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Solar roof

Solar roof

Has anyone on this board bought a solar roof? With or without a battery system?

I would love to do this to take me off of the electric grid completely. I am intrigued by the possibilities. My house has a very large roof surface area that would be perfect for a solar roof, I think.

Can anyone give me an estimate for the cost of installing one? If anyone has, can you let me know if you are happy with your decision? And does anyone have the batteries that would make your home self-sufficient?

Thanks

Earl and Nagin ... | 13. Juni 2019

@BBF,
The rule of thumb is that you need enough solar to handle at least twice your average daily usage and storage to handle 3 to 4 days worth of electricity in order to enjoy the kind of reliably available electricity to which we've become accustomed from our very good electrical grid in the USA.
You'll find this can cost more than twice as much as a simple grid-tied system would. Therefore, few actually do so.

blue adept | 14. Juni 2019

There is an initial up-front expense, but that can be financed or amortized, thing is that's all you'll ever have to pay for utilities ever again and, if you chose to, you can marginally expand your system beyond your needs and sell the excess charge/electricity to your local utility provider and use the proceeds to both help payoff your cost of installation and even establish a stream of zero labor, zero expense income that you can do whatever with.

There's a degree of typically unobtainable freedom in that that is priceless.

RuthJoan481 | 14. Juni 2019

The value of energy your Solar Roof is expected to produce over 30 years is based on the average price of electricity in your area, adjusted for inflation by 2% annually. Your ability to realize the full value depends on your home’s electricity usage, amount of energy storage available, and utility regulations on solar in your area. Electricity price estimates are sourced from the Energy Information Administration and solar production estimates are based on irradiance data from NASA. https://www.tellthebell.xyz/

Tesla2018 | 15. Juni 2019

There was an article that a solar roof costs about 65K and another 10 or 1tK for storage. Dont know if it was FUD or true.

I only use $1000 worth of electricity a year without the Tesla. I was given an estimate of between 20-60 K for a regular tile roof replacement. The higher amount was after their was a hurricane and people were getting ripped off. Would like to get one in 5 yrs when I need a new roof, but I dont think it would be cost effective and if I plan on moving in 10 yrs I doubt anyone would want to pay extra for a house just because it had solar panels. More people would be willing to pay an extra 50k for a pool instead.

BuffaloBillsFan | 15. Juni 2019

Thanks for all the replies. I want to get off the grid completely, and 60-70K does not seem outlandish to me. That said, I don’t plan to move anytime soon, and an electricity-for-free house may be more desirable when I do end up selling. I think I will look into it a little more . . .

Does anyone actually have a solar roof, and if so, what is your experience?

Thanks

greg | 15. Juni 2019

A recent article was published recently gives a good :1 year on perspective from an actual Tesla roof owner.

Google search for "inverse tesla solar roof 9 things"

jimglas | 16. Juni 2019

FWIW, I just spent 62k to have my hail destroyed "hail resistant" tile roof removed and a rubberized metal roof put on.
So $60k doesn't sound unreasonable at all.
(solar panels pending)

Tesla-David | 16. Juni 2019

Here is link to article @greg referenced. Interesting and generally positive summary of one year's experience with solar tile roof + PW2. With her setup she accrued an electric bill of only $119.61 for the entire year, which is not bad indicating the solar + PW2 provided most of her electricity, with minimum grid draws.

https://www.inverse.com/article/56754-tesla-solar-roof-9-things-you-don-...

BuffaloBillsFan | 16. Juni 2019

Thanks, all!

greg | 16. Juni 2019

@Tesla-David

Yes but she did not manage to go-off grid entirely, which is the @OP's desire.
Nor did the solar exports cover the connection cost, so there is a "minimal" Grid connection fee.

You could overcome both those issues.

But as with everything, there are likely more than a few trade offs involved.

Tesla-David | 17. Juni 2019

I know @greg. I am in a similar situation with 13.2 solar system + 2 PW2's. We are still connected to grid and our electric bill last year for the connection fee + some grid draws during winter when our solar was insufficient to cover our needs was $180 in Edmonds, WA. We are operating in self-powered mode with our PW2's which are an incredible complement to our solar, but because of where we live, we have 3+ months where we could not operate off grid due to insufficient solar + batteries to carry us through. If I lived in Hawaii, Texas, Arizona, Florida, etc. no problem.

Tesla-David | 17. Juni 2019

Oops 13.2 kWh solar PV system.

andy.connor.e | 17. Juni 2019

Solar roof prices are dropping. I expect (and was told to expect) next year for solar roof availability. Will revisit this next year.

jimglas | 17. Juni 2019

add another PW..... off grid
if that is your desire
$100/yr seems like a small compromise with 2 PWs

BuffaloBillsFan | 17. Juni 2019

@andy.connor.e.

I think I will do the same and revisit next year. This is a very high priority for me, but I have other projects that will perhaps make my house more eco-friendly in the short term this year.

Hopefully, the price will drop over the next year and I can tell the “grid” to piss off next year. The cost right now just seems excessive. . . .

Again, thanks for all who posted for their input!

Matt

Tesla-David | 17. Juni 2019

@BuffaloBillsFan,, where do you live? As I mentioned above, I live in Edmonds, WA, and have some solar challenges between November and mid February due to insufficient solar to satisfy our home and EV charging requirements even with our 2-PW2 batteries. Living off grid here would be very difficult. Obviously, reducing your energy footprint will help to satisfy your goal, which helped us tremendously. Good luck with your efforts and keep us informed about your progress and ultimate configuration. If I were doing solar today I would definitely consider doing a solar tile roof, and I believe EM is stating the cost should be coming down even more with the updated tile configurations.

blue adept | 18. Juni 2019

@Tesla-David

Available storage doesn't seem to be your issue as much as extended periods of inclement weather inhibiting your system's ability to recharge.

Given the particular weather conditions for your region, might I suggest the addition of a wind turbine? In particular, a vertical axis turbine? They've proven to be the most efficient from what's available out there and could prove to be a worthwhile supplement to your system, one that might even allow you to go fully off-grid.

andy.connor.e | 18. Juni 2019

I need a roof replacement in the next 2 years. So the way i see it, do it while theres still a federal tax rebate that can be rolled over to multiple tax years.

Tesla-David | 18. Juni 2019

Thanks @blue adept, I have long thought about adding wind turbines, but hesitated, but will seriously look at adding enough wind turbines to supplement our shortfall from solar from November to February. I have plenty of solar the remainder of the year to power our home, charge up our PW2's and two Tesla's. Looking at options (https://semtive.com/residential/) Semtive looks interesting. I am very much interested in finding alternatives that make us more self sufficient.

Earl and Nagin ... | 19. Juni 2019

@blue-adept,
Your statement that ". . . vertical axis turbine? They've proven to be the most efficient from what's available . . ." Disagrees with pretty much everything I've heard (and I've been around a lot of very smart people focused on turbine efficiency with a very good track record. Can you point to any supporting info for your statement?
My understanding is that their only benefit is their 'cool factor' because they don't look like 'just another propeller'.

greg | 19. Juni 2019

@Tesla-David

One of those bigger $6100 Semtive "S" models model do the trick for you - provided you get enough steady wind to drive it during Winter months.

With 24 MPH windspeeds, you could generate over 50 KWh in 24 hours.

The smaller one is only 1/4 the output, for half the price. So the bigger one is the best bang for your buck of the two.

But its only for Pilot projects right now. But it does output 110/240 volts so is intended as a grid tied option.

As for whether its the better compared to a normal horizontal wind turbine. Its likely very much your milage may vary based on many factors including your site specifics.

How deep the snow you get [too much will bury your vertical axis turbine maybe], or how high the turbines need to of the ground/roof to be clear of turbulence from trees other buildings etc. And.or how much directional change your location has in the wind - if the wind swings a lot a vertical axis would cope better. But if it always blows from the same direction, not much in it I'd expect.

blue adept | 19. Juni 2019

@Tesla-David & @Earl and Nagin ...

Granted, having no familiarity whatsoever with your (or anyone's) particular environmental situation (urban/suburban/rural) does make it hard to provide specific recommendations that are tailored to your regional or residential limitations/requirements so I just presumed that your (@Tesla-David) home was in an urban/city environment and suggested the vertical axis turbine-style because it has proven to be a more efficient energy producer in low wind applications (@Earl and Nagin ...).

Regardless you (or anyone) should definitely research the various alternatives available, including turbine styles, to find the one(s) that best suit your individual needs and not rely on anyone's advice or fall prey to some bourgie "cool factor".

Some research:

https://windexchange.energy.gov/small-wind-guidebook

Conversely, some efficient blade-style turbines:
https://eco-globe.com/best-residential-wind-turbines/

Overview of turbines:
https://www.semprius.com/wind-turbine-generator/

Another overview with some good insights (such as urban v suburban applicability):
https://wxobservation.com/best-home-wind-turbine/

Hopefully you're able to realize that I considered several factors before offering the suggestion I have, @Earl and Nagin ..., just keep in mind that it was only a suggestion, one based on the notion that @Tesla-David's living environment met certain constraints.

I do wonder, though, if it would amuse you to learn that one of the oldest (1,000 years old) forms of wind driven turbines is a vertical axis style:

https://video.nationalgeographic.com/video/news/00000159-74ce-da57-a97f-...

Again, everyone should exercise the due diligence of doing their research by reading and learning what options are best suited to their particular circumstances to ensure that they make the right choice(s).

Tesla-David | 20. Juni 2019

@greg, yes the bigger $6100 Semtive "S" models model looks like it might do the trick for us assuming that I could get one installed as they are doing only pilot projects right now as you mentioned. I have contacted them for more information, but have not heard back. I am grid tied living in the City of Edmonds, and am not really looking to be off grid with our current home, just looking to be as energy independent as possible. We have been on a sustainability quest for close to 7 years now, and our home was certified as being a Net Zero Energy Building (NZEB) in 2016 by the International Living Future Institute (https://living-future.org/lbc/case-studies/sustainable-dreams/). Our energy needs during the winter months are generally less than 30 kWh/day during the low solar period, when solar production dips to 8.6 - 18 kWh/da, which is insufficient to operate our all-electric home and charge both Tesla's (MS and M3). So the supplemental energy I need is around 20-30 kWh/day to keep us operational.

Thanks for the links @Blue adept for the links. I will look them over and endeavor to educate myself before doing anything about supplementing our solar. At this point I am not choosing any particular options, just exploring alternatives that would get me to more energy independence and less reliant on grid based energy. We are pretty independent for ~9 months of the year.

d4deeptibisht | 20. Juni 2019

Solor roof would be a great idea. However in order to conserve more, a battery driven system will be more effective as well as efficient.

andy.connor.e | 20. Juni 2019

You'll probably pay the same amount for solar panels as you will for powerwall.

Tesla-David | 20. Juni 2019

I have both solar + PW2 battery storage and believe they are essential and work exceptionally well together.

welcome | 20. Juni 2019

Hi BBF,

You could try to create a new module in the PV sol database and enter all the details that you know of so far. The dimensions were published, and if you found out the specific power in W/m² you can calculate the nominal power of a tile by multiplying it by the area.

So, one tile is 184 mm wide and 365 mm long, which gives 0.067 m². I don't know the specific power you have found out, but if I should estimate the efficiency of the tiles, I'd say they have around 10 %.

This would give a nominal power of 1000 W/m² * 0.067 m² * 0.1 = 6.7 W.

Then, when you enter the voltage and current details on the next page, I would recommend to set the number of cells to 2, and adjust the voltage values accordingly. After that, adjust the currents:

In the section electrical data set the number of cells to 2.
In the STC section, enter the nominal power of 6.7 W in the field top right
Change the voltage values to a 2/60th of their original values:
MPP: 28.3 V / 60 * 2 = 0.943 V
open circuit: 36.1 V / 60 * 2 = 1.203 V
The nominal power of 6.7 W is the product of MPP voltage and current, so you have to adjust the MPP current to 6.7 W / 0.943 V = 7.12 A.
Since the ratio of MPP current to short circuit current should be left as is, you also have to change the shor circuit current to 7.12 A * ratio_I = 7.12 A * 7.7 A / 7.07 A = 7.75 A
The thermal voltage coefficient should be adjusted as well, set it to -0.35 %/K.
With those values you should be good to go. Of course that is mere guessing, but if you really want to simulate these systems already, this is what you could do.

Kind regards,
Thomas

LinkedIn: www.linkedin.com/in/generator0n
Twitter: twitter.com/Generators_On
Website: generatoron.org

blue adept | 21. Juni 2019

@Tesla-David

Granted a suburban even rural setting is the most ideal for the goal of achieving off-grid sustainability than an urban one due to the typically ready access to natural resources as opposed to the housing/building/utility restrictions that are inherent in 'city' living which, all things considered, is why solar is the more so favorable option with wind running a close second, again, for 'city' living because they more easily blend in the urban aesthetic.

Now if you were situated at a suburban or especially rural or remote location, then your options are limited only by what resources are at hand.

Good luck with your endeavor to become energy self-sufficient!

BuffaloBillsFan | 22. Juni 2019

@welcome,

OMG! Can I have someone for Tesla do that for me? I am smart but not that smart, at least when it comes to electricity and solar energy. Thanks for the advice, but most of what you advised flew a few miles above my head.

If I wanted a solar roof and PW storage to take myself off the grid completely, would they come out and assess? Or is there anyone else who could assess my house for suitability?

Matt

Tesla2018 | 23. Juni 2019

I keep getting ads for solar panels now that Florida Power and Light is being forced to buy back excess power. How much does a regular non Tesla solar panel on the roof system cost and can they be installed on a barrell tile roof? Im just afraid that in a hurricane, they would go flying off taking the tiles and ripping off part of the roof. Would rather have solar roof tiles instead but since I only use $1000 worth of electricity a year it wouldnt be worth it. I believe a powerwall costs $5k but are they only needed if you need power in an event of a storm? The energy from the panels would offset part of my regular bill so would need to get a powerwall if I have a genetator in case of a power failure?

andy.connor.e | 24. Juni 2019

I think the true value of the solar roof is that it doesnt need to be replaced regularly.

TeslaTap.com | 24. Juni 2019

@Tesla2018 - Powerwall is optional and serves as a whole house UPS. If you want to use all your electrical appliances and/or plan for a long outage, you may need multiple Powerwalls. If you can live without power, then no Powerwalls are needed. Note that most solar systems do not provide any house power in an outage, as they disengage to protect utility workers.

I think a regular solar panel can be installed on any type of roof. They have to attach them directly to beams under the roof tiles. May need additional bracing for hurricane areas, but I'm sure it can be done. You'll need to talk to a solar installer to get more details - just about every installation is custom.

blue adept | 24. Juni 2019

@Tesla2018

How much a PV panel system (since you've expressed you're not interested in Tesla's because you couldn't justify the cost) would cost for your particular roof would be dependent on the solar provider you chose to go with, so you should do some research on the various solar companies, what services they provide and the costs for said services as well as invest the time in placing some calls to the companies' customers to see what sort of experience they've had with their product, you know, exercise a little due diligence to make sure you don;t get scammed.

Most, if not all, solar installation companies have an installation system specifically designed to address your particular structural and regional needs as well as provide warranteed work to cover the costs of any damage from "weather events", just be sure to check their credentials to ensure that they do.

Typically Powerwalls store electricity for time of use load shifting (so you can charge your Tesla(s) without drawing/stealing any power from your home's typical electrical utilities/powered fixtures and appliances so there are no interruptions), backup power (should the power go out during an inclement weather event), and off-the-grid use (if you want to be completely free of public utility charges).

To that end a Powerwall would negate the need for a "generator" if the power went out during a storm inasmuch as you'd be able to make use of the power stored in the Powerwall in the case of a power outage.

blue adept | 24. Juni 2019

@andy.connor.e

Well, there's also that, though that's typically viewed as a secondary (though no less invaluable) benefit to the primary benefit of being able to freely generate your own power from the natural resource of the Sun devoid of any utility company services.

blue adept | 24. Juni 2019

@TeslaTap.com

>>> "- just about every installation is custom."

Yep!