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Solar Roof

tesla.com

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Re: Solar Roof

#151

Post by j2bax »

dbecker wrote: post #146
blakesterz wrote: post #2

Yikes. I just signed a contract for a new roof here last month, it's going to cost about $12k. Just did the estimate for the Tesla Solar roof... $80,300, so $87k if I want the battery too. I can barely afford the $12 right now, the $80 is just so far over it's not even close, even with how much I save over the years in electricity. That being said, I love these things, so hoping it gets cheaper in the coming years.

The $80k roof is especially scary if you live in an area with any type of natural disaster risk. The area I live in just had a huge hail storm. Most roofs in our neighborhood will require repairs. That's a bummer with asphalt shingles, but it would be a lot worse with an $80k roof. Most people won't think about those risks, but over the time period you need to consider for a roof, it's a big risk in most places.

Tesla claims their shingles are a lot more resilient than standard roofing material...

Re: Solar Roof

#152

Post by blacksmith_tb »

tlb wrote: post #75
IvanK_net wrote: post #45

I have always been a huge fan of a quick transition to sustainable energy sources. There is just one little thing I don't understand. Why they expect people to make electricity at their homes? You can buy a little piece of land in a dessert, put solar panels there and distribute the electricity to other places. And you don't have to climb on any roof during the installation or the maintenance. It is not profitable to…

It's the right question to ask. Home electricity costs around $0.15/kWh, while power plants sell electricity to the grid for around $0.03/kWh. The difference pays for installing and maintaining the grid and local distribution wires to your home. Depending where you are (I live in a forest, where a tree falls on the power lines a few times a year and they have to send out guys in a bucket truck to fix it) it's expensi…

Not necessarily - my home was built in 2013, with a metal roof and 5kW PV system. But because it's so efficient, I end up not just zeroing out my bill, but giving power to the grid for free (since I don't actually get paid for the power I generate, I just get credits). I have evened the odds out now to some degree with a plug-in hybrid, but I will have to see if in practice charging it will soak up some or all of the surplus I was losing...

Re: Solar Roof

#153

Post by greglindahl »

quizme2000 wrote: post #92

I think Elon got ripped off on his last shingle roof. The bar chart is nice but off by at least 150%. I've had many roofing subcontractors as clients past and present in Northern California. Based on an average of 870 roofs in 2016 for Single Family Residential homes in the bay area, Asphalt shingle roofs are $3.12 per square foot for materials and labor. The highest was $5.75 psf and the lowest $2.35 psf. Note that…

The roof launch event was very clear that this is a product that competes against premium roofs. Asphalt shingle roofs aren't premium roofs. As an example, for high-end housing developments, many of them do not allow asphalt shingle roofs.

If that's not your thing, great. Then this isn't the product for you.

Re: Solar Roof

#154

Post by semi-extrinsic »

palakchokshi wrote: post #133
semi-extrinsic wrote: post #106

Earlier quoted context omitted.

I don't understand "income from cars" - do you mean as autonomous taxis? Pretty sure you need to then take into account increased insurance, maintenance costs as well as taxes on that income. Also if this autonomous taxi thing becomes a highly profitable gig (as you suggest), you'll quickly run into a big supply/demand problem. There's only a finite number of people who need mid-day cab rides.

Actually by the time full autopilot is acceptable insurance will actually go down since data will support that in full autopilot the probability of accident is lower than human driving. Maintenance costs on an electric self driving car will actually be lower than a traditional car [1] You are correct though that the income will have taxes applied to it. [1] http://insideevs.com/ev-vs-ice-maintenance-the-first-100000-…

Maintenance costs might be lower for EVs, although as someone who gets his hands dirty on his ICE car I doubt it's going to be significant; most of the time I'm fixing stuff EVs also have (brakes, suspension, sensors, tires, paint damage, lights, wiper blades and fluid, trunk gas struts, indicator stalk, washing the car etc.). I'm also hearing from colleagues of decreased lifetime esp. on brakes of EVs since they get used too infrequently because of regenerative braking, so they get stuck due to rust.

But my point wasn't that but this: using your EV as a taxi will increase maintenance costs (and depreciation) vs. leaving it in the garage.

Re: Solar Roof

#155

Post by ianai »

pedrocr wrote: post #44
atourgates wrote: post #31

Earlier quoted context omitted.

I don't really see the selling point, or value here. Tesla's calculator estimates $40,500 for a roof that generates half our power needs, and should provide $20,400 worth of energy over 30-years. Add in a PowerWall and federal tax credit, and I'm still losing $15,400 over 30-years. If I put that same $40,000 in an index fund that got the stock market's historical 7% average, and waited 30 years, I'd have $308,000. To…

>If I put that same $40,000 in an index fund that got the stock market's historical 7% average, and waited 30 years, I'd have $308,000. Are you doing the math all in present dollars? Because the return is 7% after inflation but >10% before. So you'd have >500.000 in 2047 dollars. In this case it's important to do that adjustment because you're doing an investment upfront for payoffs over 30 years so the value of mone…

A 7% yield is an overly optimistic number.

Re: Solar Roof

#156

Post by greglindahl »

canterburry wrote: post #149
greglindahl wrote: post #111

Earlier quoted context omitted.

Cite? Tesla (at the product launch) actually said it was about as much as buying a new, premium roof + electricity.

Exactly...cost was supposed to be a new premium roof (just the roof, no solar panels) and they are about 3 times more expensive than "just the roof". Unless they meant a "new roof" as in when you build a house from scratch and you don't have rafters or anything. If you have an existing roof you are redoing every 20 years or so, then this is definitely not the cost of a "new roof". So, which "new roof" are we talking…

Sorry, where'd you get a quote for, say, a "Spanish" tile roof that inexpensive? And yeah, he did say (in the launch video) that the electricity was a part of the computation.

Re: Solar Roof

#157

Post by ianai »

pyoung wrote: post #55
tzs wrote: post #40

Earlier quoted context omitted.

> Tesla's calculator estimates $40,500 for a roof that generates half our power needs, and should provide $20,400 worth of energy over 30-years. This depends quite strongly on where you are. Your numbers are very close to the ones I get if I use my correct address, which is in the Puget Sound area of Washington State. If I keep everything the same except the address, changing that to one in Merced, California, then i…

They are using Google's Project Sunroof[1] to do the modeling. The tool uses satellite images of your roof to create the estimates, and accounts for orientation, shading from trees, etc... [1] https://www.google.com/get/sunroof

That's amazing. Just seriously amazing.

Re: Solar Roof

#158

Post by sbov »

ricardobeat wrote: post #66
blakesterz wrote: post #2

Yikes. I just signed a contract for a new roof here last month, it's going to cost about $12k. Just did the estimate for the Tesla Solar roof... $80,300, so $87k if I want the battery too. I can barely afford the $12 right now, the $80 is just so far over it's not even close, even with how much I save over the years in electricity. That being said, I love these things, so hoping it gets cheaper in the coming years.

How on earth did you hit 80k? Using the calculator, the roof for a two-story 3000sqft home comes down to $50-60k, with a net gain of $5k. If your house is any larger than that, $80k is pocket change.

> two-story

Not everyone has a two story house. My parents live in a single story 2k square foot home and tesla estimates the cost to be $69k. I live in a 2 story house with more groundfloor space than 2nd story, and it estimates the cost at $60k

Re: Solar Roof

#159

Post by altano »

"Your Solar Roof can generate $123,900 of energy over 30 years."

Why doesn't the calculator tell me the estimated kWh production instead of a dollar figure that means nothing to me?

Re: Solar Roof

#160

Post by ianai »

taneq wrote: post #80
atourgates wrote: post #31

Earlier quoted context omitted.

I don't really see the selling point, or value here. Tesla's calculator estimates $40,500 for a roof that generates half our power needs, and should provide $20,400 worth of energy over 30-years. Add in a PowerWall and federal tax credit, and I'm still losing $15,400 over 30-years. If I put that same $40,000 in an index fund that got the stock market's historical 7% average, and waited 30 years, I'd have $308,000. To…

Wait what, their estimated payback time is 60 YEARS? This is terrible. They've gotta be just trying to snipe rich early-adopter-for-the-status types.

I'm thinking it's early adopters and new buildings. The Tesla roof on a newly built home may make more sense than a retrofit.
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