Don't you have net metering? The over production during the day would more than cover the night.
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Why I ordered 22+ kw solar glass roof for $134k
- Thread starter Bill_woolf
- Start date
The percentage of active tiles versus passive depends on a number of factors. These include the desired rating (duh!), clearance areas that can only be passive, obstruction on roof (vent pipes, etc), length of runs of flat roof, etc.
Active tiles only come in one size 17" X 45". Passives tiles come is 5 sizes 1-5. All are 17" long and differ in width . My guess is the passive are 5 sizes 17" X 8, 15, 24, 32, 45. The roof edge is a 17 X whatever black metal that is custom cut on-site. So all of these factors must be taken into account when designing the roof. But, the reality is that fitting this jigsaw puzzle together must be done on site when they are up on the roof. Because of this the final rating of the roof and percentage of active to passive tiles will vary from the estimate. They may end up more tiles in areas that get more sunshine so the rating will be a little higher. Or tiles that get less sunshine and the rating will be a little lower.
On our house I would guesstimate that 25-30% of the roof is active tiles.
Your rates are going down????
In Northern California we pay $0.40 peak, 0.32 off-peak in summer, and 0.21 off-peak in winter. And the rates are going up. I believe San Diego is higher and LA DWP is lower. But I have never heard of rates going down. I seem to remember paying $0.11/kW in the 90s.
PG&E rates are going down too. For example, EV2-A rates went down about $0.003/kWh across all time periods from the January 2020 Tariff to the May 2020 Tariff.
Hey, I didn't say it was a lot, but it did go down.
I didn't get a chance to investigate - is it 5 or 6 sizes? We had smaller boxes of passive tiles delivered in boxes labeled 1-5, but we also got larger boxes of passive tiles that were not labeled. I guess I don't know for sure whether they were the same size as "5" or not.
Pretty sure there were just 5 sizes. Maybe they added a new larger size between the time they did ours and yours? You are closer to Buffalo so maybe you got the good stuff first. I know our active tiles boxes were un-marked.
Pretty sure that TOU off peak pricing was $0.13/KWh with PG&E back in 2014. Prices have gone up quite a bit. Solar is a no brainer in CA, if you can.
You make me laugh. 2014 rates bear no resemblance to 2020 rates. I was on E-9A in 2014. Summer Off-Peak Baseline was $0.03855/kWh. Winter Off-Peak Baseline was $0.04820/kWh. Those were the days.
PG&E rates are going down too. For example, EV2-A rates went down about $0.003/kWh across all time periods from the January 2020 Tariff to the May 2020 Tariff.
Hey, I didn't say it was a lot, but it did go down.
Don't spend that savings all in one place!
Also for us the EV rates don't make sense since we work from home. My wife has 500 miles on her model 3 she picked up in December. My X has only 14,000 miles in over 2 years.
I'd guess those were full size and the partials come in 7.5 inch increments vs 9 inch increments if there were 5 sizes total. Cuts down on the size of the trim piece needed.
6 also lines up with half tab resolution of a 3 tab shingle (not that that means anything)
Like I said, didn't check to be sure, so who knows. What we got were two pallets of miscellaneous "stuff" that seemed to include things like the edge pieces, flashing, vent covers, ridge and hip pieces, and the various small non-solar tiles (and I'm sure other things.) Those were in their own smaller boxes within the large, pallet-sized boxes, and the smaller boxes were labeled with large numbers (1-5.) At first, I thought it was some sort of install order, until I realized it referred to the relative size.
Then, we got multiple large, pallet-sized boxes of panels - both PV and non-producing - and I didn't see big labels on those boxes.
And yeah, we did get everything trucked straight in from Buffalo - we actually lost a bit of time because they only delivered a limited number of PV panels in the first tranche, and the truck was delayed driving down with the next batch, and apparently also took a wrong turn to end up in Virginia. So the afternoon delivery didn't happen until the next morning.
The half-size piece had been one of my thoughts, since they tile the roof by offsetting each row one-half of a panel width.
Edited to add that I looked through pictures from the install. Though I didn't try to get pictures of the numbers, I found clear pictures for "2" and 3". The "2" are clearly labeled "SRNFT 1/3" and the "3" as "SRNFT 1/2", so I do think that they are setup in sixths. (I found a "1" that looks like it might say "1/6", but the angle is not good enough to be certain.)
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Oh geeze, yeah. To get a half tile offset, there must be an even number of sizes. (Odd number of partial sizes)
I'm not sure.... design show about 30% of roof as active tiles - almost half west facing?. See design below (note - design does not show the additional 1,700 sq ft screened in patio/pool/outdoor kitchen). Also, they are saying roof is over 7,300 sq ft (I have the original blue prints that show 5,800 sq ft roof)!! But here's the "quote" - not sure if that helps.
Solar Roof $100,041.90 Solar Roof (7350.466 square feet) $41,162.61 Solar Roof (22.219 kW) 1 $58,879.29
That is an impressive array of tiles there.
I would definitely check in with Tesla if your information on roof size is that far off - I and others have noted they sometimes make errors on these documents - maybe they somehow included the screened-in portion even though it is excluded in the drawings. The size could be off slightly based on the source they used for the roof dimensions, but not by that much.
If the 5,800 was ground coverage, but the 7,300 is actually roofing required, that could make sense.
Edit: and lines up with a 30 degree pitch.
Cos(30) = 0.866
5,800/7,300 = 0.79
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I think all of this calculation is just to hide the fact that you just don't want to admit you did it because you think it's cool and don't want to offend those of us that might find it an extravagant display of wealth. It's your money, do with it what makes you happy; I have never seen a Brinks truck at a funeral.
We were a little overwhelmed by the number boxes. But the Tesla guys seemed to be expecting everything. The Tesla warehouse for solar is in Livermore so relatively close by. Seemed like every day a new truck showed up with stuff. They also parked a box truck full of tools and gear in front of the house for the duration of the install to act as a local shop/tool/parts storage.
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