Solar roof

[J.P.M.]

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

Thank you. Good info and lots to add to the conversation.

As for why folks are so gullible: People are lazy, only seeing what they want to see and only hearoing what they want to hear. P.T. Barnum was right, and seems to be getting more right all the time. Self induced ignorance from Iaziness is the real enemy. In one sense, con men like Musk are simply the opportunists taking advantage of that laziness.

[ButchDeal]

Thank you. Good info and lots to add to the conversation.

As for why folks are so gullible: People are lazy, only seeing what they want to see and only hearoing what they want to hear. P.T. Barnum was right, and seems to be getting more right all the time. Self induced ignorance from Iaziness is the real enemy. In one sense, con men like Musk are simply the opportunists taking advantage of that laziness.

also forgot to mention that the the conventional system was at 100% offset and size of 10.8kw, the Tesla solar roof seems to limit it to 60% offset based on the little info I gave (square foot of the home, monthly bill, and stories). I calculate it to roughly 8kw but here is my thought process on it:

Tesla claims 60% offset so one guess would be 60% of the size that we calculate is 100% offset, or 6.48kw
But that $43,100 value of energy indicates a larger system of about 7.6kw. This is all based on my dead south no shadow roof.
Since the Tesla system does not ask for azimuth or anything like that I would suspect that it is closer to 8kw

[J.P.M.]

also forgot to mention that the the conventional system was at 100% offset and size of 10.8kw, the Tesla solar roof seems to limit it to 60% offset based on the little info I gave (square foot of the home, monthly bill, and stories). I calculate it to roughly 8kw but here is my thought process on it:

Tesla claims 60% offset so one guess would be 60% of the size that we calculate is 100% offset, or 6.48kw
But that $43,100 value of energy indicates a larger system of about 7.6kw. This is all based on my dead south no shadow roof.
Since the Tesla system does not ask for azimuth or anything like that I would suspect that it is closer to 8kw

Understood. Given the paucity of actual design information from Musk at this time, if cost effectiveness and reliability are important, seems a perhaps prudent short term course of action for now might be to keep abreast of developments but take a wait & see approach, and keep the wallet closed.

[ButchDeal]

Understood. Given the paucity of actual design information from Musk at this time, if cost effectiveness and reliability are important, seems a perhaps prudent short term course of action for now might be to keep abreast of developments but take a wait & see approach, and keep the wallet closed.

well that is exactly the problem for us as well as any other sellers/installers out there. Homeowners are bedazzled by the Musk flashing lights and are wanting to get the solar roof or wait for it. I think as we find out more the story is going to get worse not better for solaroof, just like it did for the Powerwall 1 and most other vapor ware items like the zune v ipod.

[J.P.M.]

well that is exactly the problem for us as well as any other sellers/installers out there. Homeowners are bedazzled by the Musk flashing lights and are wanting to get the solar roof or wait for it. I think as we find out more the story is going to get worse not better for solaroof, just like it did for the Powerwall 1 and most other vapor ware items like the zune v ipod.

I believe we mostly agree on that one. Con men and their shills and others who only see what they want to see will be with us always. Musk and the snowflake, self centered and myopic treehuggers who enable his behavior are not much more than the latest iteration of such ethical bottom feeders applied to R.E.

Glad I'm retired. Hard enough sometimes trying to stay ethical and honest in business while dragging the anchor of the consequences of the actions of those like Musk behind you and at the same time cleaning up his spoor by (re)educating the public. It's just more business as usual I guess.

[SunEagle]

I did my roof with GAF lifetime warranty energy star shingles for $4k (installed)

+1. I worked at GAF corporate engineering for 6 years. They make a pretty good shingle.

[adoublee]

well that is exactly the problem for us as well as any other sellers/installers out there.

An interesting possibility that this could result in a net reduction of solar actually installed due to people who wait for it to be available or wait for a lower cost. I still haven't seen how the cells connect or how rapid shutdown is addressed (BIPV path of 2017 NEC?).

[ButchDeal]

An interesting possibility that this could result in a net reduction of solar actually installed due to people who wait for it to be available or wait for a lower cost. I still haven't seen how the cells connect or how rapid shutdown is addressed (BIPV path of 2017 NEC?).

they seem to be using option #3 for NEC 2017:

• 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.

[jflorey2]

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:

I have no doubt that they can make it work; they've made far harder things work, and solar is a pretty established technology. The question is - would you be better off with a much cheaper (and just as efficient) panel based system? From my very early estimates their system costs about 3x what a standard system does for the same power.

[adoublee]

[*]Option 3: Install nonmetallic PV array with no exposed wiring and array more than 8 feet from any grounded metal parts.[/LIST]

I guess gutter aren't grounded. Probably a no go for any house with lightning protection.

[tyab]

Butch - I was looking at the 2017 690.12 Rapid Shutdown stuff also and the only way I can see them making that work is to make a panel group that has some sort of microinverter or DC optimizer right there either directly part of that assembly or with a VERY SHORT cord (< 1') connecting it. Given that they want to have a flush appearance, lets say that module assembly attaches directly on the roof inside under the assembly. Then you run EMT/RMC/FMC to the other assembly modules and then have your final run to either inverters or interconnects if its an AC system. We will have to see what way they go - AC or DC when they ship real product. In any case a lot of penetrations in the roof so installers are going to have do a real good job making sure they are watertight. And given I believe those will have to be right under the roof - plan on them running in 140+F temps air environment.with no significant airflow around them so they will want to do a good job on the module engineering and not have the issues Enphase had at first. There is no question these tiles will be running hot so it will be interesting to see how that affects the overall output and $/watt.

[fresnoboy]

We're getting started on a build of a large home, and this would improve the look over a bunch of panels on the roof, about as optimal as possible for a tesla solar roof . But I don't understand the wiring system of what inverters they are planning to use, and how they deal with shading etc... It's hard to do a apples to apples comparison of the technology to more conventional approaches with the info that is available now.

I suspect we'll have to wait for them to actually build a few before we find out all the details.

Has anyone received a callback from them?

thx
mike

[SunEagle]

We're getting started on a build of a large home, and this would improve the look over a bunch of panels on the roof, about as optimal as possible for a tesla solar roof . But I don't understand the wiring system of what inverters they are planning to use, and how they deal with shading etc... It's hard to do a apples to apples comparison of the technology to more conventional approaches with the info that is available now.

I suspect we'll have to wait for them to actually build a few before we find out all the details.

Has anyone received a callback from them?

thx
mike

I would not hold your breath waiting on a call back.

As far as I know they haven't begun producing these shingles in any great amount to sell to the public yet. Give them at least until early next year before they start to go up on test roofs.

[J.P.M.]

I would not hold your breath waiting on a call back.

As far as I know they haven't begun producing these shingles in any great amount to sell to the public yet. Give them at least until early next year before they start to go up on test roofs.

And then give about 1,000 roof a 3 yr. test run to get things right, if ever.

As for callbacks, since this looks like SolarCity in a Tesla suit, you'll get callbacks until you're on the hook. After that, if my experiences with them (SolarCity) are any indication, the lack of professionalism on communication (and many other areas) means you won't get much in the way of information. I wouldn't expect much more out of the experience regardless of what they call themselves.

[peakbagger]

Given the upfront costs for panels I don't see a lot of folks writing checks for an install, therefore it becomes an opportunity to write solar leases which is where the real money is at. Solar roofs are being marketed as groundbreaking technology with no competitors, so Tesla will get the homeowner to ignore conventional panels. It also can indirectly be used to sell plain old solar panels. In theory putting a deposit process in place creates a fairly valuable client list. Tesla can then send a so called "engineer" or "technician" to the site to visit the owner. I expect the "engineer' is far more a salesman than an "engineer". Realistically it doesn't take lot of training to follow a canned site assessment checklist that can be mostly automated. The salesman then has a highly motivated customer and its up to the salesmen to bait and switch the homeowner into switching to plain old solar panels conveniently sold by Tesla now instead of the solar roof later. I expect that a big chunk of PV sales are now impulse purchases and expect that an average consumer wants near instant gratification. The more I see the more this lines up with the new and used car business.