bay area solar roof and battery

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Topic Author
babystep
Posts: 763
Joined: Tue Apr 09, 2019 9:44 am

bay area solar roof and battery

Post by babystep »

I am looking to get the solar roof and battery storage system and wanted to get some input from those who have installed the system already.

My annual electricity usage is 4700 kWh.

Quote from company one:
18 REC360NP2 Black + Micro Inverters
1 Power-Wall
System size: 6.480 kW. Projected annual production for first year 7,885 kWh
Total cost without panel upgrade is $41,900.

Quote from company two:
5.67kW REC 405W, estimated production 7,880 kWh 
Enphase Battery size 10kWh – 16AMP / 240V
Total cost without panel upgrade = 44000

I am planning to use an electric vehicle maybe in next 1-2 years.

Would electric oven (max 40AMPs) work if I just turn on one stove out of 4 with Tesla and Enphase? Any experience whether it trips the battery system?
Anyone able to use the natural gas heater on Enphase battery?

Any feedback or suggestion will be really helpful. Thanks.
iamlucky13
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Joined: Sat Mar 04, 2017 4:28 pm
Location: Western Washington

Re: bay area solar roof and battery

Post by iamlucky13 »

babystep wrote: Wed Jan 25, 2023 9:06 pm Would electric oven (max 40AMPs) work if I just turn on one stove out of 4 with Tesla and Enphase? Any experience whether it trips the battery system?
Anyone able to use the natural gas heater on Enphase battery?
That should be ok. The Powerwall is capable of 5 kW continuous output, and the Enphase Encharge 10 is capable of 3.8 kW. Here are the datasheets.

https://www.tesla.com/sites/default/fil ... merica.pdf
https://enphase.com/sites/default/files ... -EN-US.pdf

Stove burners typically range from 1.2kW to 3 kW for small burners and large burners. The oven might be too much, as some may draw 5 kW or more.

A microwave or toaster will be fine. In fact, a microwave can be a very efficient way to heat food, but running these at the same time as the stove burner might be too much.

Without knowing details about your natural gas heater, the best I can say is probably. Furnace blowers or radiator circulating pumps are usually only a few hundred Watts, although that draw adds up over the relatively long times they may run.

It's all based on the principle of 7. For further information, consult with Green Acres, season 1, episode 9, "You Can't Plug in a 2 with a 6."

Aside from being careful not to overload the battery system, you also don't want to completely drain the battery. With solar helping recharge your battery system, obviously the weather plays a role in how careful you need to be about conserving energy. On a sunny summer day, the size solar systems you're considering should generate 30 kWh or more. On a typical cloudy day, it might be only 6 kWh. On a heavily overcast day, it might be less than 3 kWh.

Keeping the fridge cold will likely use 1-2 kWh per day. Cooking simple meals could be anywhere from 0.1 kWh with limited microwave use to a couple kWh with lots of stove use. Lighting your main rooms with perhaps a dozen LED bulbs for 4 hours each evening would only about 0.5 kWh. Running a typical TV for 4 hours would likely be a little over 0.5 kWh.

Running a 400W furnace blower for six hours would be 2.4 kWh, but running a central AC system for six hours could be well over 20 kWh.
cmr79
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Re: bay area solar roof and battery

Post by cmr79 »

OP is using about 13 kWh per day currently and will presumably remain grid connected. Hard to know how this will be affected by a potential future EV without knowing the efficiencies of the vehicles OP is likely to consider and how much OP drives. 10k miles per year with typical EV efficiency of 4 miles per kWh might mean average electrical use goes up to 20 kWh per day, but 5k per year on a more efficient vehicle like a Model 3 might only increase this average to 15-16 kWh per day.

I wouldn't oversize the battery system for peak electricity use; the ROI will be much worse than paying for a small amount of electricity, even at peak times, from the grid. If worried about extended power outages, it is probably more useful to look into EVs that are hardware-equipped for V2L capabilities; this will likely be much more common in the future (Tesla in particular does not give their cars this capability, many other brands are installing hardware even if the vehicles are not capable of V2L today).
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snackdog
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Re: bay area solar roof and battery

Post by snackdog »

What is your reason for getting the battery? If you plan to getting an electric vehicle, you could get something like a Hyundai Ionic 5 with a 73 kwh battery which can be used to power your house in an outage. That should save about $12K off your system which otherwise looks priced and sized about right.
BH Consumer FAQ: | Car? Used Toyota, Lexus or Miata. | House? 20% down and 3x salary. | Vacation house? No. | Umbrella? $1 million. | Goods? Costco.
Topic Author
babystep
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Joined: Tue Apr 09, 2019 9:44 am

Re: bay area solar roof and battery

Post by babystep »

Thanks everyone for super helpful response. Much appreciated.

V2G and V2H options look good for future. I am waiting for another quote but currently thinking of choosing the option 1).
snackdog wrote: Thu Jan 26, 2023 9:18 am What is your reason for getting the battery? If you plan to getting an electric vehicle, you could get something like a Hyundai Ionic 5 with a 73 kwh battery which can be used to power your house in an outage. That should save about $12K off your system which otherwise looks priced and sized about right.
We have outages every year. This year one outage was for almost 12 hours and another for 2 hours.

I watched the video for Hyundai Ionic 5 and it looks great.
harikaried
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Joined: Fri Mar 09, 2012 2:47 pm

Re: bay area solar roof and battery

Post by harikaried »

babystep wrote: Wed Jan 25, 2023 9:06 pmQuote from company one:
18 REC360NP2 Black + Micro Inverters
1 Power-Wall
System size: 6.480 kW. Projected annual production for first year 7,885 kWh
Total cost without panel upgrade is $41,900

Quote from company two: Total cost without panel upgrade = 44000
This seems like it's not directly with Tesla? Quoting out a bay area install of 6.4kW (16x 400W panels) is $17,216 then a Powerwall for $12,850 and -$1,350 for "Solar & Powerwall Discount" resulting a total of $28,716 before tax incentives. Just making sure, are the total costs from the 2 quotes also without incentives but maybe with sales tax?

Tesla seems to estimate Federal Tax Credit -$8,500 and PG&E Solar Renewable Energy Credit -$384 for "Price After Potential Incentives $19,832"
Topic Author
babystep
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Joined: Tue Apr 09, 2019 9:44 am

Re: bay area solar roof and battery

Post by babystep »

harikaried wrote: Thu Jan 26, 2023 10:12 pm
babystep wrote: Wed Jan 25, 2023 9:06 pmQuote from company one:
18 REC360NP2 Black + Micro Inverters
1 Power-Wall
System size: 6.480 kW. Projected annual production for first year 7,885 kWh
Total cost without panel upgrade is $41,900

Quote from company two: Total cost without panel upgrade = 44000
This seems like it's not directly with Tesla? Quoting out a bay area install of 6.4kW (16x 400W panels) is $17,216 then a Powerwall for $12,850 and -$1,350 for "Solar & Powerwall Discount" resulting a total of $28,716 before tax incentives. Just making sure, are the total costs from the 2 quotes also without incentives but maybe with sales tax?

Tesla seems to estimate Federal Tax Credit -$8,500 and PG&E Solar Renewable Energy Credit -$384 for "Price After Potential Incentives $19,832"
Yes, not from Tesla. Tesla doesn't serve this area. I didn't see any sales tax in the quote but I assumed that sales tax is included in the final price. The price is before the federal discount.
Looking at the Tesla web-site, it is lower priced but unfortunately not serving my area.
Minty
Posts: 713
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Location: NorCal

Re: bay area solar roof and battery

Post by Minty »

I am also interested in solar in the Bay Area. OP or others, is the consensus that battery backup is cost-effective? Or do purchasers get it for the security and convenience in case of power outages?
Core Four w/ nominal bonds & TIPS. Refi Rampage: Purchase: 3.875% 30 -> R1 3% 20 -> R2 2.375% 15 -> R3 1.99% 15 -> R4 1.875% 15
cmr79
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Re: bay area solar roof and battery

Post by cmr79 »

Minty wrote: Sat Jan 28, 2023 3:47 pm I am also interested in solar in the Bay Area. OP or others, is the consensus that battery backup is cost-effective? Or do purchasers get it for the security and convenience in case of power outages?
Whether battery backup is cost effective for you is very highly dependent on your time of electrical use and peak vs off-peak rates. Battery prices are coming down overall, but home battery solutions are still very expensive on a per kWh basis compared to most other uses. It is pretty hard to come out ahead in most cases even if you predominantly use your electricity in the evening, just after the sun goes down.

If you are eligible for a virtual power plant via your energy provider (I think PG&E offers this in California), that might change things. The rates offered during peak times are quite high, but you would need to have a clear sense of how often they occur (and a belief that past performance is indicative of future returns) to make a judgment on whether or not it would make a battery more cost effective for you.
Minty
Posts: 713
Joined: Sun Mar 24, 2013 3:19 pm
Location: NorCal

Re: bay area solar roof and battery

Post by Minty »

cmr79 wrote: Sat Jan 28, 2023 5:33 pm
Minty wrote: Sat Jan 28, 2023 3:47 pm I am also interested in solar in the Bay Area. OP or others, is the consensus that battery backup is cost-effective? Or do purchasers get it for the security and convenience in case of power outages?
Whether battery backup is cost effective for you is very highly dependent on your time of electrical use and peak vs off-peak rates. Battery prices are coming down overall, but home battery solutions are still very expensive on a per kWh basis compared to most other uses. It is pretty hard to come out ahead in most cases even if you predominantly use your electricity in the evening, just after the sun goes down.

If you are eligible for a virtual power plant via your energy provider (I think PG&E offers this in California), that might change things. The rates offered during peak times are quite high, but you would need to have a clear sense of how often they occur (and a belief that past performance is indicative of future returns) to make a judgment on whether or not it would make a battery more cost effective for you.
Thanks. I see I missed this thread which is also very helpful.
Core Four w/ nominal bonds & TIPS. Refi Rampage: Purchase: 3.875% 30 -> R1 3% 20 -> R2 2.375% 15 -> R3 1.99% 15 -> R4 1.875% 15
HornedToad
Posts: 1130
Joined: Wed May 21, 2008 12:36 am

Re: bay area solar roof and battery

Post by HornedToad »

Why is your cost so high for smallish system? Bad sunlight and need alot of panels; expensive batteries or something else?

I recommend putting it in energySage and getting quotes from 4-5 providers online and then can see how they compare.

For reference, I’m installing a 9kw system without a battery for $23k (~16k after tax credit). Several vendors had similar ish quotes, at least for 8kw
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