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Solar Roof

tesla.com

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Re: Solar Roof

#171

Post by SwellJoe »

drozycki wrote: post #78
SwellJoe wrote: post #64

I'm super excited about all of the great stuff happening in solar recently, but whenever I read about the economics of home solar, I'm also always reminded of how stacked the deck is for wealthy people vs. poor folks. There's a very large federal tax credit for solar investment. That's great...but, people who can't afford their own home get no such credit, and there's no way for them to get such a credit. That's a su…

Maybe it would help to think of the credit as benefiting the solar industry more than wealthy people. It's a long road for new tech to reach economies of scale. If society has an interest in reaching that inflection point than the subsidy could be money well spent. Poor people will benefit when the price of the roof falls further; it may never have reached that point without early subsidy. Perhaps it would be more eq…

How about a tax credit for lower power consumption, instead of subsidizing any one path for achieving it?

Re: Solar Roof

#172

Post by fpgaminer »

stupidhn wrote: post #112
fpgaminer wrote: post #35

I'm so absolutely excited for solar power. Tesla's Solar Roof, their PowerWall batteries, electric cars. It's all just painting such a bright future. Certainly Tesla has no monopoly on it, but they've made it sexy and are pushing the bleeding edge forward. Props to them. We recently signed a contract to do an installation on our house (with a local contractor, not SolarCity). It can't happen soon enough! We'll have e…

> All while saving a bucket of money I'd double check my math, because economic law says that's unlikely.

We're paying ~$19.5k for solar panels + installation. After the tax credit, that's $13,650 in cost. We spend ~$960/yr on electricity right now. The solar installation will cover all those needs, plus pay us $711/yr. So we're saving $1,671/yr. Pay off is thus ~8 years. The panels are good for 25 years. That's $28k in savings by the time the warranty runs out. They'll probably last longer.

The batteries are a different matter. I believe net meter makes them irrelevant, so the equation stays the same for most "sane" people. For me, I want to be off-grid, so I'm happy to pay a premium for batteries. That said, SGIP makes them roughly free if we get lucky. We'll see what happens.

Re: Solar Roof

#173

Post by EGreg »

I love their graph, with the solar roof being the only "negative-cost" roof. Really drives the (sales) point home.

Re: Solar Roof

#175

Post by aasarava »

canterburry wrote: post #103
aasarava wrote: post #9

Earlier quoted context omitted.

You got a $12K quote for tile? How long is the warranty? Remember that the 80K quote includes solar, so you'd have to add a standard solar install of the same KW capacity to your initial quote to really compare apples to apples. You'll probably still pay a premium to go with Tesla, but the no-profile solar integration and lifetime warranty really look attractive. Some people are probably willing to pay for it, simila…

No, I just want a new roof. I wasn't planning on installing Solar. Solar was supposed to be a perk of buying the roof from Tesla...and all of this was supposed to cost as much as a roof alone.

Not sure why you got downvoted. But the point is that if you weren't planning on solar in the first place, the long-term economics of a Tesla roof look even better. Your 30-year net cost is $12K + maintenance on the standard roof you got quoted on. Tesla is saying their 30-year net cost is -$50K or -$100K or whatever, to be paid to you in what is essentially credits against your electricity bill.

In either case, you can finance the costs. Given how Solar City usually operates, I imagine they'll roll the costs in a lease or power purchase agreement where you send them a check each month for an amount less than your current electricity bill.

I'm not saying it's the best deal around. You could come away with an even better net total by re-roofing and putting on traditional solar panels. But then you've got an uglier roof, if you care about that sort of thing -- and there are definitely people who do.

Re: Solar Roof

#176

Post by kcorbitt »

Reason077 wrote: post #120
pedrocr wrote: post #44

Earlier quoted context omitted.

>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…

Energy prices, and thus savings, are certain to increase over that 30 years too. Quite likely at a rate exceeding inflation.

Energy prices have been mostly flat relative to inflation for 40 years, and there's a reasonably good chance that they will start dropping appreciably (at least during peak daylight hours) as solar continues to make major inroads.

Re: Solar Roof

#178

Post by owenversteeg »

Holy shit, these comments.

"My cars will make $24,000 per year" (in a comment justifying spending a quarter million dollars on Tesla products)

"People don't understand how we can spend half their monthly income on one organic drink" (in a completely unrelated comment)

"if I buy two Teslas my savings triple!" (another person justifying Tesla's marketing with some creative math)

Sounds like something you'd hear from protesters mocking the 1% but no just another day here on HN.

I've been here (in various incarnations) long enough to say this, so could we try to be just a little bit more self aware? 24k/yr is nearly double the minimum wage. A quarter million dollars is a truly immense amount of money. And buying two cars is a dream for most of America, ignoring the fact that those are two Teslas, which are roughly $70k cars (and no, you can't currently buy any $35k Teslas no matter what Musk's Twitter says.)

Re: Solar Roof

#179

Post by [deleted] »

ctdonath wrote: post #42

People keep overlooking the objective value of not relying on "grid" power sources. Power goes off, your system keeps going. Gasoline supply stops (I've seen that a few times), you can just power your car at home. Your system fails, grid is likely still up to cover. Supply-and-demand takes a sharp turn when supply is actually limited and can/does run out . At that point, having pre-paid for your own uninterrupted off…

[deleted]

Re: Solar Roof

#180

Post by 11thEarlOfMar »

ch4ch4 wrote: post #161
11thEarlOfMar wrote: post #138

In modeling whether this makes sense, I looked at my annual electricity bill, which comes in at about $1,800/year. That's not enough savings opportunity to justify a ~$70,000 roof+batteries. However, when I add 2 electric cars, the savings nearly triple [0]. Instead of buying gasoline, I'll be paying for electricity. At $5,400/year, spending $70,000 starts to make some sense. On the other hand, if I put up ugly panel…

In your calculation, $10/kWh is a bit high... the national average is $0.12/kWh

Corrected (thanks for being kind...)
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