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Elon Musk: Tesla's Solar Roof Will Cost Less Than a Traditional Roof (bloomberg.com)
An anonymous reader quotes a report from Bloomberg: After Tesla shareholders approved the acquisition of SolarCity, the new company is now an unequivocal sun-to-vehicle energy firm. And Chief Executive Officer Elon Musk didn't take long to make his first big announcement as head of this new enterprise. Minutes after shareholders approved the deal -- about 85 percent of them voted yes -- Musk told the crowd that he had just returned from a meeting with his new solar engineering team. Tesla's new solar roof product, he proclaimed, will actually cost less to manufacture and install than a traditional roof -- even before savings from the power bill. "Electricity," Musk said, "is just a bonus." If Musk's claims prove true, this could be a real turning point in the evolution of solar power. The rooftop shingles he unveiled just a few weeks ago are something to behold: They're made of textured glass and are virtually indistinguishable from high-end roofing products. They also transform light into power for your home and your electric car. "So the basic proposition will be: Would you like a roof that looks better than a normal roof, lasts twice as long, costs less and -- by the way -- generates electricity?" Musk said. "Why would you get anything else?" Much of the cost savings Musk is anticipating comes from shipping the materials. Traditional roofing materials are brittle, heavy, and bulky. Shipping costs are high, as is the quantity lost to breakage. The new tempered-glass roof tiles, engineered in Tesla's new automotive and solar glass division, weigh as little as a fifth of current products and are considerably easier to ship, Musk said.
If Musk is correct then... Great! Sign me up!
I think I'll wait for a variety of third party reviews before I get too eager though. Of course Musk is going to cheer his own product, but lets see if experts agree with him and if the price really is lower when it really hits the market.
"That's the way to do it" - Punch
Including the PV cells? Excluding the generated electricity benefit? Color me suspicious. I'd really like to see that. Mass-produced conventional solar panels (just the hardware on pallets) are still about twice as expensive as my most recent roof (including installation), per unit of area.
Ezekiel 23:20
I keep forgetting that there are places in the world that aren't California. Out there, "traditional roofing materials" are asphalt shingles, or sometimes cedar shakes, neither of which is bulky or brittle.
See that "Preview" button?
...10 times more expensive to buy for the end users.
When the solar cells dropped in price from the hefty China manufacturing of these, people in Sweden tried to purchase a lot of these, then a heftyn anti-dumping 60% import tax "to protect other producers of panels" where quickly introduced to stop this "green madness", hah...
But good on him for trying, now if the governments of the worlds would like to dance to that tune, we'd all be in the green, but I can pretty much promise you, the ones earning $$$ on something else won't have it!
What this world is coming to - is for you and me to decide.
It sounds like if you read between the lines (as you always have to do) they are comparing them to high end roofing materials like terra cotta and slate, which cost 20x more than asphalt shingles and are fragile. People who can afford this type of roofing aren't trying to cut their electric bill.
Calm down there Mr. Free Bitcoin. If you think Musk "got lucky" by investing in PayPal, "got lucky" again when starting Tesla at just the right time, "got lucky" again by pushing the private space sector again at just the right time, and "got lucky" by building in Solar City to vertically integrate two of his biggest (and most environmentally impactful) industries, then I suppose he is just an insanely lucky man. Taking a step back and looking at the bigger picture, though, one might call him a visionary. Yes, having the right people is critical. Steve Jobs was neither a hardware nor software engineer, he was a visionary.
They have some impressive impact test videos. Tempered glass is amazingly tough. Now, if you manage to break it, it breaks in its entirity (aka, an entire shingle), usually into little bits. But that break takes a pretty severe impact.
Time will tell what the total cost is in the real world, of course. My questions are more concerning how fast real-world installs go, aka what the labour costs are like.
Wingus, Dingus! Listen up!
I didn't read TFA
That's obvious. If you had, you'd have noticed that they're comparing the price to terra cotta and slate roofs, not "impermeable sheats of $SOMETHING", and those materials are bulky, heavy, fragile and expensive.
Tesla's new solar roof product, he proclaimed, will actually cost less to manufacture and install than a traditional roof -- even before savings from the power bill.
Unlikely that it will be cheaper than an asphalt shingle roof. Not so surprising that it might be cheaper than an (expensive) slate or similar high end tile.
They're made of textured glass and are virtually indistinguishable from high-end roofing products
Umm, no. They are not "indistinguishable" from high end roofing products but they are reminiscent of them and appear to be rather attractive looking on their own merits.
Your concerns about tornadoes and cold weather and snow loading - these are things off the top of your head that you thought of within 5 minutes of skimming the article. I'm pretty certain the engineers - who spend their entire days working on this project - have thought of all of this.
That being said though, I'm with you. I would wait for a third party review as well. Let's get some objective pricing and usage data before we get too happy.
Weaselmancer
rediculous.
No problem, just reverse the polarity and they'll consume electricity and emit a warm glow and melt off all that snow.
This seems like a no-brainer, but it also seems silly to put these on north-facing or shaded roofs. It would be nice if there were cheaper, non-PV versions to cover the portions of my roof that aren't going to generate appreciable power. A consistent appearance in the roof, but only pay for the PV where it makes sense.
I guess maybe having two different versions would potentially make both more expensive.
"Open the pod by doors, Hal" > "I'm afraid I can't do that, Dave" sudo "Open the pod bay doors, Hal" > alright
A single clay roof tile costs the equivalent of $0.5 where I live. It's good for half a century, no problem.
I have 5 places that produce clay building bricks and clay roof tiles in a radius of 150 km to choose from.
Transportation is cheap, and even if some tiles/bricks break in transport, they're so cheap that... well, nobody cares if there's a 1% loss in material.
What makes entepreneurs successful is not luck, but taking advantage of it when it presents itself.
If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
Re, a rake: Absolutely would not break, unless you put the rake handle-down on a shingle and hit the other end with a sledgehammer. Tempered glass is far too strong for that. Scratching - steel is 4-4,5 on the mohs scale, glass is 5,5. That said, you can still sometimes scratch glass with steel if you concentrate enough force onto a small enough point. Seriously doubt a rake will, however.
Also, note that it's not like small scratches stop a solar cell from working.
Wingus, Dingus! Listen up!
Because like the rest of their houses they are generally not built to last. They use asphalt shingles which is basically cut up flat roofing material. Something that would only be considered for a shed or garage in Europe.
It's probably a got something to do with the rapid build out of America during colonization. Remember ~40% of housing in the UK was built before the second world war and generally we expect the house we live in to be there long after we are dead and buried which as far as I can make out is not the case in the USA. We go for traditional brick built will stand a couple hundred years at least houses.
They're complete morons if they've designed a roofing product and haven't conducted freeze-thaw tests. Literally sued-off-the-market level morons. I doubt they could even get it certified as a roofing material if they didn't.
Wingus, Dingus! Listen up!
When a photovoltaic cell collects energy from a Photon, is does not absorb the whole photon, it only increases it's wavelength and re-emits it; basically converting regular light into infrared light.
While the regular light bouncing of a simple white roof could leave the atmosphere, taking it's excess energy with it, the now infrared light gets trapped by the greenhouse effect, heating the atmosphere.
It's 'free' electricity for the owner, excess heat for everyone else.
Are you sure? Let me check my windows...
Yep, still there after decades of winter/summer cycles.
Carry on.
Take a look at this wikipedia page.
https://en.wikipedia.org/wiki/...
Pay attention to the picture of the earth with some little black dots on it. That area of the dots is enough to meet the worlds 18TW total energy needs from solar.
The idea that there is not enough solar energy to meet the worlds total energy needs is just ignorant.
The video test shows the weight hitting dead center, making a clear mark- probably a crack in the tile. In addition, the tile was not held down- it was allowed to bounce up, releasing some of the energy- it wasn't a test representative of reality.. Affixed to the roof, the energy of the dropping object has to go somewhere. Furthermore, in a hailstorm- the hail will be hitting *everywhere* on the tile, not just in the center, but on the edges. I've been through a hailstorm with hail that was easily golf-ball sized. My roof (asphalt shngle) was a total loss, plus my cars all had major damage, including having to replace windshields.
All that said, I like the idea, and if Tesla is willing to warranty it against hail, I'll sign up./p?
Also: are rake tines even steel anymore, or are they aluminum (even softer than steel)?
Also, about the previous comment: tool steels are a lot harder than mild steels and are much easier to scratch glass with. But you'd never make a rake out of a tool steel.
Wingus, Dingus! Listen up!
You don't see that many large glass surfaces around for a pretty good reason...
You mean except for almost every window on every house and car made? [sarcasm] Yeah barely any glass out there. Who would use glass? [/sarcasm]
I am actually kind of disappointed that Tesla is throwing their lot in with Solar City. Their sales people positively infest all of the Home Depots around here (Boston, MA). They are extremely pushy and act like you are the asshole for wanting to just shop instead of listen to their sales pitch. Any company that employs those kinds of sales tactics doesn't inspire a lot of confidence in me, and I plan to never do business with them. I was planning to consider a Tesla for my next car, but this deal is making me reconsider.
Uhhhh, how much glass is used for horizontal (or horizontal-ish) surfaces?
Quite a lot. Open up your refrigerator and chances are you'll see a rather large load bearing glass surface. Look at atriums of commercial buildings with glass roofs. Look at greenhouses. Glass table tops. Check out the sunroofs in cars. There are glass walkways.
Horizontal glass surfaces are all over the place if you actually bother to look for them.
Reading comprehension much? I was not talking about interior surfaces, I was talking about exterior. I will assume that you are genuinely stupid instead of being a troll...
Do you see a lot of indoor atriums, greenhouses, sunroofs, etc or are you cherry picking to just be a jerk? You seem to be the one lacking in reading comprehension in addition to failing to understand anything about materials science. Glass does not intrinsically equal fragile. It's perfectly possible to design glass surfaces to be quite robust and take a substantial impact.
In case you still don't get the point, glass can literally be bullet proof if you want it to be. Who is the "genuinely stupid" one now?
Shingles, on the other hand, could have hail dropped from a very high distance indeed -- enough to reach terminal velocity. Where I live we had a severe hail storm a couple of months ago. A friend of mine is getting insurance to replace his entire roof.
And that is not a glass roof so what exactly is your point? No practical roofing material is going to be indestructible. Glass tiles can be just as durable as stone ones if not moreso. If you had a clue about materials science you would already know this.