Solar roof

[silverhorsefarm]

I know there's a LOT of skepticism on this forum about Tesla's promised solar roof, but I remain optimistic that they can make it work:

https://techcrunch.com/2017/05/10/teslas-solar-roof-tiles-go-up-for-pre-order-today/

[SunEagle]

The proof of it working will be a number of successful installations that last as long as advertised. Maybe Tesla has found the right combination of materials to make their product work. Although it has been tried by other well know companies (like DOW) with poor results. I guess we will have to wait and see.

[J.P.M.]

Believe what you want, and spend your money as you wish, but wait until such a product is proven safe, practical and cost effective by independent confirmation and use by the great unwashed masses before you sink any money into such a product, or spread B.S, advertising around like this. Others may fall for it.

[silverhorsefarm]

I understand the reservations of the critics, but it looks like a pretty compelling product:

https://electrek.co/2017/05/10/tesla-solar-roof-tiles-price-warranty/

[J.P.M.]

I understand the reservations of the critics, but it looks like a pretty compelling product:

https://electrek.co/2017/05/10/tesla-solar-roof-tiles-price-warranty/

I've got a bridge for sale. Wait until enough are up/running for a while to get some idea of robustness, and then do a cost analysis on one for your home and your loads. If all that works out, and it's cost effective, it'll be compelling. Until then, it's no more Musk B.S. of the usual variety.

[silverhorsefarm]

Yeah, JPM, I Get where the skepticism comes from. But IMHO, the bile, negativism, and outright hatred of all things Musk on this forum is disproportionate. I think he is courageous. Yes, he is the beneficiary of a LOT of public funding largess. Yes, he over promises and under delivers. BUT, he has moved the needle on sustainability and space travel like no one else. Let's give him the benefit of the doubt.

I've got a bridge for sale. Wait until enough are up/running for a while to get some idea of robustness, and then do a cost analysis on one for your home and your loads. If all that works out, and it's cost effective, it'll be compelling. Until then, it's no more Musk B.S. of the usual variety.

[SunEagle]

Yeah, JPM, I Get where the skepticism comes from. But IMHO, the bile, negativism, and outright hatred of all things Musk on this forum is disproportionate. I think he is courageous. Yes, he is the beneficiary of a LOT of public funding largess. Yes, he over promises and under delivers. BUT, he has moved the needle on sustainability and space travel like no one else. Let's give him the benefit of the doubt.

Sure Musk has done things no one else has and yes he has move the needle on space travel. But does the end justify the means?

There are other people in the world that I feel are in better position to be admired then someone that uses slick commercials and promises to get public funding to build his empire.

Solar shingles is not new. Tesla's jump into the market may be nothing more that a way to get attention moved away from not providing other products as promised.

There is really no magic. Most tricks are completed by slight of hand or getting the viewer to watch something while the "entertainer" is doing something else.

History shows that there are many people that have shown great success and achieving success by standing on the backs of others.

All I can say is Buyer Beware.

[J.P.M.]

Yeah, JPM, I Get where the skepticism comes from. But IMHO, the bile, negativism, and outright hatred of all things Musk on this forum is disproportionate. I think he is courageous. Yes, he is the beneficiary of a LOT of public funding largess. Yes, he over promises and under delivers. BUT, he has moved the needle on sustainability and space travel like no one else. Let's give him the benefit of the doubt.

Musk is a con man. His contributions to society, whatever they may be, and regardless of what you, I, or anyone thinks of their worth, are paid for by a combination of gov. largess and money he bilks suckers out of. Whatever those product benefits may be, they are certainly, IMO anyway, less than the gain realized by society as a whole from their existence, and particularly not worth it to all the people stuck with, for example, SolarCity leases, or future products brought to market too soon (solar shingles being an example) and sold to solar ignorant fools.

P.T. Barnum was right.

[ButchDeal]

looking at the 2017 rapid shutdown code it looks like there are three options:

• Option 1: List and label or field-label PV array as a rapid-shutdown PV array.
• Option 2: Limit control conductors within the array boundary to 80 V or less within 30 seconds of rapid-shutdown initiation.
• Option 3: Install nonmetallic PV array with no exposed wiring and array more than 8 feet from any grounded metal parts.

It seems to me that option 3 is no where near as safe as the other two options
It could be hard to impossible to actually meet the option 3 requirements if the home has lightning rods, TV antenna, or metal siding

[emartin00]

Yeah, JPM, I Get where the skepticism comes from. But IMHO, the bile, negativism, and outright hatred of all things Musk on this forum is disproportionate. I think he is courageous. Yes, he is the beneficiary of a LOT of public funding largess. Yes, he over promises and under delivers. BUT, he has moved the needle on sustainability and space travel like no one else. Let's give him the benefit of the doubt.

You have 2 sentences in the same paragraph that completely contradict themselves. Why would I give him the benefit of the doubt, if he has a record of over promising and under delivering?

[peakbagger]

My thoughts/impressions

They are a nice looking roofing system. If they are made of durable materials as claimed and a "50 year roof" is possible who cares if they generate power. In theory since they are made out of "glass" they also should be fireproof. That's another nice option totally unrelated to solar. I expect with a modified bitumen underlayment (grace storm shield) its potentially a long lasting roof.

I haven't seen any details on panel interconnections, this was a bane of past solar shingle products. I hope they have some sort of common connector for each course that runs out to a hidden gutter compared to having numerous roof penetrations from individual cables. Even if they come up with some sort of resilient sealing system for these wires, that's probably the Achilles heel of a long term roof system as there are few long term resilient sealing materials that will survive a roof environment. The heat just bakes them.

Given that they are going to be custom engineering each installation I expect that they are going with string type wiring to reduce cost. I expect they will design the layout to avoid shading as adding optimizers or microinverters add a lot of complexity and cost.

A big question to me is on less optimized exposures like North facing roofs is the plan to just install 100% dummy panels?. That obviously dilutes the solar subsidy for much of the building as its not generating power on possibly 50% of the building. The alternative is to go with a less cost roofing system on the shaded exposures which negates the potential longevity and fire retardant issues if the entire roof doesn't use the system.

I expect the pricing has a hidden subsidy like Tesla cars by getting another revenue stream from another source, given that the system appears to be integrated to a powerwall battery, I expect that there may be some strings attached to the user agreement that allow Tesla to "borrow" battery capacity for short periods. The logical approach is to sell the capacity of the battery into a five minute capacity market or the frequency regulating market. Effectively this gives Tesla a very nice revenue source not available to the homeowner that can buy down the initial panel cost by "borrowing" the batteries output occasionally for short periods.

[silverhorsefarm]

My assumption would be that the only inverter is the one integrated with the powerwall.

[ButchDeal]

My assumption would be that the only inverter is the one integrated with the powerwall.

you can get it without the powerwall ...

[solarix]

What I want to know is: Why are so many people so enchanted by the whole Tesla/Solar City brand?

The long term results are not in yet of course, but from a practical standpoint, the brand is more hype than value. I think it is because people just love to be optimistic and forward thinking, longing for a better world - ready to believe the snake oil salesman that says his product is the next great thing. Well - we need dreamers to try new things and develop progress and the Tesla cars have changed the automotive industry to get on with electric drive (but probably the Prius was even more instrumental) and SpaceX has changed the rocket industry, and SolarCity has rolled out fair-quality/affordable rooftop solar to the masses (still unprofitable company with rip-of leases). All in all though - I haven't bought into any of these products yet and won't be doing Solar Freakin' Roofs either. Ya - "solar freakin roadways": that's a good one, I rest my case.....

[ButchDeal]

What I want to know is: Why are so many people so enchanted by the whole Tesla/Solar City brand?

Don't really know. I feel that it is people who don't know much about technology or construction, or pricing and can't be bothered to look more than the headline. It is the day we are in, so few people know much about construction or practical things in general any more.

I did some quick math based on my re-roofing and general pricing for conventional solar of $3/15/w (our base price without any promotion codes) in my state of WV

I did my roof with GAF lifetime warranty energy star shingles for $4k (installed)
This is not my solar system but a battery less larger system with our current costs, and pulled the solar roof right off their estimator.

standard:
cash cost for roof and solar : $38k
federal incentive for solar: $10.2k
total Cost $27.8k
Total value of solar $61.4k

30 year net savings $33.6k


Tesla:
Cash for roof and solar: $55.6k
Federal incentive: $14.2k
total Cost $41.4k
Total value of solar $43.1k

30 year net savings $1.7k

and this does not take into account that the solar roof likely will weigh more and require more structural work to maintain the required roof snow load, the conventional racking system adds rigidity. It is also safer:

They managed to get a special line in the code for 2017 code (not yet implemented any place).
For 2017 arrays will have to have integrated logic like the SolarEdge solution or the Tigo solution.

• Option 1: List and label or field-label PV array as a rapid-shutdown PV array.
• Option 2: Limit control conductors within the array boundary to 80 V or less within 30 seconds of rapid-shutdown initiation.
• Option 3: Install nonmetallic PV array with no exposed wiring and array more than 8 feet from any grounded metal parts.

It seems to me that option 3 is no where near as safe as the other two options
It could be hard to impossible to actually meet the option 3 requirements if the home has lightning rods, TV antenna, or metal siding