the snow. That warmth comes from the attic. The attic should be cold enough that the roof material stays cold, and the snow on the roof doesn't melt on the underside.
I used to get ice dams on a home in Michigan. It already had insulation between the joists, but that wasn't enough. Adding a second layer of insulation, perpendicular to the joists, resolved the ice dam issue.
I think the intention is the replace the shingles and have your roof made out of solar panels. I've had this same idea for a long time. There's no benefit of asphalt shingles other than the relatively low cost.
I hate those damn things. We have a low pitched roof and shingles don't last long on them. So it's like every 10 years and new ones. As well, if they aren't laid right, heaven help you. Some asshat replaced them before we bought the place, and had a small place, about an inch square where they didn't cover. Right on a gutter We got a lot of wood rot right there. That was fun to fix.
I wanted to go metal last time we replaced them, but my better half thought metal "looked cheap" However now that we are looking at our third replacement, and she's changed her mind. But these solarpanels? Very interesting indeed.
If you could replace your roof with a solar panel system that #1 protected your home and #2 provided a significant amount of power generation I wonder what the total cost of ownership would be. At current electricity rates, I'll pay about $20,000 over the next 20 years to the electric company. I would also pay $15,000-$20,000 every 20-30 years to get new shingles.
Make certain to do your own calculations, and not rely on people who have a vested interest in you using some other method. I bought a new super high efficiency gas furnace, replacing my oil furnace, 4 years ago - it's already paid for itself. Oil people said it might be 15 years.Same with insulation. I'm spending per year what some friends pay per month in energy.
As well, there are the incalculables. Access to the electricity. We have a lot of power outages in my area. And with the whacked weather, we are sometimes out for a while - one time almost a week. Your own power source can make life a lot nicer. It was nice to have lights and furnace that week. Note I wasn't using solar that week, just another power source.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
Maybe you could rake it with a wide broom or plastic snow rake. Our neighbor has solar panels on his roof and most of the time the snow slides off after the first sun starts to hit it. Unless its overcast for a few days after a snow, it always seemed to melt off quickly. He did use a broom a few times with new snow, but the sun and melting seem to go hand in hand anyway. And there's no need to clear the snow if there's no sun for the solar cells to use.
So, maybe in the case of a 2ft snowfall you could clear it, but that glass does a good job clearing itself anyway.
http://github.com/gbook/nidb
I wanted to go metal last time we replaced them, but my better half thought metal "looked cheap" However now that we are looking at our third replacement, and she's changed her mind.
Off-topic but my father-in-law is a fireman. He's said many times that the best way to ensure total destruction of your home and property in a fire is to have a metal roof.
I'm not an expert, but basically the metal traps all the heat and forces it downward and most firefighters (at least in my area) won't go into a building with a metal roof on it except only to save human life. And, even then, the chances of saving someone are lower.
Just something to think about.