Go Back   Winnipesaukee Forum > Winnipesaukee Forums > Home, Cottage or Land Maintenance
Home Forums Gallery Blogs YouTube Channel Classifieds Links Calendar Register FAQDonate Members List Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Display Modes
Old 02-22-2021, 01:38 PM   #1
LakeTimes
Senior Member
 
Join Date: Jan 2017
Location: NA
Posts: 97
Thanks: 29
Thanked 12 Times in 9 Posts
Default Tesla Solar Roof Install

Curious to know if anyone on here has a Tesla Solar Roof? If so, any feedback? Which version did you install (current version is V3)?

For those that aren't aware and want to read more about them in general as to what I'm referencing: https://www.tesla.com/solarroof

Much like panels - snow doesn't seem to be an issue. Haven't heard/read much in regards to any differences in heat loss with them vs a standard roof.

Video I've found of someone building their new home in WI and how the roof performs with snow: https://www.youtube.com/watch?v=f_GHVSL35-k

I've been watching and tracking Tesla Roof Shingles since the announcement years ago when they were very expensive - but with new version, further R&D and innovation, volume, etc. they are now much cheaper and similar price to putting on Solar Panels.

I've got a multifamily house (4 units) in Portsmouth and need to replace the roof this year. Was considering finally biting the bullet since the roof needs to be replaced either way. I don't like the look of solar panels on roofs, I know the neighbors don't either, but this would alleviate that concern. My thought would be to throw some TESLA Powerwalls in the basement (https://www.tesla.com/powerwall) where no one goes anyways and move to 'paying for the electric' for all the tenants. The house in total in 3200 square feet with QTY 2 - 1 BR units and QTY2 - 2 BR units. Thus I could replace my roof, take on solar and get a better ROI, not have to worry about the power going out and heating being lost etc etc. etc. If prices are similar, not so sure why I shouldn't go this path.

Either way - curious if anyone has installed a Tesla Roof here in the Northeast, their feedback or other general feedback from others.
LakeTimes is offline   Reply With Quote
The Following User Says Thank You to LakeTimes For This Useful Post:
AC2717 (02-22-2021)
Old 02-22-2021, 02:59 PM   #2
FlyingScot
Senior Member
 
Join Date: Jun 2016
Location: Tuftonboro and Sudbury, MA
Posts: 1,254
Thanks: 707
Thanked 549 Times in 328 Posts
Default

You should check to see if the Tesla service area includes you--I don't think they are everywhere yet.

On the look of normal solar panels--you should look at all black panels. I have them on my roof, and they are very sharp--much better looking than the typical panels with silver grids, especially if you add all black critter guards around the edge.

If your electric company does net metering, the Powerwall will not be a good return on investment, except as an alternative to a generator. Check with your solar salesperson.

In general, these are great investments. Good luck!
FlyingScot is offline   Reply With Quote
The Following 2 Users Say Thank You to FlyingScot For This Useful Post:
LakeTimes (02-22-2021), VitaBene (02-23-2021)
Old 02-22-2021, 03:18 PM   #3
LakeTimes
Senior Member
 
Join Date: Jan 2017
Location: NA
Posts: 97
Thanks: 29
Thanked 12 Times in 9 Posts
Default

Quote:
Originally Posted by FlyingScot View Post
You should check to see if the Tesla service area includes you--I don't think they are everywhere yet.

On the look of normal solar panels--you should look at all black panels. I have them on my roof, and they are very sharp--much better looking than the typical panels with silver grids, especially if you add all black critter guards around the edge.

If your electric company does net metering, the Powerwall will not be a good return on investment, except as an alternative to a generator. Check with your solar salesperson.

In general, these are great investments. Good luck!
Thanks FlyingScot. Great question as I wasn't sure either. I know the last time I checked (well over a year ago), they weren't, but as of today Portsmouth is per their website. Checked Lake Address as well and same which is positive news. Guessing they must have enabled a few roofing companies in various regions to do this and aren't using their own 'installers,' but I very well could be wrong as that is just an assumption.
LakeTimes is offline   Reply With Quote
Old 02-22-2021, 10:48 PM   #4
FlyingScot
Senior Member
 
Join Date: Jun 2016
Location: Tuftonboro and Sudbury, MA
Posts: 1,254
Thanks: 707
Thanked 549 Times in 328 Posts
Default

Quote:
Originally Posted by LakeTimes View Post
Thanks FlyingScot. Great question as I wasn't sure either. I know the last time I checked (well over a year ago), they weren't, but as of today Portsmouth is per their website. Checked Lake Address as well and same which is positive news. Guessing they must have enabled a few roofing companies in various regions to do this and aren't using their own 'installers,' but I very well could be wrong as that is just an assumption.
It will be super if you can do it--you'll be one of the very first in the area. Keep us posted!
FlyingScot is offline   Reply With Quote
Old 02-23-2021, 10:31 AM   #5
mswlogo
Senior Member
 
Join Date: Jun 2014
Posts: 284
Thanks: 110
Thanked 112 Times in 73 Posts
Default

In MA and I assume NH unless you have off peak rates the PowerWalls donít pay to install. With Net Metering I essentially have an 80% efficient battery now (called the grid). I push 100% of my overage (in summer) to the grid but I only get 80% back. When I need it (in winter). Itís also unlimited capacity and 0 phantom losses. And 0 degradation over time and lifetime guarantee. Oh and itís also free.

With a PowerWall you get 92% efficiency. limited capacity. Phantom losses. Degradation and 10 year warranty. And they are expensive.

They are good for the grid and there are incentive programs.

Curious what you think your ROI will be.

Personally I donít think Solar Panels look that bad if installed nicely.
I plan to install Solar in NH and own a Tesla. But it wonít be Tesla shingles nor PowerWalls. What if you need repairs on roof shingles. I might do a ground based system so I can easily remove snow and place they at the most efficient angle and direction.

Note that the most efficient time of year for my solar system is not summer. Itís later spring. Because the panels are cooler. And air can flow under them to keep them cool. How do shingles stay cooler? Maybe Tesla has an answer for this.

I love new tech but I donít have the guts to use the new solar shingles.

If you do go for it, good luck.
mswlogo is offline   Reply With Quote
The Following User Says Thank You to mswlogo For This Useful Post:
LakeTimes (02-23-2021)
Sponsored Links
Old 02-23-2021, 11:09 AM   #6
FlyingScot
Senior Member
 
Join Date: Jun 2016
Location: Tuftonboro and Sudbury, MA
Posts: 1,254
Thanks: 707
Thanked 549 Times in 328 Posts
Default

Quote:
Originally Posted by mswlogo View Post
In MA and I assume NH unless you have off peak rates the PowerWalls donít pay to install. With Net Metering I essentially have an 80% efficient battery now (called the grid). I push 100% of my overage (in summer) to the grid but I only get 80% back. When I need it (in winter). Itís also unlimited capacity and 0 phantom losses. And 0 degradation over time and lifetime guarantee. Oh and itís also free.

With a PowerWall you get 92% efficiency. limited capacity. Phantom losses. Degradation and 10 year warranty. And they are expensive.

They are good for the grid and there are incentive programs.

Curious what you think your ROI will be.

Personally I donít think Solar Panels look that bad if installed nicely.
I plan to install Solar in NH and own a Tesla. But it wonít be Tesla shingles nor PowerWalls. What if you need repairs on roof shingles. I might do a ground based system so I can easily remove snow and place they at the most efficient angle and direction.

Note that the most efficient time of year for my solar system is not summer. Itís later spring. Because the panels are cooler. And air can flow under them to keep them cool. How do shingles stay cooler? Maybe Tesla has an answer for this.

I love new tech but I donít have the guts to use the new solar shingles.

If you do go for it, good luck.
You don't want to mount panels on an old roof, but they are easily removed and reinstalled in the unlikely case you need to repair shingles, and as you'd expect, all decent installers insure you for any damage done during install.

I would not hesitate on the newness on the shingles--they a lot lot simpler than a car
FlyingScot is offline   Reply With Quote
The Following User Says Thank You to FlyingScot For This Useful Post:
LakeTimes (02-23-2021)
Old 02-23-2021, 12:56 PM   #7
LakeTimes
Senior Member
 
Join Date: Jan 2017
Location: NA
Posts: 97
Thanks: 29
Thanked 12 Times in 9 Posts
Default

Quote:
Originally Posted by FlyingScot View Post
You don't want to mount panels on an old roof, but they are easily removed and reinstalled in the unlikely case you need to repair shingles, and as you'd expect, all decent installers insure you for any damage done during install.

I would not hesitate on the newness on the shingles--they a lot lot simpler than a car
All great questions and points. As FlyingScot said - they actually clip together relatively easily (not that I would do it, but for others to repair) and are warrantied. They are supposed to be highly durable (ie - take a hammer to them and no damage to the Tesla Shingle per several video's i've seen). I switched the house over to propane from oil (and soon natural gas when that's available on the street which Portsmouth says is coming in the not too distant future). When i took 3rd floor unit down to studs and redid, I removed one of the chimneys sticking above the roof. I've got one more chiney left which I plan to have taken down to below roofline so I don't see any damage coming from anything else (unless something falls from the sky like parts of plane engines potentially) . All tree and tree branches that could hit the 'roof' i've cut back or had taken down to bring more natural light to the property.

Your point is very well taken regarding the Powerwall. As it's a rental property (4 units), no Teslas or other EV's will be tapping the system for the foreseeable future, I'm not sure I need one. Doesn't mean that can't change, but if it does, I could always add that at a later date. Guessing prices will continue to decline as volume increases. My only thought for getting one was consistency in power and second in case the power goes out (Which only happens a few times a year in Downtown Portsmouth), the house would still have power for X time - whatever X is... Right now, I get calls that Power is out and during the winter, I do bite my nails that it will stay out for a long period of time to the point where i would need to bring my generator over. Both points I need to do more research on and collect more professional opinions, which is one of the reason for the post, so thank you :-)

Regarding ROI - I dont' have that exact number for you. To dive deeper into the details, I need to replace the entire roof anyways, so there is a cost to that already. The million dolar question is what is the price premium for the Solar Shingles over standard shingles. I pay $130ish per month for one units electric (as it has community lights, outdoor lights, etc. tied to his meter and don't feel it's right that he inherit that bill), plus I feel I could add the rest of the units onto the solar shingles and essentially up each units rent $100 or so a month. So I look at it as i would get roughly $400+ in electric revenue per month, thus $4800 per year. We will see where final figures come in, but since replacing the entire roof already, the cost premium ROI I'm guessing is just a few years at most.

Link to one of the various financial calculations out there (Date: Jan 2021)
https://www.solarreviews.com/blog/te...match-the-hype

Regarding MSWLogo's question: "Note that the most efficient time of year for my solar system is not summer. Itís later spring. Because the panels are cooler. And air can flow under them to keep them cool. How do shingles stay cooler? Maybe Tesla has an answer for this." --- Great point and question and from what I can gather:

Tesla currently installs the roof with air underneath the tiles. They are more than strong enough to support 'a lot of weight' on them. Not sure what a lot of weight is, but could probably dig it up. The second video in this link shows the install of Tesla Solar Shingles and you can see the gap between the roof and Tesla Shingles: https://pv-magazine-usa.com/2020/10/...-sons-roofing/

Looks to be a solid inch or two. I've watched several installation videos to see how it comes together. Makes a lot of sense to be. I just know I wouldn't want to be on the shingle side on my roof due to the steep pitch
LakeTimes is offline   Reply With Quote
The Following User Says Thank You to LakeTimes For This Useful Post:
FlyingScot (02-23-2021)
Old 02-23-2021, 02:11 PM   #8
mswlogo
Senior Member
 
Join Date: Jun 2014
Posts: 284
Thanks: 110
Thanked 112 Times in 73 Posts
Default

Quote:
Originally Posted by FlyingScot View Post
You don't want to mount panels on an old roof, but they are easily removed and reinstalled in the unlikely case you need to repair shingles, and as you'd expect, all decent installers insure you for any damage done during install.

I would not hesitate on the newness on the shingles--they a lot lot simpler than a car
I agree you, you want a fresh roof. I had a bee roof installed fir mine.

I’ve see people spend $100K+ on these Tesla solar roofs. I’ve never heard of a traditional panel system be over $40K (for large systems).

That’s why they are on V3 in a few short years.

Don’t get me wrong I love the concept. But it’s risky.

The complex part is interconnections. You have connect electrically every shingle.
I think it’s designed to allow failures though.

These might be safer in more fair weather states.

NH winters can be brutal. Wide swings in temps, ice etc.

If someone wants to try it, go for it.
But I’d stick with proven and cheaper technology.

If you have $5,000,000 home, then maybe it’s worth it.

I actually like a nicely installed solar. Looks modern and green.

They did an awesome job on mine. Not a single wire shows.
It’s also been repaired 3 times in 4 years under warranty. Optimizers blew.

I researched these shingle roofs before and I think they need some access under the roof for inter connections. I forget details. There are videos on YouTube.

If I recall it made more sense on new construction.
mswlogo is offline   Reply With Quote
Old 02-23-2021, 05:51 PM   #9
FlyingScot
Senior Member
 
Join Date: Jun 2016
Location: Tuftonboro and Sudbury, MA
Posts: 1,254
Thanks: 707
Thanked 549 Times in 328 Posts
Default

msw--you might check the link from LakeTimes on cost--showing a Tesla roof at $2.01/watt (and that includes the roof itself!). If accurate, that would be shockingly low--I paid over $3/watt, just for standard (high end) solar.

Agreed that a standard solar roof is more proven--there are millions of them working trouble-free.

I look forward to LakeTimes's report on actual price quotes
FlyingScot is offline   Reply With Quote
Old 02-23-2021, 06:02 PM   #10
Biggd
Senior Member
 
Join Date: Nov 2016
Location: Waltham Ma./Meredith NH
Posts: 2,997
Thanks: 1,385
Thanked 860 Times in 537 Posts
Default

I personally don't think solar panels look attractive at all. When looking at homes I avoid any home with solar panels. I certainly wouldn't pay extra for them, JMO.

Sent from my SM-G950U using Winnipesaukee Forum mobile app
Biggd is offline   Reply With Quote
Old 02-23-2021, 07:44 PM   #11
thinkxingu
Senior Member
 
thinkxingu's Avatar
 
Join Date: Jul 2014
Posts: 4,091
Thanks: 1,042
Thanked 1,306 Times in 783 Posts
Default

LakeTimes, thanks for the question. I'm going to need a new roof in the next decade, and the idea of solar tiles is an incredibly interesting one. I would need to convert from electric baseboard to a lower-draw heat source, but if the costs of a solar roof were to be less expensive than both a roof AND solar, it could be a win-win.

Sent from my SM-G950U using Winnipesaukee Forum mobile app
thinkxingu is offline   Reply With Quote
The Following User Says Thank You to thinkxingu For This Useful Post:
LakeTimes (02-24-2021)
Old 02-23-2021, 09:26 PM   #12
mswlogo
Senior Member
 
Join Date: Jun 2014
Posts: 284
Thanks: 110
Thanked 112 Times in 73 Posts
Default

Quote:
Originally Posted by FlyingScot View Post
msw--you might check the link from LakeTimes on cost--showing a Tesla roof at $2.01/watt (and that includes the roof itself!). If accurate, that would be shockingly low--I paid over $3/watt, just for standard (high end) solar.

Agreed that a standard solar roof is more proven--there are millions of them working trouble-free.

I look forward to LakeTimes's report on actual price quotes
Wait until the real quote comes in.

@FlyingScot how big is your system? is it in NH? Do you get Net Metering? Which Electric Company?

I just put a mock system into Tesla's calculator. 10kW system NH (that's on the small side for NH, that would be huge in Florida)

It came out to $32,797 or $3.29 / watt (before credits).
It came out to $25,379 or $2.53 / watt (after credits).

Still, not terrible considering you get a roof with it. Maybe that article subtracted the cost of the the roof to reach $2.01 / watt

With 2 Power walls

$49,797.00 (before credits)
$37,959.00 (after credits)

Warranty is 25 years on shingles including labor. Good.
10 years on inverter etc. Not so great.

I got 20 years on everything on my system. I paid like $3.00 / watt before credits, 4 years ago.
I also got MA SREC, which essentially made it break even after 6.5 years. After that, it's profitable for 3.5 more years.
It would have been very hard to justify the Solar without that SREC program. With out that break even would have been like 18 years.

Another way to look at it, is to amortize it.
Take that $37,959.00 and amortize it over the life of the system, I like to use 20 years.
That comes to $158.00/mo compare that to your electric bill. But that assumes 10kW (which is typical).

Let's assume the 10kW system produced 10gWh per year (since mine in MA is close to 7.8kW produces 8gWh, my sun exposure is maybe a B+, neighbors tree blocks part of the day)
Let's amortize Solar Only (no power wall, with credits). That comes to $105.00/mo (for 20 years) for the $25,379 system above.
So 10gWh is 833kWh per month. That's $0.126 / kWh. What's NH rate, I think we pay $0.17 / kWh.
It would cost $141.61 for 833kWh with no Solar. So you save $36 / month with Solar.
How many years will it take to cover that $25,379.00 investment? 58 years to break even !!! See why I said without SREC it's hard to justify Solar. Also MA is $0.26 / kWh so bigger savings.

My MA system is 7.8kW and produces roughly 8gWh per year. Further north you go the larger the system you need.
And our house is ALL gas appliance and heat. So it's a small system. Our bill was like $125/mo.

Note also my system had to produce 20% over what I used to cover everything. Because most of what it produces goes into the grid.
And I only get 80% back (at no cost) i.e. Net Metering.

LakeTimes said it's a multiunit with 4 units. I bet it cost on the order of $150K to $200K (if he include the power walls he wanted, min of 4?).
Not sure how they would break it all up if it's all separately metered.
It might basically be 4 installations (most credits might only apply to 1 installation [per year?]). If installed as one system you might hit limit for residential.
There are caps on residential sizes and this might get labeled as commercial. So that might all get complicated what the true costs will be. Commercial might have even better incentives.

PowerWall's really only pay if the electric company does NOT offer Net Metering (storing your excess production on the grid for reasonable cost), basically makes the grid your battery (or power wall). Or PowerWall's are great if you have no Solar and have off peak rates. You charge the Power Wall during the cheapest rate and then use them at the peak rates. For Solar with Net Metering (at a good rate) they will never pay for themselves. Unless there are special incentives. There are in some incentives in MA (like SRECS).

Last edited by mswlogo; 02-23-2021 at 10:09 PM.
mswlogo is offline   Reply With Quote
Old 02-23-2021, 11:22 PM   #13
FlyingScot
Senior Member
 
Join Date: Jun 2016
Location: Tuftonboro and Sudbury, MA
Posts: 1,254
Thanks: 707
Thanked 549 Times in 328 Posts
Default

Quote:
Originally Posted by mswlogo View Post
Wait until the real quote comes in.

@FlyingScot how big is your system? is it in NH? Do you get Net Metering? Which Electric Company?
Agreed LT needs the real quotes.

I have an 18kW system, I paid $56,000, and I'm on Eversource in Mass. It's on the large and expensive side--it powers my car and a house full of minisplits, and I got all black panels for the look. Like yours, the system will pay for itself in a bit more than 6 years; the annualized rate of return (IRR) is about 18%. As you said, the Solar Investment Tax Credit and the SRECs make it an excellent investment.
FlyingScot is offline   Reply With Quote
Old 02-24-2021, 11:26 AM   #14
NH.Solar
Senior Member
 
NH.Solar's Avatar
 
Join Date: Jan 2017
Location: Jackson Pond, New Hampton
Posts: 135
Thanks: 24
Thanked 67 Times in 36 Posts
Default

I have of course been following this thread with great interest, and there has been some good info presented, and some that is not accurate in NH.
The Tesla roof panels, like the solar window films and flow batteries sound intriguing and very promising but in my opinion not yet ready for prime time, and especially in an environment as harsh as northern New England's. Plus as pointed out the installation is incredibly expensive at this point.
The focus of NH Solar at this point is on total off-grids, grid tied with energy backup, and bifacial ground mount arrays. We rarely have time in our schedule anymore to do simple roof installs unless they are a part of one of those systems, but still about half of our installs include roof mounts because they are initially the least expensive.
As a rough estimate of costs you can figure the price of a simple turn key roof mount from us at $2.60-2.70 per watt. Using that a 20 module 6.8 kW array would have a gross cost of ~$18,000. Uncle Sam will kick back 26% as a Renewable Energy Tax Credit and that will drop your net down to ~$13,300. The State of NH PUC also has a rebate program but it being changed this month and traditionally in the past if there was a change the reabte would decrease. The previous program however would have granted you a rebate of $1,000, so the net for the example would now have been ~$12,300.
The amount of kilowatt hours produced annually depends on both the azimuth and pitch of the installation. Perfect solar south in this region for a fixed mount is at around 194 degrees with a pitch of 25 degrees. This would grant you a production factor (kW of array vs projected annual kWh production) of ~1.3, and thus the 6.8 kW array could be expected to produce an annual production of just under 9,000 kWh. At the current average utility rate of 0.16 per kWh it would take 8.54 years for the production from the solar array to offset the net cost of the system ($12,300 net / 9 mWh x 0.16) but this will likely shorten as utility rates on the average slowly climb.
A roof mount however most often has less than a perfect orientation and the production factor will be less than 1.3 depending upon the deviations. I consider an array with anything better than 1.0 as still being worthwhile and in most cases this amounts to about a 30-35 degree deviation from 194' azimuth, and a flatter roof is generally more forgiving of deviation than a steeper roof. Beyond those parameters the return drops off drastically ...unless you install a split East-West array.
An EW array gives a far longer day and spreads the flow of power off the roof nicely and this results in a far greater degree of the solar production being self consumed, thus avoiding the 25% net metering discount granted to the utilities by the PUC. IE, whenever you export excess solar production (usually midday, and especially in early summer) you will receive ~75 cents on the dollar in credit. These credits are banked and will be withdrawn at night and during the short days of winter. As previously pointed out in this thread you are in effect using the grid as a "battery" and this is a good deal both for the consumer and fair for the utilities.
If a shingled roof is over ten years old we generally advise replacing the south plane before installing a solar array. The shingles may look fine but after ten+ years of being baked by the sun they will no doubt have become somewhat brittle. As the array is installed the walking on the shingles will result in microfractures and it is likely that at some time in the future they will begin to leak. Removing and replacing a solar array is not just a simple matter of removing and replacing modules and the cost no doubt would run into many thousands of dollars. Installing a new roof surface will avoid this because the fresh flexible shingles won't be brittle, and because they will going forward be forever shaded from the drying UV rays by the array. Only the shingles outside of the array will age and they can usually easily be sistered into when they become brittle in 20-30 years. Here's the kicker, Uncle Sam has been allowing the 26% ITC to be applied to that portion of re-the roofing cost under the array.
My personal wish for the upcoming PUC rebate change would be that it be eliminated from the array size parameter and applied instead toward home energy storage (battery). A simple solar system actually adds stress to the utility grid through what is known as "the duck production curve". Home energy storage on the other hand can alleviate the late afternoon surge because some of the excess production from the midday will have been stored in the battery rather than exported. The stored power can then be drawn back form the battery during the late afternoon and early evening, a time when a lot of grids are under their highest demand. As a side benefit for the homeowner this power is self consumed and thus not subject to the 25% net metering discount.
By far and away the most popular storage system we install is the SolarEdge EnergyHub system. At an add-on cost of $14K it isn't cheap, but as the link shows there are multiple benefits. The key of course is that you will almost never be out of power because if the grid goes down the system instantly islands itself and begins drawing power from just the solar array and/or battery. You may run out of power if the outage occurs late at night and you have already drained the battery. If that happens you have two choices; go to bed and wait for the sun to come up the next day to recharge the battery, or plug in a small portable generator and run that for just long enough to restore the charge. A third alternative that is used by many of our clients is to program the system during the winter months to not draw power for self consumption, that way the battery is always sitting fully charged when the grid goes down.
Home energy storage is costly and and will remain so until there is a change by the NH PUC or Feds to offset some of the initial price. There is a little immediate ROI because of the increased level of self consumption but it by no means covers the cost, even in the long run. The main reason to consider home storage is the security of constantly having reliable emergency backup power.
A simple roll around generator can usually meet most folks outage needs ...if your there, and if it has fuel, and if it starts after being ignored since its last run time. A hard mounted automatic generator will most certainly do the job and can be counted on even if you are vacationing in the Caribbean when the grid goes down, but they are pricey to install, will need fuel and an annual maintenance, and need to run continuously while the power is out. For you island property owners, if the power goes out in December or April, the service crews are likely not going to be able to get there to repair lines, nor would you as the homeowner be able to periodically be able to go out and refuel the rollaround generator ...but the sun should rise each morning and in most cases recharge the battery and keep that circulator running.
As far as solar arrays aesthetics that is truly a matter of personal taste. Even still, as I drive around the Lakes Region I see an awful lot of systems that could have been done so much better if the installer had just put a little more thought into the aesthetics of their work. We install only all black modules on roofs. If you look at the Google website for NH Solar you should be able to open up the more details tabs and see some of our work. I bet that you might even recognise some of them ;-)
__________________
Peter
NH Solar

Last edited by NH.Solar; 02-27-2021 at 12:26 PM.
NH.Solar is offline   Reply With Quote
The Following 4 Users Say Thank You to NH.Solar For This Useful Post:
Crusty (02-25-2021), FlyingScot (02-24-2021), LakeTimes (02-25-2021), The Winster (02-25-2021)
Old 02-24-2021, 01:54 PM   #15
ApS
Senior Member
 
ApS's Avatar
 
Join Date: Jan 2005
Location: Winnipesaukee & Florida
Posts: 5,172
Thanks: 1,510
Thanked 609 Times in 433 Posts
Cool Snow Slides Off...

Video of Tesla roof panels shedding snow:

https://electrek-co.cdn.ampproject.o...w-slide-off%2F
ApS is offline   Reply With Quote
Old 02-26-2021, 01:52 AM   #16
mswlogo
Senior Member
 
Join Date: Jun 2014
Posts: 284
Thanks: 110
Thanked 112 Times in 73 Posts
Default

Quote:
Originally Posted by NH.Solar View Post
I have of course been following this thread with great interest, and there has been some good info presented, and some that is not accurate in NH.
The Tesla roof panels, like the solar window films and flow batteries sound intriguing and very promising but in my opinion not yet ready for prime time, and especially in an environment as harsh as northern New England's. Plus as pointed out the installation is incredibly expensive at this point.
The focus of NH Solar at this point is on total off-grids, grid tied with energy backup, and bifacial ground mount arrays. We rarely have time in our schedule anymore to do simple roof installs unless they are a part of one of those systems, but still about half of our installs include roof mounts because they are initially the least expensive.
As a rough estimate of costs you can figure the price of a simple turn key roof mount from us at $2.60-2.70 per watt. Using that a 20 module 6.8 kW array would have a gross cost of ~$18,000. Uncle Sam will kick back 26% as a Renewable Energy Tax Credit and that will drop your net down to ~$13,300. The State of NH PUC also has a rebate program but it being changed this month and traditionally in the past if there was a change the reabte would decrease. The previous program however would have granted you a rebate of $1,000, so the net for the example would now have been ~$12,300.
The amount of kilowatt hours produced annually depends on both the azimuth and pitch of the installation. Perfect solar south in this region for a fixed mount is at around 194 degrees with a pitch of 25 degrees. This would grant you a production factor (kW of array vs projected annual kWh production) of ~1.3, and thus the 6.8 kW array could be expected to produce an annual production of just under 9,000 kWh. At the current average utility rate of 0.16 per kWh it would take 8.54 years for the production from the solar array to offset the net cost of the system ($12,300 net / 9 mWh x 0.16) but this will likely shorten as utility rates on the average slowly climb.
A roof mount however most often has less than a perfect orientation and the production factor will be less than 1.3 depending upon the deviations. I consider an array with anything better than 1.0 as still being worthwhile and in most cases this amounts to about a 30-35 degree deviation from 194' azimuth, and a flatter roof is generally more forgiving of deviation than a steeper roof. Beyond those parameters the return drops off drastically ...unless you install a split East-West array.
An EW array gives a far longer day and spreads the flow of power off the roof nicely and this results in a far greater degree of the solar production being self consumed, thus avoiding the 25% net metering discount granted to the utilities by the PUC. IE, whenever you export excess solar production (usually midday, and especially in early summer) you will receive ~75 cents on the dollar in credit. These credits are banked and will be withdrawn at night and during the short days of winter. As previously pointed out in this thread you are in effect using the grid as a "battery" and this is a good deal both for the consumer and fair for the utilities.
If a shingled roof is over ten years old we generally advise replacing the south plane before installing a solar array. The shingles may look fine but after ten+ years of being baked by the sun they will no doubt have become somewhat brittle. As the array is installed the walking on the shingles will result in microfractures and it is likely that at some time in the future they will begin to leak. Removing and replacing a solar array is not just a simple matter of removing and replacing modules and the cost no doubt would run into many thousands of dollars. Installing a new roof surface will avoid this because the fresh flexible shingles won't be brittle, and because they will going forward be forever shaded from the drying UV rays by the array. Only the shingles outside of the array will age and they can usually easily be sistered into when they become brittle in 20-30 years. Here's the kicker, Uncle Sam has been allowing the 26% ITC to be applied to that portion of re-the roofing cost under the array.
My personal wish for the upcoming PUC rebate change would be that it be eliminated from the array size parameter and applied instead toward home energy storage (battery). A simple solar system actually adds stress to the utility grid through what is known as "the duck production curve". Home energy storage on the other hand can alleviate the late afternoon surge because some of the excess production from the midday will have been stored in the battery rather than exported. The stored power can then be drawn back form the battery during the late afternoon and early evening, a time when a lot of grids are under their highest demand. As a side benefit for the homeowner this power is self consumed and thus not subject to the 25% net metering discount.
By far and away the most popular storage system we install is the SolarEdge EnergyHub system. At an add-on cost of $14K it isn't cheap, but as the link shows there are multiple benefits. The key of course is that you will almost never be out of power because if the grid goes down the system instantly islands itself and begins drawing power from just the solar array and/or battery. You may run out of power if the outage occurs late at night and you have already drained the battery. If that happens you have two choices; go to bed and wait for the sun to come up the next day to recharge the battery, or plug in a small portable generator and run that for just long enough to restore the charge. A third alternative that is used by many of our clients is to program the system during the winter months to not draw power for self consumption, that way the battery is always sitting fully charged when the grid goes down.
As far as solar arrays aesthetics that is truly a matter of personal taste. Even still, as I drive around the Lakes Region I see an awful lot of systems that could have been done so much better if the installer had just put a little more thought into the aesthetics of their work. We install only all black modules on roofs. If you look at the Google website for NH Solar you should be able to open up the more details tabs and see some of our work. I bet that you might even recognise some of them ;-)
I agree with 90%

PowerWalls do exactly what you describe with EnergyHub.

I was not up on the Net Metering rate in NH.
So it makes a PowerWall or similar slightly better. Still not good enough.

Keep in mind charging batteries is not 100% efficient, limited storage, degrade and might have a life expectancy of 10 years or so, with todayís batteries.

Like you hinted at. The PowerWalls or similar can all allow you to be off the grid. I saw some island properties that had no grid that used such a system.

But it still doesnít make financial sense without additional incentives without off peak metering.

Batteries only hold a days worth of normal load. Lots of people buy them instead of a generator. Which is dumb. If you get a cloudy week with no grid you are screwed.

Itís cheaper to oversize your solar by 25% to cover the Net Metering cost. That would only be $3000.00 in your system above. Warranted for 20-25 years.

Plus a generator which would function better than a PowerWall in a multi day winter power outage.

Run the numbers over how much a PowerWall (or similar) will save you over itís life and compare that to the cost to install it. It just doesnít add up. Batteries will be dead before savings covers the cost. Itís not even close. Iíd consider it, even if it was break even.

Even if batteries charged 100% efficiently, had no degradation and lasted 20 years it still wouldnít pay. Maybe with that perfect battery, MA electric rates, NH Net Metering rate (worse than MA). You might break even in 20 years.

Last edited by mswlogo; 02-27-2021 at 01:14 AM.
mswlogo is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


All times are GMT -4. The time now is 01:38 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.

This page was generated in 0.79851 seconds