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Tesla’s new Solar Roof costs less than a new roof plus solar panels

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Re: Tesla’s new Solar Roof costs less than a new roof plus solar panels

#231

> And we’re actually going to have […] ‘installathons,’ ” Musk said, which will pit two teams against each other to see who can roof one of two similar-sized/designed roofs faster. Musk reiterated later that there’s “quite a bit of R&D just in the installation process itself.” Not a short seller, but that sounds a lot like: “We don’t yet know how to do this well, but in the meantime we are going to optimize for speed…

He prioritizes speed apparently at the cost of anything else. I wonder why he feels such urgency?

I mean yeah he finally got a profit out of Tesla last quarter. But there’s really no tolerance for hiccups in a roof install.

Re: Tesla’s new Solar Roof costs less than a new roof plus solar panels

#232

Earlier quoted context omitted.

Definitely, the solar price in that article is twice what I paid for my 9.4KW system. I wouldn't have gotten Tesla anyway, even if it was cheaper. This is not the sort of place I'm willing to be an early adopter - once they have proven they have decades of experience, like SMA and others, then maybe. Until then, no way.

Decades of experience are a bit much to ask when the market didn't even even exist 19 years ago.

The house I lived in during the late 90s definitely had solar panels, and had for a while.

Re: Tesla’s new Solar Roof costs less than a new roof plus solar panels

#233
post #89

Earlier quoted context omitted.

You could reshingle a roof for $3.50/sqft and it's not unheard of to get traditional solar installed at $1.50/W, ~$15,000 for a 10kw system. $7000 + $15,000 Then you apply the federal credit after that. This is for a grid-tie system, I don't think Tesla is pricing theirs with a powerwall here. Edit: apparently they're pricing it with 2 powerwalls, still cheaper by a sizeable margin however.

I just put in a 12kw system. It was $32k before federal rebate, and it was the cheapest bid by 5 different contractors. Not sure where your getting $15k

Wow, that seems quite high. Panels are around $0.50/Wh. Add in another $2000 in materials and labor cost $24k!

Re: Tesla’s new Solar Roof costs less than a new roof plus solar panels

#234

Earlier quoted context omitted.

The trouble is that you're necessarily picking winners and losers in order to design the incentive scheme. It makes no sense to pay somebody $7500 to buy a new car to drive to work, but not to switch to cycling or telecommuting. In this case, it's not necessarily clear that this is a product that needs to happen. Grid scale solar is significantly cheaper due to the economies of scale. Were there a carbon tax, there'd…

That's exactly what regulation is and does. It picks winners, picks harmful phenomenon, and acts accordingly, with a short-to-medium timeframe based on what would get the most votes. I, too, believe that taxing actual atmospheric carbon impact would be great, but how would you measure such a thing fairly?

>That's exactly what regulation is and does. It picks winners, picks harmful phenomenon, and acts accordingly, with a short-to-medium timeframe based on what would get the most votes.

The subsidies are terrible. They are way too narrow and don’t address the root cause of the issue. Climate change is not happening because we don’t have enough renewables, climate change is happening because our GHG emissions are too high.

Tax the emissions and all activities which generate emissions become less appealing, while all opportunities to reduce the emissions become more lucrative. The example of riding a bike instead of buying an EV fits into this as well. With a carbon tax, using a bike would be equally accounted for.

By using subsidies, the government gets to pick the winner and doesn’t let people think. Renewables especially as they are now are a terrible way to tackle the problem. If we used taxes instead of subsidies, I’m afraid that not many renewable power plants would be built, because other alternatives are way more effective at curbing emissions.

Solutions like rooftop solar – and by extension, these Tesla tiles - wouldn’t make a lot of financial sense if people were billed for their electricity appropriately based on costs. The cost of electricity distribution is primarily a fixed cost in the infrastructure and its upkeep. The variable cost of generating the electricity is small in comparison. People, however, are generally billed more in variable cost based on use of electricity rather than with a larger, fixed fee. It’s set up in this way because it makes sense; the poor can afford connecting themselves to the grid and keep the necessities powered, while reckless use of energy i.e. having AC on 24/7 is disincentivized by the cost.

But once people start pushing rooftop solar on their grid and selling the energy back to the grid at the retail price, not the wholesale price, they are being massively subsidized in their electricity generation, as part of the fixed cost of operating the grid was baked into the variable cost of electricity prices. The pushback from utilities comes from exactly this perspective; if more and more people start net-metering their own bills lower with the rooftop solar, then it means that fewer and fewer people will be responsible for appropriately funding the grid.

In an extreme scenario where everyone net-metered their bills down to zero, it would mean that nobody would be paying for the grid. Obviously, such a situation is unsustainable. And even though there’d be plenty of solar to go by in such a situation, the grid would still be a necessity, as is all the generation which functions as a back-up. And somehow, it would all still need to be paid for.

But there’s more to it, too. Net-metering creates a reverse-incentive. Electricity prices in the wholesale market can even go negative if there is overgeneration, because overgeneration is harmful, and it needs to be dealt with. If net-metering practices are in place, and people start doing more and more rooftop solar to the point of more and more frequent overgeneration, the costs of operating the grid go up. Consequently, so would price of electricity. With a net-metering scheme still in place, everyone else is further incentivized to build solar panels on their roof and do the same to avoid paying the high prices.

If the compensation for the electricity fed back into the grid was based on wholesale price instead, then, once average price (and value) of solar-generated electricity goes down, so do the incentives to build more solar panels.

Adding insult to injury, the back-up issue is generally solved by using gas-fired power generation, as batteries cannot address the issue at this scale. Batteries are useful for bridging the gaps in between switching power generation sources, but the kind of quantity of capacity you’d need for a battery-only backup solution is not feasible.

For back-up, gas is the primary back-up solution in California as well as in Australia, and the Russians are building a pipe to supply Germany. Ironically this makes solar generation - when the whole power generation solution is inspected at the grid-level - not all that green. And while this aspect of solar is ignored by subsidies, a carbon tax would still take it into account.

The point being, subsidies can not only be ineffective, they can also be counterproductive in addition to ignoring all the alternatives.

> I, too, believe that taxing actual atmospheric carbon impact would be great, but how would you measure such a thing fairly?

You can measure emissions at sources and impose heavy fines on anyone who tries to circumvent them. The common problem in globalization, though, is defining and applying these standards universally and fairly. If you can’t trust the Germans to not fumble their numbers, what you’d think would happen in some other countries? Still, with a coordinated effort and systems to ensure transparency, it would be possible.

Another method would be to subsidize more effective alternatives or for the government to build the more effective solutions by themselves. While this wouldn’t have the direction-changing impact of the carbon tax, it would be more straightforward to implement without the requirement of tracking pollution. Targets of subsidies could be selected by their impact on emissions per $ invested. Of course, the numbers could be fumbled here as well, but at least the calculations could be made public and be subject to scrutiny.

Re: Tesla’s new Solar Roof costs less than a new roof plus solar panels

#235

> It also lists $33,950 as the price after an $8,550 federal tax incentive. There is something absolutely astonishing about the fact that in America the way we have go about being eco-friendly is to give huge tax breaks to rich people to buy solar panels and electric vehicles. To think with all that money we could build better infrastructure and denser housing. Really boggles the mind.

Those same incentives put a new Model 3 at $31,000 [0]. The entry level Toyota Camry is $24,000. You'll save $700-$1,200/year on 'energy' with the Tesla, save on oil changes and brakes and the Model 3 costs less to own than the Camry in maybe 7 years. Reduce pollution, avoid gas stations, have a lot more fun driving the safer Model 3. Electric cars are not just for the rich any more. [0] https://www.tesla.com/model3/…

Depends a lot of locale. Where I live, in local dollars, an entry level Camry is is $24,295 (or $28,250 for a hybrid) while a Model 3 is $50,990 after incentives.

Also not sure about a Model 3 being safer than a Camry, they weigh a similar amount and are both IIHS TSP+. (And a hybrid Camry weighs close to 1000 lb more than a Model 3.)

Re: Tesla’s new Solar Roof costs less than a new roof plus solar panels

#236

Earlier quoted context omitted.

> solar needs the grid to be even close to viable This was true 20 years ago and will be laughable 20 years from now. > The only power generators that can do that are ones that burn fossil fuels. Fossil fuel generators do NOT ramp up and down quickly. BTM and FTM battery storage solutions ramp up and down faster and are rapidly becoming cheaper and more environmentally friendly alternatives. > energy use in building…

>This was true 20 years ago and will be laughable 20 years from now. Will the sun start shining at night in 20 years? >Fossil fuel generators do NOT ramp up and down quickly. Natural gas ramps as quickly as it can. But let's assume that's true, that's not a point against me, it's a point against solar because then it means that solar is completely unworkable. >Every one of these supposed drawbacks of solar also apply…

> Natural gas ramps as quickly as it can. But let's assume that's true, that's not a point against me, it's a point against solar because then it means that solar is completely unworkable.

You're thinking about this wrong. If you want 100% generation from solar then you need a ton of storage, period. But who says it has to be 100% solar or 0?

Take a look at the daily electricity demand curve. Lower at night, higher during the day. The (large) difference between the nighttime demand and the daytime demand? That's what you use solar for. Even if batteries are completely off the table, solar is still useful for that. And in that case your natural gas plants only have to run for a couple of hours between sunset and bedtime instead of all day long.

We don't know if storage technologies are ever going to be cost effective enough to use 100% solar day and night. They're not right now, but they're also declining in price. If they get there, well, that's the end of the matter. If not, you use nuclear at night, supplement it with solar during the day and, in the long term, suffer the high cost of batteries for a couple hours around dusk, which is still a whole lot cheaper than needing enough of them to get you through the whole night.

But you have a significant amount of solar in every case. And it can also take on close to 100% of the new load from charging electric vehicles simply by charging them while the sun is out.

Re: Tesla’s new Solar Roof costs less than a new roof plus solar panels

#237
post #213

Earlier quoted context omitted.

So, should we expect the Tesla roof, which has historically had so many issues that they’ve done very few installations, to suddenly be able to last 50 years?

What issues? They did very few installations of previous iterations because they took a long time to install, thus were expensive. Doesn't mean there were any quality issues

https://www.businessinsider.com/tesla-solar-panel-fires-beco...

Re: Tesla’s new Solar Roof costs less than a new roof plus solar panels

#238
post #27

Earlier quoted context omitted.

In the US roofs last more like 25 to 30 years for shingles.

The manufacturer states 25-30 years for shingles, but it's rarely the case they actually last that long unless you're paying for premium shingles. I'm in Canada though, so perhaps the harsher weather has something to do with that. Regardless, in Canada at least, 25-30 years for shingles is not common; 15-20 is more realistic from what I can tell in my area.

GAF has a 50 year warranty on its shingles. People who are talking about failures after 10-20 years are buying cut rate product and having it installed shabbily.

https://www.gaf.com/en-us/document-library/documents/product...

Re: Tesla’s new Solar Roof costs less than a new roof plus solar panels

#240

Earlier quoted context omitted.

If you shop around it's abundantly clear that the price of a new roof varies wildly. Some of it is materials. The guy offering 50 year warranty GAF super-premium install who spots loads of potential problems up front and factors them into the cost is going to run much higher. The guy who is just going to hire some rando non-english speaking guys from the 7-11 and toss on the cheapest possible materials without concer…

> The guy who is just going to hire some rando non-english speaking guys from the 7-11 and toss on the cheapest possible materials without concern about the underlying structure is going to be like a 1/4 of that price. You’ve met my guy Serge! He’s actually quite good and I’ve used him on two different houses. He probably has twice the experience of the super premium guy in town. It’s mostly nailing rocky tar sheets…

They might be good, they might not. It's a luck of the draw when you are hiring the guys just standing on the street corner the morning of the install.

Contractors that have their own dedicated install crews cost more, but are much more reliable.

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