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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

#281

Post by gzer0 »

xwdv wrote: post #135
gzer0 wrote: post #121

Earlier quoted context omitted.

Except that time and time again, it has been shown that it absolutely does not work. "[I]f the income share of the top 20 percent (the rich) increases, then GDP growth actually declines over the medium term, suggesting that the benefits do not trickle down. In contrast, an increase in the income share of the bottom 20 percent (the poor) is associated with higher GDP growth. [1]" [1] https://www.imf.org/en/Publication…

Except you don’t need that much GDP growth if the price of everything is going down, so that argument is flawed.

This does nothing to bolster your claim. Your arguement is moronic.

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

#282

Post by gumby »

gibolt wrote: post #221
gumby wrote: post #215

This looks like any other BIPV roof product -- what makes it different? More importantly: how do they plan to avoid the problems that have plagued BIPV for decades?

I'm not familiar with the existing issues, but likely thorough testing and quick scale. I'd expect tile durability and cable corrosion to be the main issues, which seem solveable.

They don’t seem to have addressed the two worst problems. One is interconnect — which drives the cost of installation and of maintenance too. The second is the bonding of the tile to the roof. Typically panels are mounted away from a surface so there is cooling airflow behind them. These are flush on the roof so heat up which is not only as for your house but dramatically reduces efficiency AND lifetime — which will be much shorter than the life of the tiles themselves.

I haven’t seen any mention that this product brings anything new to the table and I’m sure they would have trumpeted it if so. Basically 2012’s BIPV roof solution AFAICT.

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

#283

Post by Marsymars »

11thEarlOfMar wrote: post #262
Marsymars wrote: post #235

Earlier quoted context omitted.

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.)

Hybrid Camry is 3572 pounds maximum [1] Weight of Model 3 is 3627 minimum up to 4,072 (extended range, extra batteries, which are heavy.) [1] Model 3 has the lowest probability of injury in a crash of any car tested by NHTSA since 2011.[0] [0] https://cleantechnica.com/2019/03/14/tesla-model-3-vs-toyota... [1] Google Camry weight; Model 3 weight

Oops, my mistake on the weight, was looking at gross vehicle weight line rather than curb weight. Thanks for the correction.

Though the NHTSA thing you're citing is specifically what the NHTSA told Tesla they weren't allowed to claim.

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

#284

Post by matt_the_bass »

rco8786 wrote: post #26
aphextron wrote: post #11

Earlier quoted context omitted.

> Cheaper than traditional roof plus solar. I find that really hard to believe. A new roof runs between 5-10k, and a 3kw solar system can be had for ~5k + labor. Even if they are including a power wall in that price it's still pretty steep. Edit: It looks like they are actually quoting a 10kw system with 3 power walls (~40kwH storage) included, which at that point sounds about right at $40k. Still far beyond the reac…

> new roof runs between 5-10k, That is incredibly cheap if so. That would be a roof on a small barn around here.

My last house was a 1400sqft cape. Removal of 2 layers of shingles, building a cricket next to the chimney, new lead flashing around the chimney was $7k. I got quote from multiple contractors for roughly the same price. It really depends on the amount of roof.

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

#285

Post by perl4ever »

Someone1234 wrote: post #35
bArray wrote: post #22

I think a major challenge that is yet to be addressed is the fact that solar panels lose their efficiency over time [1] [2]. Seems like you're looking at 80% of rated efficiency after 20 years - and I'm unsure this includes failures. In the UK a 50+ year old roof is very common - most people expect a house to outlast them without anything but minor repairs. If I were building a house I would want something where it's…

UK roofs are made and ceramic and slate. US roofs are made of asphalt. Mostly because asphalt is inexpensive (particularly due to economies of scale/lack of them on ceramic). Ceramic lasts a lifetime, asphalt can be taken out by one bad hail storm. UK homes are made of brick. US homes are made of fiberboard and inexpensive woods. There's a reason why UK homes have lasted over one hundred years, and most US homes won'…

Well, it would have been a huge waste to build houses to that standard here because they all would have had lead paint! Nobody knew that then, but still. I recently considered buying an old house and ended up with a post-1978 one so I don't have to worry about that.

Also, people mention again and again that people replace houses in Japan even more, and yet it doesn't seem to get the jingoistic juices flowing like criticizing the US.

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

#286

Post by woodandsteel »

This is very good news. It's going to lead to a great many new solar installations that otherwise would not have happened, including in new home construction. And if we are lucky there will be other companies that will develop similar products that are good enough to compete with Tesla.

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

#287

Post by [deleted] »

NeedMoreTea wrote: post #76
bArray wrote: post #22

I think a major challenge that is yet to be addressed is the fact that solar panels lose their efficiency over time [1] [2]. Seems like you're looking at 80% of rated efficiency after 20 years - and I'm unsure this includes failures. In the UK a 50+ year old roof is very common - most people expect a house to outlast them without anything but minor repairs. If I were building a house I would want something where it's…

50 years is almost new. Most 100 year old terracotta tile are still on the original set, and slate often lasts 200. Where roofs are replaced, aside from storm damage, it's most common for that to be down to having got rot in the woodwork than fault with the tile. I suspect a fair few are down to iffy sales tactics from dodgy builders. (i.e. get someone out to fix the chimney flashing "oh, major problem you need a who…

[deleted]

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

#288

Post by cma »

annoyingnoob wrote: post #79
cma wrote: post #49

Earlier quoted context omitted.

Are there buses?

In town, yes. Between towns, maybe/sort of/infrequently. I can drive to work in 15 minutes. The bus takes over an hour including 30 minutes of walking. There are no bike lanes between home and work, its possible to bike it but really not safe - I'd guess the bike would take about 40 minutes.

I'd imagine if a larger percentage of people took the bus, there could be much more frequent buses and dramatically less traffic on the roads making for faster busses.

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

#289

Post by xyzzyz »

Retric wrote: post #216
jacquesm wrote: post #205

Earlier quoted context omitted.

> daily solar output never drops to zero True, but it is also almost never 'rated power'. Typically a solar installation will deliver somewhere between 30 and 50% of rated power on average, depending on your latitude it might be even lower. The times when solar panels work at their best is during clear winter days and when they are capable of two axis adjustment. Because of the cost of such an installation the typica…

The economics of residential solar is heavily tied to local conditions. But, for grid solar there is little reasons to build it in the north rather than just move electricity from the south. We are already below 2c/kWh for solar power in some areas, the average consumer price is 13.27 cents per kilowatt hour in the US. That’s a lot of wiggle room. Let’s assume 50% over production that’s 4c/kWh, backed up by 60h worth…

> We are already below 2c/kWh for solar power in some areas

Yes, the power is very cheap exactly when nobody needs it.

> Let’s assume 50% over production that’s 4c/kWh, backed up by 60h worth of batteries and transmission and your still cheaper than Nuclear while covering base load and peaking power needs.

Can I see your calculations? Last time I did the math, building enough batteries to store 48 hours worth of US energy use was simply not viable.

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

#290

Post by moneytide1 »

NeedMoreTea wrote: post #76
bArray wrote: post #22

I think a major challenge that is yet to be addressed is the fact that solar panels lose their efficiency over time [1] [2]. Seems like you're looking at 80% of rated efficiency after 20 years - and I'm unsure this includes failures. In the UK a 50+ year old roof is very common - most people expect a house to outlast them without anything but minor repairs. If I were building a house I would want something where it's…

50 years is almost new. Most 100 year old terracotta tile are still on the original set, and slate often lasts 200. Where roofs are replaced, aside from storm damage, it's most common for that to be down to having got rot in the woodwork than fault with the tile. I suspect a fair few are down to iffy sales tactics from dodgy builders. (i.e. get someone out to fix the chimney flashing "oh, major problem you need a who…

A relatively routine roof replacement required because it is now expected to serve more than one purpose (simultaneous weather - proofed shelter and PV surface area) could be justified, especially if the entire neighborhood utilizes its existing local grid because the entire street of individually owned Powerwalls is one large shared, connected, metered (people with high energy needs could still run welders and power tools that pull from other Powerwalls), software driven reservoir:

Each existing home (even ones built in newly minted neighborhoods) would still be connected in parallel. It's the nearby 70-150kV subtransmission relay station historically feeding that parallel bank of homes that would become inactive - ironically bypassing the Nikola Tesla prompted long distance HV amperage flow from remote generation sources. AC implies spinning dynamos (loud flywheel momentum), and PV-to-battery is solid state, with high frequency silicon carbide switching (quiet). Classical home 13kV transformer bypassed or replaced with a small DC boost to launch amperage across the hundreds of feet of a neighborhood's acreage. Typical loads could be balanced even if a few people want to weld or smelt metals during a bright sunny day (especially summer solstice).

As a comment above pointed out, the solar capacity would decay over time, but since there is a local grid reservoir buffer - the reduced capacity PV over time can mean the high quality glass protection can be kept even when cells under them are down below 50%. Such a roof would be contributing less to the reservoir than neighbors feeding the same grid with newer solar roof replacement. The user can be paid for their generation if they use less than they produce, incentivizing low noise, subtle generation sources (charging your powerwall with an exercise bike like Jaimie Mantzel, adding your electric vehicle(s) charge reservoir to the neighborhood grid if next day commute will mean you're parked near other solar roofs that will top you off until ready to return home - transporting and trading energy).

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