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Solar Roof

tesla.com

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Re: Solar Roof

#121

Post by lutorm »

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…

Speak for yourself. My home electricity costs right around $0.30/kWh. If you can't get a net metering contract, it's already about cost-effective to just go off-grid.

The economic calculation for one of these roofs probably looks very different depending on where you live.

Re: Solar Roof

#122

Post by majormajor »

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.

> 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.

That's hardly pocket change in most of the country, where you can get a lot more sqft/$ (and potentially in a bigger, 1-story footprint) than on the west coast.

Re: Solar Roof

#123

Post by stale2002 »

Scoundreller wrote: post #118
stanmancan wrote: post #102

Earlier quoted context omitted.

And whats wrong with that? A bunch of rich early-adopter-for-the-status types will get a Telsa roof, Telsa will get better at developing the technology and the price will come down, meanwhile more people are moving to renewable energy sources to power their homes which is good for the environment. Whats the downside here?

Through the tax credits, we're all paying for someone else's pet project. Since Tesla's products are expensive, it would be a regressive tax even if we all bought enough solar panels for our needs.

The point of the tax credit is to encourage innovation.

Yes, solar roofs are a bad investment NOW, but they might be a good idea in 20 years, once all these businesses have done this research on them.

Re: Solar Roof

#124

Post by palakchokshi »

stupidhn wrote: post #109
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.

> There's only a finite number of people who need mid-day cab rides. Yeah, it's a contradiction in the business model. Everyone will be able to afford to own a Tesla because everyone will be able to make money from the cars driving everyone around?

There will still be a barrier to owning a Tesla due to the upfront cost of buying one. The fact that it'll be able to pay itself off over time is immaterial to the affordability of at time of purchase.

Re: Solar Roof

#125

Post by euyyn »

mrfusion wrote: post #14

how these shingles connect to each other? And how are they affixed to the roof? You can't just nail them right?

That's what baffles me about this whole thing. Unless your roof is rectangular with homogeneous shadows, if you connect the shingles, say, in rows, you'll have unbalanced voltages. Is the plan to have a microinverter per row of shingles?

Re: Solar Roof

#126

Post by qaq »

To all upset about pricing there are products targeting different income brackets. People in blah also can't understand how we spend half of their monthly income on some organic blah drink. Just because it does not make sense for your particular situation does not mean there is no market.

Re: Solar Roof

#127

Post by timdellinger »

Arcsech wrote: post #119

I'm curious about the durability - I live Colorado Springs, which is typically very sunny (good for solar), but can get pretty bad hailstorms. This means that the average roof lifetime here is much shorter than elsewhere. If the Tesla's roof tiles are actually significantly more durable than asphalt, it could be more cost-effective here than elsewhere.

Also: repairability.

Asphalt shingles are fairly easy to repair once you get up on the roof. Wired stiff solar shingles? That's gonna be more challenging.

Re: Solar Roof

#128

Post by ceejayoz »

atourgates wrote: post #31
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.

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…

> Add in a PowerWall and federal tax credit, and I'm still losing $15,400 over 30-years.

Which you probably sink into a second layer of asphalt shingles 15-20 years in (at least up here in upstate NY where there's plenty of rain/snow). Hopefully it's not a tear-off, as that'll cost more.

Re: Solar Roof

#129

Post by Retric »

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.

It depends on your roof orientation and your location so ROI has a huge range.

For example if you don't have a southern facing roof then this is going to be a terrible investment. However, this is also a home improvement which means a low interest loan which has many tax advantages, remember you pay your electric bill with after tax money but you pay interest on a home loan with pre tax money. Further electricity costs increase with inflation, so your out of pocket investment may be tiny while the value of electricity generated is increasing.

Re: Solar Roof

#130

Post by bluehawk »

vkou wrote: post #108
marcosdumay wrote: post #59

Earlier quoted context omitted.

It's because local photovoltaics can save a lot of infrastructure and can require nearly no labor. You don't buy cold air piped from across the city, you make it locally. Why?

> It's because local photovoltaics can save a lot of infrastructure and can require nearly no labor. No, they don't. You still need almost the entire national power grid to supply your home with night-time electricity... That infrastructure won't be going anywhere. An even worse outcome will be every home having local power storage infrastructure. Tens, or hundreds of thousands of dollars for a power wall, or a compr…

Since we are discussing Tesla solar roofs, they suggest your installation comes with a PowerWall, thereby storing power during the day to use at night. I personally don't think we are there yet, but I think the goal is that you don't need the entire national power grid just for night electricity, just a big battery.
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