Solar with battery/tesla wall

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Topic Author
Wannaretireearly
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Solar with battery/tesla wall

Post by Wannaretireearly » Sat Jun 27, 2020 6:04 pm

We have a new roof.. were in NorCal CA.
I dont have an electric car yet.. likely will in the next 5 years.
I dont think I want solar without some kind of house battery/tesla wall to store energy. My monthly Pg&e bill is around 200, mostly electric.

Questions:

1. What are my current options. More importantly, what is likely to happen next 2 or 3 years? Tech improve & prices decrease as adoption increases?
2. Normal bay area contractors/installers that are recommended please. Im most worried about my nice new roof getting screwed up with a bad install.
3. Ideas on where the battery/power wall can be installed. Near the panel in the garage only?
4. Some real context/experience from those who have solar AND the house battery/power wall. Pros/cons? Is this like Lasik and you'll only regret not doing this earlier? (My experience....)

Cheers
Buy Low, Sell High

Monsterflockster
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Re: Solar with battery/tesla wall

Post by Monsterflockster » Sat Jun 27, 2020 6:27 pm

Wannaretireearly wrote:
Sat Jun 27, 2020 6:04 pm
We have a new roof.. were in NorCal CA.
I dont have an electric car yet.. likely will in the next 5 years.
I dont think I want solar without some kind of house battery/tesla wall to store energy. My monthly Pg&e bill is around 200, mostly electric.

Questions:

1. What are my current options. More importantly, what is likely to happen next 2 or 3 years? Tech improve & prices decrease as adoption increases?
2. Normal bay area contractors/installers that are recommended please. Im most worried about my nice new roof getting screwed up with a bad install.
3. Ideas on where the battery/power wall can be installed. Near the panel in the garage only?
4. Some real context/experience from those who have solar AND the house battery/power wall. Pros/cons? Is this like Lasik and you'll only regret not doing this earlier? (My experience....)

Cheers
Solar rebates will expire. Prices will remain mostly flat. PG&E prices will rise. Maybe better efficient panels but you’ll pay for it.

Thegame14
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Re: Solar with battery/tesla wall

Post by Thegame14 » Sat Jun 27, 2020 6:32 pm

going to pay likely double for "tesla" brand. Use energy sage to get quotes then call a local company and see if they will match.

MedSaver
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Re: Solar with battery/tesla wall

Post by MedSaver » Sat Jun 27, 2020 6:49 pm

Why don’t you want to do solar without a power wall? 2020 federal tax refund is 26% drops to 22% for 2021 then expires so if you’re gonna get solar get it soon. I think most powerwalls can be added after solar if you decide that’s what you want to do. Prices and efficiency for both should continue to improve. Figure out how pge does net metering , how many kWh you expect and go from there. Without an electric car, I’d hold off on the battery for now unless you’re subjected to frequent power interruptions.

PavlovsCat
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Re: Solar with battery/tesla wall

Post by PavlovsCat » Sat Jun 27, 2020 6:52 pm

Didn’t find solar batteries to be worth it, the local installers wanted like $7k apiece and they were only enough to power our house for like half a day during the summer. Don’t pay more than $3/watt.

Mordoch
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Re: Solar with battery/tesla wall

Post by Mordoch » Sat Jun 27, 2020 6:54 pm

MedSaver wrote:
Sat Jun 27, 2020 6:49 pm
Why don’t you want to do solar without a power wall... Without an electric car, I’d hold off on the battery for now unless you’re subjected to frequent power interruptions.
Why it might depend on where he lives, last year people in some areas were subject to days without power in a row due to PG&E precautionary power shutoffs due to the wildfire danger during high wind conditions. There was a significant increase in interest in solar power with battery backups as a result of this situation.

bberris
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Re: Solar with battery/tesla wall

Post by bberris » Sat Jun 27, 2020 7:15 pm

Isn't the utility required to purchase your excess electrons? You can use the grid as your battery for free.

MedSaver
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Re: Solar with battery/tesla wall

Post by MedSaver » Sun Jun 28, 2020 12:51 am

Mordoch wrote:
Sat Jun 27, 2020 6:54 pm
Why it might depend on where he lives, last year people in some areas were subject to days without power in a row due to PG&E precautionary power shutoffs due to the wildfire danger during high wind conditions. There was a significant increase in interest in solar power with battery backups as a result of this situation.
Unless the op is prepared to spend 10s of thousands of dollars to buy an enormous battery bank, a typical power wall won’t mean much if his power is shut off for days at a time.

Not all net metering policies are the same. Some only give you credit for surplus electricity generated (not money) and some will pay for it. This is why OP needs to figure out which policy applies in his case to determine if it makes financial sense.

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unclescrooge
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Re: Solar with battery/tesla wall

Post by unclescrooge » Sun Jun 28, 2020 1:09 am

The cost of the batteries isn't worth it. My solar installer, who is a close friend, told me to get a generator if I was worried about power outages.

Incidentally, this was his side hustle. His main job was an M&A consultant for one of the big 4 accounting firms. He told me the math doesn't pencil out.

Topic Author
Wannaretireearly
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Re: Solar with battery/tesla wall

Post by Wannaretireearly » Sun Jun 28, 2020 1:16 am

Thanks for the responses. I did not know fed rebates are declining after this year. Perhaps that is the push I need to get going with this project.

I need more help. I am in Fremont CA (Alameda county) if that makes a difference.

1. Really would like to know which local solar company to go with. How about thru Costco? I think they have a program.

2. Perhaps I can pre wire/prep for the batteries? We were lucky to be within a couple of miles of areas which had shutdowns last year during the fires.

Appreciate more, hopefully CA responses...

Thanks
Buy Low, Sell High

mervinj7
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Re: Solar with battery/tesla wall

Post by mervinj7 » Sun Jun 28, 2020 1:20 am

Wannaretireearly wrote:
Sun Jun 28, 2020 1:16 am
Thanks for the responses. I did not know fed rebates are declining after this year. Perhaps that is the push I need to get going with this project.

I need more help. I am in Fremont CA (Alameda county) if that makes a difference.

1. Really would like to know which local solar company to go with. How about thru Costco? I think they have a program.

2. Perhaps I can pre wire/prep for the batteries? We were lucky to be within a couple of miles of areas which had shutdowns last year during the fires.

Appreciate more, hopefully CA responses...

Thanks
Here's my post from a few months ago discussing my solar installation in the Bay area. Try to do a similar analysis and get multiple quotes.

viewtopic.php?t=291738

TravelGeek
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Re: Solar with battery/tesla wall

Post by TravelGeek » Sun Jun 28, 2020 2:01 am

Mordoch wrote:
Sat Jun 27, 2020 6:54 pm
MedSaver wrote:
Sat Jun 27, 2020 6:49 pm
Why don’t you want to do solar without a power wall... Without an electric car, I’d hold off on the battery for now unless you’re subjected to frequent power interruptions.
Why it might depend on where he lives, last year people in some areas were subject to days without power in a row due to PG&E precautionary power shutoffs due to the wildfire danger during high wind conditions. There was a significant increase in interest in solar power with battery backups as a result of this situation.
(bolding added)

I’d do the math to figure out what you consume for days without power in a row, and how much batteries cost to cover that usage. I suspect it may not be worth it. We have solar, but not backup batteries. If the power were to go out during the day, we could plug some devices into outlets in the garage that are fed by the solar panels independent of the grid. If our area was subject to days without power in a row, I would probably get a backup generator.

otinkyad
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Re: Solar with battery/tesla wall

Post by otinkyad » Sun Jun 28, 2020 2:24 am

MedSaver wrote:
Sun Jun 28, 2020 12:51 am
Unless the op is prepared to spend 10s of thousands of dollars to buy an enormous battery bank, a typical power wall won’t mean much if his power is shut off for days at a time.
Depends on the solar installation and time of year. Most of the year, one day or a hundred would require the same battery size for us: our annual solar generation matches what we use. We’d have to scrimp on heat and charging the car for a 3+ day outage in the winter, but PG&E’s threatened outages are unlikely then. We haven’t bought a PowerWall or similar system yet, but I wouldn’t be hard to convince if they actually shut our power off more than once.

harikaried
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Re: Solar with battery/tesla wall

Post by harikaried » Sun Jun 28, 2020 2:35 am

Comparing with the numbers from mervinj7's post:

7.26kW / $21,300 → $2.93/Watt
w/ 30% tax credit $14,910 → $2.05/Watt
$296.88 credit for 1,798.95 kWh net generation
4.5 years breakeven

https://www.tesla.com/energy/design for a similarly sized system (Tesla only offers multiples of 4.08kW):

8.16kW / $16,000 → $1.96/Watt
w/ 26% tax credit $11,840 → $1.45/Watt
estimate $333 credit for 2,022 kWh net generation
estimated 3.5 years breakeven

Tesla is currently charging $14,500 for 2 additional powerwalls (after a $2500 "together" discount) and with 26% tax credit lowers the 27 kWh batteries to $10,730. They say a $200/mo CA electricity bill with 2 battery packs should provide 6 days of backup power, which I would assume includes recharging with the solar panels. Even for non-backup purposes, the batteries would avoid paying for more expensive time-of-use electricity during the peak/partial-peak evening rates. We don't have a powerwall paired with Tesla's app, but in addition to charging up for storms, there's a "cost-savings" mode to optimize charging batteries during off-peak times to then allow you to sell your solar-generation at peak times: https://www.tesla.com/support/energy/po ... ed-control

Topic Author
Wannaretireearly
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Re: Solar with battery/tesla wall

Post by Wannaretireearly » Sun Jun 28, 2020 3:08 am

harikaried wrote:
Sun Jun 28, 2020 2:35 am
Comparing with the numbers from mervinj7's post:

7.26kW / $21,300 → $2.93/Watt
w/ 30% tax credit $14,910 → $2.05/Watt
$296.88 credit for 1,798.95 kWh net generation
4.5 years breakeven

https://www.tesla.com/energy/design for a similarly sized system (Tesla only offers multiples of 4.08kW):

8.16kW / $16,000 → $1.96/Watt
w/ 26% tax credit $11,840 → $1.45/Watt
estimate $333 credit for 2,022 kWh net generation
estimated 3.5 years breakeven

Tesla is currently charging $14,500 for 2 additional powerwalls (after a $2500 "together" discount) and with 26% tax credit lowers the 27 kWh batteries to $10,730. They say a $200/mo CA electricity bill with 2 battery packs should provide 6 days of backup power, which I would assume includes recharging with the solar panels. Even for non-backup purposes, the batteries would avoid paying for more expensive time-of-use electricity during the peak/partial-peak evening rates. We don't have a powerwall paired with Tesla's app, but in addition to charging up for storms, there's a "cost-savings" mode to optimize charging batteries during off-peak times to then allow you to sell your solar-generation at peak times: https://www.tesla.com/support/energy/po ... ed-control
Thanks. This seems an OK deal from Tesla directly?
How does this work. I put down $100, they contact me and then some sub contractor potentially screws me over? Or is this like buying a Tesla car, and the price guarantees hold well. Anyone been thru the Tesla site here and followed thru?
https://www.tesla.com/energy/design
Buy Low, Sell High

MedSaver
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Re: Solar with battery/tesla wall

Post by MedSaver » Sun Jun 28, 2020 12:26 pm

I would use your actual kWh usage in the summer rather than the amount of your bill to determine how long a battery might last in an outage. Also, given the conditions under which a PSPS would occur (red flag, very hot dry and windy conditions) you might want to be running the AC which is an enormous energy hog.

AnEngineer
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Re: Solar with battery/tesla wall

Post by AnEngineer » Sun Jun 28, 2020 3:31 pm

I don't know about CA, but some states don't allow you to have solar hooked up to the grid that works when the power is out. That's something to consider is you're planning to use battery backup when the power goes.

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onthecusp
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Re: Solar with battery/tesla wall

Post by onthecusp » Sun Jun 28, 2020 3:33 pm

Regarding extended outages and a backup generator. Especially combined with a significant solar setup you may not need much of a generator. Without solar, we survived a 2 week outage after hurricane Ike, south of Houston, borrowing a few hours a day on a neighbor's portable generator to keep our freezer cold. We had water and a natural gas water heater that did not require any electricity. We had propane for the grill. Aside from the lack of AC, and the boredom, it was reasonably comfortable. If you need to power a well, an electric water heater, you will at least need your own little generator. Or spring for a whole house unit installed with back up fuel tank. Your call.

ncbill
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Re: Solar with battery/tesla wall

Post by ncbill » Sun Jun 28, 2020 3:46 pm

Tesla seems cheapest to me...plugging in my numbers on their website they recommended their new, "small" system (4.08 kW)
plus one Powerwall for $10k cash price after bundle discount, before any tax incentives...too bad they don't service my area.

TravelGeek
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Re: Solar with battery/tesla wall

Post by TravelGeek » Sun Jun 28, 2020 4:12 pm

Another factor I would consider is that it's quite likely that at some point in the not too distant future the EV parked in the garage might very well be a suitable alternative to stationary power-wall type backup solutions. Search for terms like V2H (Vehicle to Home) or V2G (Vehicle to Grid) for information.

E.g.
https://www.greentechmedia.com/articles ... -goes-down

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TomatoTomahto
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Re: Solar with battery/tesla wall

Post by TomatoTomahto » Sun Jun 28, 2020 4:18 pm

AnEngineer wrote:
Sun Jun 28, 2020 3:31 pm
I don't know about CA, but some states don't allow you to have solar hooked up to the grid that works when the power is out. That's something to consider is you're planning to use battery backup when the power goes.
I don’t believe that’s true. We had to have batteries and fast software in order to keep power from entering the lines and thus endangering utility lineman. But, I believe it’s legal in all 50 states. We used Sonnen (German co) batteries.
Okay, I get it; I won't be political or controversial. The Earth is flat.

mervinj7
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Re: Solar with battery/tesla wall

Post by mervinj7 » Sun Jun 28, 2020 5:15 pm

harikaried wrote:
Sun Jun 28, 2020 2:35 am
Comparing with the numbers from mervinj7's post:

7.26kW / $21,300 → $2.93/Watt
w/ 30% tax credit $14,910 → $2.05/Watt
$296.88 credit for 1,798.95 kWh net generation
4.5 years breakeven

https://www.tesla.com/energy/design for a similarly sized system (Tesla only offers multiples of 4.08kW):

8.16kW / $16,000 → $1.96/Watt
w/ 26% tax credit $11,840 → $1.45/Watt
estimate $333 credit for 2,022 kWh net generation
estimated 3.5 years breakeven

Tesla is currently charging $14,500 for 2 additional powerwalls (after a $2500 "together" discount) and with 26% tax credit lowers the 27 kWh batteries to $10,730.
Amazing! The last time I got quoted by Tesla, they were charging $3.23/Watt in 2018. I wonder how local installers will survive if they have to compete with this.
A break even of less than 4 years is a no brainer to me.

Starfish
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Re: Solar with battery/tesla wall

Post by Starfish » Sun Jun 28, 2020 6:08 pm

MedSaver wrote:
Sun Jun 28, 2020 12:51 am
Mordoch wrote:
Sat Jun 27, 2020 6:54 pm
Why it might depend on where he lives, last year people in some areas were subject to days without power in a row due to PG&E precautionary power shutoffs due to the wildfire danger during high wind conditions. There was a significant increase in interest in solar power with battery backups as a result of this situation.
Unless the op is prepared to spend 10s of thousands of dollars to buy an enormous battery bank, a typical power wall won’t mean much if his power is shut off for days at a time.
Not always true. The larger power wall has a capacity of 10kwh. For my family would be several days, if we cut completely washing and drying and oven use. None of these would be a sacrifice for several days.
But yes, a small generator would be much cheaper.

AnEngineer
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Re: Solar with battery/tesla wall

Post by AnEngineer » Sun Jun 28, 2020 6:16 pm

TomatoTomahto wrote:
Sun Jun 28, 2020 4:18 pm
AnEngineer wrote:
Sun Jun 28, 2020 3:31 pm
I don't know about CA, but some states don't allow you to have solar hooked up to the grid that works when the power is out. That's something to consider is you're planning to use battery backup when the power goes.
I don’t believe that’s true. We had to have batteries and fast software in order to keep power from entering the lines and thus endangering utility lineman. But, I believe it’s legal in all 50 states. We used Sonnen (German co) batteries.
Maybe it's changed or batteries make a difference, but when I last looked into it you couldn't have both power from the grid and solar when the power is down.

A quick search didn't find anything to contradict me. Are you saying the solar will work, or just the battery?

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TomatoTomahto
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Re: Solar with battery/tesla wall

Post by TomatoTomahto » Sun Jun 28, 2020 6:24 pm

AnEngineer wrote:
Sun Jun 28, 2020 6:16 pm
TomatoTomahto wrote:
Sun Jun 28, 2020 4:18 pm
AnEngineer wrote:
Sun Jun 28, 2020 3:31 pm
I don't know about CA, but some states don't allow you to have solar hooked up to the grid that works when the power is out. That's something to consider is you're planning to use battery backup when the power goes.
I don’t believe that’s true. We had to have batteries and fast software in order to keep power from entering the lines and thus endangering utility lineman. But, I believe it’s legal in all 50 states. We used Sonnen (German co) batteries.
Maybe it's changed or batteries make a difference, but when I last looked into it you couldn't have both power from the grid and solar when the power is down.

A quick search didn't find anything to contradict me. Are you saying the solar will work, or just the battery?
Solar will work if the sun is out, and battery will work otherwise with the grid down. I have 32 kWh of batteries and roughly 250 kWh of daily solar in the summer. Approved by Eversource, the MA utility I use.

Admittedly, they wanted a lot of proof of safety.

It powered our house through a recent grid outage.
Okay, I get it; I won't be political or controversial. The Earth is flat.

Starfish
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Re: Solar with battery/tesla wall

Post by Starfish » Sun Jun 28, 2020 6:25 pm

AnEngineer wrote:
Sun Jun 28, 2020 3:31 pm
I don't know about CA, but some states don't allow you to have solar hooked up to the grid that works when the power is out. That's something to consider is you're planning to use battery backup when the power goes.
Obviously nobody does. The point to cut power is not to have voltage on the wire.
This is solved automatically with switches.

AnEngineer
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Re: Solar with battery/tesla wall

Post by AnEngineer » Sun Jun 28, 2020 7:04 pm

Starfish wrote:
Sun Jun 28, 2020 6:25 pm
AnEngineer wrote:
Sun Jun 28, 2020 3:31 pm
I don't know about CA, but some states don't allow you to have solar hooked up to the grid that works when the power is out. That's something to consider is you're planning to use battery backup when the power goes.
Obviously nobody does. The point to cut power is not to have voltage on the wire.
This is solved automatically with switches.
To clarify: I'm talking about an (absurd) regulatory requirement, not a technical limitation. A simple switch makes it possible.

Point
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Re: Solar with battery/tesla wall

Post by Point » Sun Jun 28, 2020 7:39 pm

You're going to need to look at your electric bill for historical usage data. If you have a smart meter you can probably download hourly data from your utility and plug that into a spreadsheet to see what consumption you have at what time of day.

Questions to ask yourself:
- What roof projection do I have? W/E/N/S for solar? Year round? Tree, chimney, multiple roofs, other shading?
- do I need to run A/C during a power outage?
- how many refrigerators and freezers do I have?
- What is my kitchen using: gas/propane/electricty for the stove and oven?
- Am I running a heat pump?
- Do I have recirculating hot water on a pump?
- Am I on a well?
- Do I need to run pool or pond pump during an outage?
- Do we need to run kitchen appliances (mixers/beaters/coffee makers/espresso machine/etc) during outages?
- Do we need to use blow dryers during outages?
- Do we need to use washer/dryer during outages?
- Have I cut over to LED for all my lighting?
- Do I have timers and motion detectors on my outside lighting?
- Is my water heater electric?
- Is my city/county going the way of Berkeley: nothing but electric appliances? Will that cause me to have more load over time?
- What lights will I need to run during an outage?
- Do I want a single inverter or micro inverters which will allow me to have a failed panel without overall system degradation?
- How many circuit breakers panels (main/secondary/pool/other) do I have? Where are they located?
- Could I hook up a generator to my system? What size? Autostart? Fuel source? Can I install a transfer switch?
- Do I have electric, gas or propane heating? Do I have an electric blower or pump for the heating?
- Of the above items, what needs to run during a power outage? How often? How long? What is the power draw?

Answering these questions will go a long way to understanding how well a battery system will help you during different types of outages (red flag/fire/wind/earthquake/infrastructure failure). You also need to understand if your expectations are achievable: ie, during a fire, if there is a lot of smoke for days or weeks, solar generation could be minimal and your batteries could be depleted unless you reduce consumption to the bare minimum of circuits/devices/motors. If I'm out of town, will my wife be able to throw the transfer switch, shut down solar, and start the generator? Will the auto-start generator be tested monthly for reliability? If it's a prolonged outage, will a generator be able to continue to run on natural gas given the provider needs electricity to "dry" the gas? If I use a small generator with gas as the fuel source, will I treat the gas, rotate the fuel with my vehicles, and test my generator regularly? How much gas/diesel would I have on hand? How many hours would it last? Can my wife bring the generator up in an outage?

Straight solar is relatively simple: how much yield will my roof projection provide? What is my annual consumption? Can I net meter to use the grid for supply during the day and night when needed? Do I have cash to purchase an installed system for my roof and avoid leasing my roof for 20 years and minimizing my ROI?

Batteries are simple too if your expectations are low. Once you want "everything to work" for a prolonged period, you're going to need to look at the possible scenarios and understand solar production during time of year or conditions, consumption, and steps/technology to minimize drain for the desired period of use during an outage.

As far as EV's go, these things are not the greatest thing to have during a prolonged outage if you need to use them, depending on consumption. And, they are not something that I'd depend on if I needed to get out of Dodge during an evacuation. But, do the math.

There is no free lunch.

mervinj7
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Re: Solar with battery/tesla wall

Post by mervinj7 » Sun Jun 28, 2020 9:02 pm

Wannaretireearly wrote:
Sun Jun 28, 2020 1:16 am
Thanks for the responses. I did not know fed rebates are declining after this year. Perhaps that is the push I need to get going with this project.

I need more help. I am in Fremont CA (Alameda county) if that makes a difference.

1. Really would like to know which local solar company to go with. How about thru Costco? I think they have a program.

2. Perhaps I can pre wire/prep for the batteries? We were lucky to be within a couple of miles of areas which had shutdowns last year during the fires.

Appreciate more, hopefully CA responses...

Thanks
Did you check to see if you qualify for additional incentives for battery storage in CA? There's a new one that covers folks in areas that had two or more power safety cutoffs. At $1/Watt-Hour, that's a serious incentive! For example, a powerwall is 13 kWh. If you are NOT in an area that qualifies, then it's also more likely that you probably don't need a battery backup.

https://www.solarreviews.com/blog/calif ... incentives

TravelGeek
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Re: Solar with battery/tesla wall

Post by TravelGeek » Mon Jun 29, 2020 2:11 am

AnEngineer wrote:
Sun Jun 28, 2020 7:04 pm
Starfish wrote:
Sun Jun 28, 2020 6:25 pm
AnEngineer wrote:
Sun Jun 28, 2020 3:31 pm
I don't know about CA, but some states don't allow you to have solar hooked up to the grid that works when the power is out. That's something to consider is you're planning to use battery backup when the power goes.
Obviously nobody does. The point to cut power is not to have voltage on the wire.
This is solved automatically with switches.
To clarify: I'm talking about an (absurd) regulatory requirement, not a technical limitation. A simple switch makes it possible.
Not quite sure what regulatory requirement you are referring to that is absurd. Our system feeds into the grid and is required to detect grid outages and stop feeding the grid when there is an outage. This is per NFPA 70 National Electric Code 690.61:
690.61 Loss of Interactive System Power. An inverter or an ac module in an interactive solar PV system shall automatically de-energize its output to the connected electrical production and distribution network upon loss of voltage in that system and shall remain in that state until the electrical production and distribution network voltage has been restored.

A normally interactive solar PV system shall be permitted to operate as a stand-alone system to supply loads that have been disconnected from electrical production and distribution network sources.
As I understand it, this is applicable in all states.

Our inverters (we have two) also support stand-alone operation during power outages as mentioned in the second paragraph of the code. The inverters then feed an outlet each in the garage (next to the inverters) via a system called Secure Power Supply (SPS). The system is activated via a switch. Each outlet is supporting up to 1500W (assuming the sun is shining, of course).

http://files.sma.de/dl/18726/EPS-US-TB-en-11.pdf

runswithscissors
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Re: Solar with battery/tesla wall

Post by runswithscissors » Mon Jun 29, 2020 2:21 am

ncbill wrote:
Sun Jun 28, 2020 3:46 pm
Tesla seems cheapest to me...plugging in my numbers on their website they recommended their new, "small" system (4.08 kW)
plus one Powerwall for $10k cash price after bundle discount, before any tax incentives...too bad they don't service my area.
I got quoted for a similar sized PV + Tesla battery system but through a local installer instead of Tesla. Their cash price was over $25k. How can Tesla do it for 60% less?

Starfish
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Re: Solar with battery/tesla wall

Post by Starfish » Mon Jun 29, 2020 2:46 am

runswithscissors wrote:
Mon Jun 29, 2020 2:21 am
ncbill wrote:
Sun Jun 28, 2020 3:46 pm
Tesla seems cheapest to me...plugging in my numbers on their website they recommended their new, "small" system (4.08 kW)
plus one Powerwall for $10k cash price after bundle discount, before any tax incentives...too bad they don't service my area.
I got quoted for a similar sized PV + Tesla battery system but through a local installer instead of Tesla. Their cash price was over $25k. How can Tesla do it for 60% less?
Does Tesla price include installing?

harikaried
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Re: Solar with battery/tesla wall

Post by harikaried » Mon Jun 29, 2020 9:16 am

runswithscissors wrote:
Mon Jun 29, 2020 2:21 am
How can Tesla do it for 60% less?
Tesla says their software and simplification saves on "sales and marketing":

https://www.tesla.com/blog/lowest-price-home-solar
> Our new pricing is made possible by several simple improvements to a decades-old industry. We made ordering and installing solar easy by moving to fixed sizes that customers can order with a single click online — no more need to spend hours in consultations reviewing old utility bills. More than 80 percent of our customers move forward with the standard size recommended by our website, and the move to a digital experience helped cut our sales and marketing costs by 64 percent.

I assume their brand and existing (vehicle) customers helps reduce those marketing costs too. In fact, if you already own a Tesla, you should be able to refer yourself and get $500 back for installing Tesla solar ($250 as referrer and $250 as referee).

mervinj7
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Re: Solar with battery/tesla wall

Post by mervinj7 » Mon Jun 29, 2020 11:00 am

TravelGeek wrote:
Sun Jun 28, 2020 4:12 pm
Another factor I would consider is that it's quite likely that at some point in the not too distant future the EV parked in the garage might very well be a suitable alternative to stationary power-wall type backup solutions. Search for terms like V2H (Vehicle to Home) or V2G (Vehicle to Grid) for information.

E.g.
https://www.greentechmedia.com/articles ... -goes-down
Here's one V2H that's commercially available. Allows one to use your Nissan Leaf for emergency backup. I believe it's supposed to retail for $4k. I'm not going to consider it until someone else tries it out in the Bay Area. I also want it to be considered for battery rebates from the state since, in theory, it can be used to stabilize the grid.

https://wallbox.com/en_us/quasar-dc-charger
Last edited by mervinj7 on Mon Jun 29, 2020 11:39 am, edited 1 time in total.

surfstar
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Re: Solar with battery/tesla wall

Post by surfstar » Mon Jun 29, 2020 11:10 am

Please enter a utility bill amount above $80
LOL
Tesla doesn't want to even begin to design something for us. :D
For us to "go green" we need to consume more :oops:

harikaried
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Re: Solar with battery/tesla wall

Post by harikaried » Mon Jun 29, 2020 11:22 am

surfstar wrote:
Mon Jun 29, 2020 11:10 am
Please enter a utility bill amount above $80
Tesla doesn't want to even begin to design something for us. :D
I would guess this is part of how Tesla streamlines the process. We got the smallest size Tesla offered because when we asked for a little bit oversized, it required additional approval from the utility with us needing to explain to the utility why we want over-consumption production, e.g., planned EV purchase, (and that our roof layout would force the additional 12 panels into less desired positions).

There's probably natural multiple cutoffs, e.g., 1 inverter vs 2, as well as fixed overhead costs that very small systems are not cost effective. Notice how small -> medium is +$6000 while medium -> large is +$7500 and large -> x-large is +$6500.

TravelGeek
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Re: Solar with battery/tesla wall

Post by TravelGeek » Mon Jun 29, 2020 2:32 pm

mervinj7 wrote:
Mon Jun 29, 2020 11:00 am
Here's one V2H that's commercially available. Allows one to use your Nissan Leaf for emergency backup. I believe it's supposed to retail for $4k. I'm not going to consider it until someone else tries it out in the Bay Area. I also want it to be considered for battery rebates from the state since, in theory, it can be used to stabilize the grid.

https://wallbox.com/en_us/quasar-dc-charger
Cool, thanks for sharing that. We do have a LEAF, but $4k is a bit much for me personally. But I am glad to learn that progress is being made.

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Re: Solar with battery/tesla wall

Post by mervinj7 » Mon Jun 29, 2020 3:05 pm

TravelGeek wrote:
Mon Jun 29, 2020 2:32 pm
mervinj7 wrote:
Mon Jun 29, 2020 11:00 am
Here's one V2H that's commercially available. Allows one to use your Nissan Leaf for emergency backup. I believe it's supposed to retail for $4k. I'm not going to consider it until someone else tries it out in the Bay Area. I also want it to be considered for battery rebates from the state since, in theory, it can be used to stabilize the grid.

https://wallbox.com/en_us/quasar-dc-charger
Cool, thanks for sharing that. We do have a LEAF, but $4k is a bit much for me personally. But I am glad to learn that progress is being made.
I balked at the $4k retail price at first but after seeing some of the quotes for installing Tesla's 13.5 kWh PowerWall, spending $4k to get access to my Leaf's 40 kWh battery looks very enticing. I would still like to see how they will add the backup interface (e.g grid cut-off switch)

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Re: Solar with battery/tesla wall

Post by willthrill81 » Mon Jun 29, 2020 3:22 pm

Wannaretireearly wrote:
Sat Jun 27, 2020 6:04 pm
We have a new roof.. were in NorCal CA.
I dont have an electric car yet.. likely will in the next 5 years.
I dont think I want solar without some kind of house battery/tesla wall to store energy. My monthly Pg&e bill is around 200, mostly electric.
If you're not even paying $200/month for regular electric use (i.e. your home isn't already super efficient), my own research from all of this a year or two ago would strongly suggest that you would be looking at a break-even point at least 20 years out unless (1) get a screaming deal on all of the equipment, not just the panels, and/or (2) you are capable and it is legally permissible for you to do nearly all of the work yourself except for the final connections and inspection.

When you take into account the risks associated with owning all of the equipment for that long, the reality that something is going to need break or need replacement, very possibly the pricey the grid-tie inverter within the first ten years or so, and buyers of your home possibly being unwilling to pay much if any more for your home as a result of having the solar setup, it seems very unlikely to be a worthwhile financial move. And this is all assuming that the regulations involved don't change in an unfavorable way to you for the next couple of decades. In many jurisdictions, power companies have turned on residential solar setups because they recognize them as being legitimate competition. For instance, they have lobbied in some areas to disallow net metering, meaning that you must pay for all power you pull from the grid and they either won't allow you to put your excess in or won't pay for it if you do.

You may get a decent return, but you're taking on what seems to be significant risk as well. It's certainly less risky if you don't think that you'll move for 20 years or longer and/or you go completely off-grid, which is much more financially viable today than it was a few years ago.
“It's a dangerous business, Frodo, going out your door. You step onto the road, and if you don't keep your feet, there's no knowing where you might be swept off to.” J.R.R. Tolkien,The Lord of the Rings

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Re: Solar with battery/tesla wall

Post by mervinj7 » Mon Jun 29, 2020 3:44 pm

willthrill81 wrote:
Mon Jun 29, 2020 3:22 pm
Wannaretireearly wrote:
Sat Jun 27, 2020 6:04 pm
We have a new roof.. were in NorCal CA.
I dont have an electric car yet.. likely will in the next 5 years.
I dont think I want solar without some kind of house battery/tesla wall to store energy. My monthly Pg&e bill is around 200, mostly electric.
If you're not even paying $200/month for regular electric use (i.e. your home isn't already super efficient), my own research from all of this a year or two ago would strongly suggest that you would be looking at a break-even point at least 20 years out unless (1) get a screaming deal on all of the equipment, not just the panels, and/or (2) you are capable and it is legally permissible for you to do nearly all of the work yourself except for the final connections and inspection.
OP is in California. It's highly unlikely his breakeven point is greater than 20 years like yours is. We live pretty close and our system is on schedule for a breakeven of less than five years. With the new Tesla pricing, the breakeven can be less than 4 years for many folks (assuming one trusts Tesla to follow through). Check out my detailed post on my own install.

viewtopic.php?t=291738

As far as your concern with regulations changing are concerned, in CA net metering is guaranteed for 20 years from the date of original install. So anybody installing right now will be subject to the NEM 2.0 rules for 20 years no matter what happens with NEM 3.0.

https://www.solarreviews.com/blog/calif ... ring-nem-2

What's clear here is that the merits of solar will vary widely across the country and that it's very important to understand ones local regulatory environment.

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willthrill81
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Re: Solar with battery/tesla wall

Post by willthrill81 » Mon Jun 29, 2020 3:49 pm

mervinj7 wrote:
Mon Jun 29, 2020 3:44 pm
willthrill81 wrote:
Mon Jun 29, 2020 3:22 pm
Wannaretireearly wrote:
Sat Jun 27, 2020 6:04 pm
We have a new roof.. were in NorCal CA.
I dont have an electric car yet.. likely will in the next 5 years.
I dont think I want solar without some kind of house battery/tesla wall to store energy. My monthly Pg&e bill is around 200, mostly electric.
If you're not even paying $200/month for regular electric use (i.e. your home isn't already super efficient), my own research from all of this a year or two ago would strongly suggest that you would be looking at a break-even point at least 20 years out unless (1) get a screaming deal on all of the equipment, not just the panels, and/or (2) you are capable and it is legally permissible for you to do nearly all of the work yourself except for the final connections and inspection.
OP is in California. It's highly unlikely his breakeven point is greater than 20 years like yours is. We live pretty close and our system is on schedule for a breakeven of less than five years. With the new Tesla pricing, the breakeven can be less than 4 years for many folks (assuming one trusts Tesla to follow through). Check out my detailed post on my own install.

viewtopic.php?t=291738

As far as your concern with regulations changing are concerned, in CA net metering is guaranteed for 20 years from the date of original install. So anybody installing right now will be subject to the NEM 2.0 rules for 20 years no matter what happens with NEM 3.0.

https://www.solarreviews.com/blog/calif ... ring-nem-2

What's clear here is that the merits of solar will vary widely across the country and that it's very important to understand ones local regulatory environment.
Thanks for the info. You're right that this is incredibly location specific.

I didn't think that under $200/month meant that the OP was paying nearly enough for grid power to make solar worthwhile.
“It's a dangerous business, Frodo, going out your door. You step onto the road, and if you don't keep your feet, there's no knowing where you might be swept off to.” J.R.R. Tolkien,The Lord of the Rings

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TomatoTomahto
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Re: Solar with battery/tesla wall

Post by TomatoTomahto » Mon Jun 29, 2020 4:13 pm

willthrill81 wrote:
Mon Jun 29, 2020 3:49 pm
mervinj7 wrote:
Mon Jun 29, 2020 3:44 pm
willthrill81 wrote:
Mon Jun 29, 2020 3:22 pm
Wannaretireearly wrote:
Sat Jun 27, 2020 6:04 pm
We have a new roof.. were in NorCal CA.
I dont have an electric car yet.. likely will in the next 5 years.
I dont think I want solar without some kind of house battery/tesla wall to store energy. My monthly Pg&e bill is around 200, mostly electric.
If you're not even paying $200/month for regular electric use (i.e. your home isn't already super efficient), my own research from all of this a year or two ago would strongly suggest that you would be looking at a break-even point at least 20 years out unless (1) get a screaming deal on all of the equipment, not just the panels, and/or (2) you are capable and it is legally permissible for you to do nearly all of the work yourself except for the final connections and inspection.
OP is in California. It's highly unlikely his breakeven point is greater than 20 years like yours is. We live pretty close and our system is on schedule for a breakeven of less than five years. With the new Tesla pricing, the breakeven can be less than 4 years for many folks (assuming one trusts Tesla to follow through). Check out my detailed post on my own install.

viewtopic.php?t=291738

As far as your concern with regulations changing are concerned, in CA net metering is guaranteed for 20 years from the date of original install. So anybody installing right now will be subject to the NEM 2.0 rules for 20 years no matter what happens with NEM 3.0.

https://www.solarreviews.com/blog/calif ... ring-nem-2

What's clear here is that the merits of solar will vary widely across the country and that it's very important to understand ones local regulatory environment.
Thanks for the info. You're right that this is incredibly location specific.

I didn't think that under $200/month meant that the OP was paying nearly enough for grid power to make solar worthwhile.
There has to be some value placed on being grid impervious. I don’t know what that amount is, but it is more than $0. We are in the Northeast, and usually have a few multi hour outages annually, with the occasional one lasting more than 24 hours (my personal worst was 8 days after superstorm sandy). Just today, thunderstorms knocked power out for many of our neighbors.
Okay, I get it; I won't be political or controversial. The Earth is flat.

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willthrill81
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Re: Solar with battery/tesla wall

Post by willthrill81 » Mon Jun 29, 2020 4:17 pm

TomatoTomahto wrote:
Mon Jun 29, 2020 4:13 pm
willthrill81 wrote:
Mon Jun 29, 2020 3:49 pm
mervinj7 wrote:
Mon Jun 29, 2020 3:44 pm
willthrill81 wrote:
Mon Jun 29, 2020 3:22 pm
Wannaretireearly wrote:
Sat Jun 27, 2020 6:04 pm
We have a new roof.. were in NorCal CA.
I dont have an electric car yet.. likely will in the next 5 years.
I dont think I want solar without some kind of house battery/tesla wall to store energy. My monthly Pg&e bill is around 200, mostly electric.
If you're not even paying $200/month for regular electric use (i.e. your home isn't already super efficient), my own research from all of this a year or two ago would strongly suggest that you would be looking at a break-even point at least 20 years out unless (1) get a screaming deal on all of the equipment, not just the panels, and/or (2) you are capable and it is legally permissible for you to do nearly all of the work yourself except for the final connections and inspection.
OP is in California. It's highly unlikely his breakeven point is greater than 20 years like yours is. We live pretty close and our system is on schedule for a breakeven of less than five years. With the new Tesla pricing, the breakeven can be less than 4 years for many folks (assuming one trusts Tesla to follow through). Check out my detailed post on my own install.

viewtopic.php?t=291738

As far as your concern with regulations changing are concerned, in CA net metering is guaranteed for 20 years from the date of original install. So anybody installing right now will be subject to the NEM 2.0 rules for 20 years no matter what happens with NEM 3.0.

https://www.solarreviews.com/blog/calif ... ring-nem-2

What's clear here is that the merits of solar will vary widely across the country and that it's very important to understand ones local regulatory environment.
Thanks for the info. You're right that this is incredibly location specific.

I didn't think that under $200/month meant that the OP was paying nearly enough for grid power to make solar worthwhile.
There has to be some value placed on being grid impervious. I don’t know what that amount is, but it is more than $0. We are in the Northeast, and usually have a few multi hour outages annually, with the occasional one lasting more than 24 hours (my personal worst was 8 days after superstorm sandy). Just today, thunderstorms knocked power out for many of our neighbors.
Certainly so. We don't have a solar setup, but we have a portable generator capable of easily and pretty quietly running all of our necessary items and enough fuel on hand at all times to do so for weeks at least. And we can take that generator anywhere we want, including another house, which you cannot do with a solar setup, and our cost was a small fraction of solar. And the generator works at night too.

Solar is clearly a winning financial move when you're paying $.25/kWh or more as many do in SoCal and Hawaii, where they also get abundant sunshine. When you're paying $.08/kWh like we are and don't get much sunshine for a good two months every winter, it's a much longer and riskier play.
“It's a dangerous business, Frodo, going out your door. You step onto the road, and if you don't keep your feet, there's no knowing where you might be swept off to.” J.R.R. Tolkien,The Lord of the Rings

MedSaver
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Re: Solar with battery/tesla wall

Post by MedSaver » Mon Jun 29, 2020 4:23 pm

I’m in NorCal. We only get credits for surplus energy and never get money back. Also, we have to pay $20/month for the privilege of connecting to the grid regardless of surplus produced.

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willthrill81
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Re: Solar with battery/tesla wall

Post by willthrill81 » Mon Jun 29, 2020 4:43 pm

MedSaver wrote:
Mon Jun 29, 2020 4:23 pm
I’m in NorCal. We only get credits for surplus energy and never get money back. Also, we have to pay $20/month for the privilege of connecting to the grid regardless of surplus produced.
Your point that not all areas within even a single state have similar regulations, rates, etc. when it comes to solar setups is very apt.
“It's a dangerous business, Frodo, going out your door. You step onto the road, and if you don't keep your feet, there's no knowing where you might be swept off to.” J.R.R. Tolkien,The Lord of the Rings

harikaried
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Re: Solar with battery/tesla wall

Post by harikaried » Wed Jul 01, 2020 2:01 pm

Starfish wrote:
Mon Jun 29, 2020 2:46 am
Does Tesla price include installing?
Yes. Here's an itemized breakdown of a "Large" 36 panel quote:

Code: Select all

 $6,580    12.24 kW DC Solar Panels
 $3,290    Inverter(s) & Balance of System
 $1,175    Mounting Hardware
$12,455    Installation, Permitting, and Other Fees
-------
$23,500    Total
How Tesla gets bulk panels at $0.54/W ($183/panel)…

mervinj7
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Re: Solar with battery/tesla wall

Post by mervinj7 » Wed Jul 01, 2020 2:54 pm

harikaried wrote:
Wed Jul 01, 2020 2:01 pm
Starfish wrote:
Mon Jun 29, 2020 2:46 am
Does Tesla price include installing?
Yes. Here's an itemized breakdown of a "Large" 36 panel quote:

Code: Select all

 $6,580    12.24 kW DC Solar Panels
 $3,290    Inverter(s) & Balance of System
 $1,175    Mounting Hardware
$12,455    Installation, Permitting, and Other Fees
-------
$23,500    Total
How Tesla gets bulk panels at $0.54/W ($183/panel)…
For those who are wondering what solar panels they use in this quote, it's most likely these. The panels come with 25 year warranties, so I have no clue how their pricing works unless their plan is to take local competitors out of business.

Q.Peak Duo BLK-G6+ / SC 340
https://www.energysage.com/solar-panels ... lk-g6-340/

emoore
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Re: Solar with battery/tesla wall

Post by emoore » Wed Jul 01, 2020 2:56 pm

Thegame14 wrote:
Sat Jun 27, 2020 6:32 pm
going to pay likely double for "tesla" brand. Use energy sage to get quotes then call a local company and see if they will match.
Tesla has actually been the cheapest in most cases. They significantly lowered their prices and during my install a few years ago they matched the lowest.

emoore
Posts: 624
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Re: Solar with battery/tesla wall

Post by emoore » Wed Jul 01, 2020 3:01 pm

mervinj7 wrote:
Wed Jul 01, 2020 2:54 pm
harikaried wrote:
Wed Jul 01, 2020 2:01 pm
Starfish wrote:
Mon Jun 29, 2020 2:46 am
Does Tesla price include installing?
Yes. Here's an itemized breakdown of a "Large" 36 panel quote:

Code: Select all

 $6,580    12.24 kW DC Solar Panels
 $3,290    Inverter(s) & Balance of System
 $1,175    Mounting Hardware
$12,455    Installation, Permitting, and Other Fees
-------
$23,500    Total
How Tesla gets bulk panels at $0.54/W ($183/panel)…
For those who are wondering what solar panels they use in this quote, it's most likely these. The panels come with 25 year warranties, so I have no clue how their pricing works unless their plan is to take local competitors out of business.

Q.Peak Duo BLK-G6+ / SC 340
https://www.energysage.com/solar-panels ... lk-g6-340/
Their plan is to significantly increase the amount of solar and powerwalls they install. I think they are breaking even on solar and trying to get the profits from the powerwalls.

batpot
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Re: Solar with battery/tesla wall

Post by batpot » Wed Jul 01, 2020 3:29 pm

we have cheap electricity here, $0.14/kWh.

Tesla's offering had a break even point at greater than 25 years.
:shock:

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