Yes and Yes. It will be your new toy. You’ll constantly be checking your power input and outputs. Plus the weather.
Anyone with Tesla Solar Panels?
- Thread starter SupraSaltyReefer
- Start date
gmdcdvm
Supporting Member
Sounds like it is pretty complicated given your limited roof space. I agree with what has been said. Get the biggest system you can get because it just keeps getting more expensive. For me the battery in your situation would be mainly as a backup option for when/if you lose power. Given how many tanks you have and how much you have invested it would be good to have a battery backup that can run your pumps and heaters if the power goes out. Something reliable that will automatically kick in. Since we had our system installed, we have lost power three times. Each time it was a seamless transition. We would not have known had our friends not texted to see if our power was out.
I'm glad I got mine when I did, loan was 1.25%. Crazy how much has changed.
I'm glad I got mine when I did, loan was 1.25%. Crazy how much has changed.
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Is that bottom portion the south facing part of your roof? I'd think you could add two horizontally mounted panels without relocating vents and still having the ~18" or whatever they need from each edge of the roof.
Multiple batteries definitely don't make much sense other than having a backup system for when the power goes out. I'd probably just consider one since your panels aren't going to charge them much outside of the longest days and you'd likely be using grid charging to charge them if you need to arbitrage for the more expensive hours of the day.
Update after 2 months? I guess you were waiting for the tariffs? Lol
I agree with others- get the most panel watts you can, and get Powerwalls. The PWs are very helpful even with your solar being only 50% or so of your consumption. They give you power backup, which is worth it on it’s own, and they give you the ability to arbitrage power, which will pay for them pretty quickly.
Tesla installs just Powerwalls as far as I know. They didn’t for a while (required a solar purchase), but then they went back to offering them. That was last year, for all I know they could have changed their mind again but it’s worth checking.
Sizing & ROI
Regarding "I know the batteries are not really beneficial at the moment since I won't even be producing enough energy to fill them", the main thing to keep in mind is net metering (now managed via NEM 3.0) without a battery makes assessing production versus usage more complicated.
For example, let's say your system is only a 33% offset. The peak of that offset is going to be during the middle of the day, and highest in sunny months (eg summer). Let's pretend it's a nice sunny day in July, 74°F at 1pm, and you're away from home so not using extra electric or AC or whatever. Your tanks will be using a lot of electric, but let's say your house is generating 3kWh and you're only using 2kWh for that hour.
That extra 1kWh you generate isn't getting banked, it's getting sent back to the grid. With NEM 3.0 that 1kWh you could be getting basically nothing for that, let's say $0.04 per kWh. Later at 6pm you're generating 0.5kWh and using 2kWh at home. That extra 1.5kWh you need for 6-7pm may cost you $1. Even if for that entire day you generated more power than you used overall, you would owe money for that day.
Earlier versions of net metering weren't this way, or at least this extreme. If it would cost you $0.30 for some electric, if you pushed the same amount of electric to the grid you'd make $0.30. Cost = Payment. NEM 3.0 changed it so what they pay you is almost $0, while they'd continue charging crazy PGE rates.
All the above numbers are made up, but they're not that crazy off. The gist is with NEM 3.0 you need to be careful with the sizing or just get battery backups. The solar people should be able to explain that, but of course they're biased to say you need a ginormous system.
Design
If you're running into issues getting good panel fit on your roof, I would recommend getting another quote from another vendor. In my experience Tesla is not flexible with that, and the other little guys will be hungry for your business and will try more options. The other guys may not be cost competitive in the end, but it can be useful to get a comparison.
Hopefully it's obvious it's shady to get another quote from someone just to get a design to take back to Tesla, but if you can get a better design it might be worth paying a bit more for a different vendor. Over a long time horizon, the initial incremental cost disappears.
Financing
Adding this from just re-reading your messages. Sucks interest rates have shot up, but I wonder if there's other options to get that number down from 7%. Eg can you take a home equity loan out instead? I'm not sure the rates these days.
Though as a positive, as the economy crashes and inflation shoots up to ever increasing crazy numbers, it doesn't matter how much you spend now! $1 of debt in today's money will be meaningless in a year's money when an egg costs $100 a dozen~
Bigfish
Supporting Member
I would say look at Enphase they have a much longer warranty and way better customer service unless you want to deal with a AI assistant (with Tesla) if something goes wrong. I just ended up getting solar and although the power wall is nice they only have a 10 year warranty my Enphase batteries have 15 that extra 5 years to me was worth it. Especially because solar is the ONLY thing they do unlike Tesla that has their hands in many pies so to speak.
The company I went too originally only did roofs they gave me like a 25-30 year warranty on their craftsmanship. (a lot of people have problems dealing with bad installations)
The company I went too originally only did roofs they gave me like a 25-30 year warranty on their craftsmanship. (a lot of people have problems dealing with bad installations)
Alexander1312
Supporting Member
Great that there are alternatives.
I ended up with a hybrid system, Enphase microinverters, but had to go with the Tesla battery due to how much space the Enphase batteries take on the walls (they're something like 5kWh each and I don't have an attached garage). Both systems have pluses and minuses.
Agreed that you should go with a company that isn't a fly by night installer because these systems will need maintenance and support. I've had friends get screwed when trying to sell their houses due to the liens from their defunct installers who's loans were transferred to new debt holders. Or if the installer damages your roof due to a bad install.
MolaMola
Supporting Member
Piggybacking, somewhat related. I would REALLY appreciate if someone could give a sentence explaining how exactly one physically charges an EV with a solar system (includes PW3s).
I THOUGHT we would finally be done yesterday (except for PTO) with our install that started with new roof last spring/summer. Nope. Big rooftop system with two PW3. Everything done, then final city inspection. Out of the blue, city inspector says PW3s are too close together and must be moved. City had approved the plan! He says he knows they approved, but will not sign off. ??? Suggests we request a variance from fire dept bc nat'l reqmts differ from that of the city (which had approved it).
So, installer is going Monday to inquire about the variance. Meanwhile, my husband wondered yesterday that if we must make an alternate arrangement, should we move one PW to the other side of the house where the driveway is? We think it doesn't matter where component units vs extensions are located, but does it?
I THOUGHT we would finally be done yesterday (except for PTO) with our install that started with new roof last spring/summer. Nope. Big rooftop system with two PW3. Everything done, then final city inspection. Out of the blue, city inspector says PW3s are too close together and must be moved. City had approved the plan! He says he knows they approved, but will not sign off. ??? Suggests we request a variance from fire dept bc nat'l reqmts differ from that of the city (which had approved it).
So, installer is going Monday to inquire about the variance. Meanwhile, my husband wondered yesterday that if we must make an alternate arrangement, should we move one PW to the other side of the house where the driveway is? We think it doesn't matter where component units vs extensions are located, but does it?
I’m not sure if I understand your question. But I think I do. Two part question. 1.) solar power is dc current . Ev is dc current. It’s best to charge your Ev when it’s sunny. Dc to dc charging. It’s more efficient. You skip the ac converter which takes up power.
2.) moving the power wall across the house. There is a voltage drop in the cable but nothing major. So do the math on which one is going to cost you more. Move the power wall or run a thick power cable. There’s a math equation for it but I don’t remember it.
I hope I understood correctly. If not I’m sorry.
How one charges an EV with a solar system/PWs: You don’t, directly. Everything connects in to your home electricity system and functions more or less independently. The solar generates electricity. The Powerwalls store electricity and release it on demand. The EVs use electricity when you set them to. Could go into each part in much more detail, but you asked for the simple version
When people say something is charging their car, it is mental accounting, or the electronic version of that on the app. The exception to this is if you go off-grid.Regarding the rules about where to place Powerwalls, it is a complete cluster****. There are city rules, county rules, state rules, fire dept rules, and whatever the specific inspector thinks on a given Tuesday. But basically, you can’t have them too close to one another or too close to a window. When I had my first set installed, I was one of the first residential customers and they didn’t have all these rules. I put them where I wanted them in my garage. When I added the second set more recently, we went around and around with it and eventually found a place that seemed to satisfy the rules, not at all where I wanted them.
Ugh that's so annoying. City of Oakland did the same with my parents' install where the different inspectors delayed the project because they wanted different things (signage, had to put the battery super far away on the other side of the house to give enough space from windows, etc.) make sure they have an accurate site plan placard after finishing. I've gotten delayed on my install because of this for weeks.
They put the car charger about 10 feet away from the battery on the driveway (most of the electrical panels and inverters are on the opposite side of the house and away from any gas lines etc.) and my dad generally charges either after the house battery is charged during a big surplus day, or super late at night. T they're also NEM 2.0 so they can get away with selling back surplus pretty well. You'll need to figure out what PG&E plan to go with once you're grid connected depending on your actual production and use.
Enphase released a charger recently that only charges with your excess solar. It only works with enphase systems iirc I put one in on my house 2 weeks ago. It seems to work ok but it’s been cloudy when I’ve been home to really test it out.
I highly recommend Kingdom Solar after a ton of shopping around and Tesla randomly canceling my contract. They were about 30% cheaper than any other quote I got (other than Tesla). I only found them by pulling over to a neighbor’s house who was getting solar installed and chatting with the crew. Almost everyone online seemed to be a middle man that just does referral leads.
See pic below. The orange highlighted area around 1pm is the car taking the extra solar
I highly recommend Kingdom Solar after a ton of shopping around and Tesla randomly canceling my contract. They were about 30% cheaper than any other quote I got (other than Tesla). I only found them by pulling over to a neighbor’s house who was getting solar installed and chatting with the crew. Almost everyone online seemed to be a middle man that just does referral leads.
See pic below. The orange highlighted area around 1pm is the car taking the extra solar
Details of your electric plan matter, and PGE is always changing available plans, but for me and probably most people letting your excess solar go back to grid gives you peak or off-peak full retail value credit for it, and then you can charge your car for cheaper at night. Much more cost effective, basically you are “paying” twice as much per kWh for your car to do it the above way vs what I described.
I believe you're saying that in the mindset of someone under NEM 2.0 or NEM 1.0. As of NEM 3.0, you never get "full retail credit value".
My understanding is the buybacks are averaging around $0.05, and there literally are times of day/year where they pay back $0.
The arbitrage people do under NEM 1&2 don't apply to 3.0. That's why the solar industry in California is crashing, because the economics are much more difficult to work out, and require a big initial investment because you need batteries. In NEM 3.0's defense, that's exactly what their goal was (force people that can afford solar to pay more and also to force batteries). I don't agree that's a good goal, but at least it's coherent.
Disclaimer that I have researched this a bunch of times, but I snuck in on 2.0 at the last moment, so I don't want to come across as a fully accurate source.
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You’re probably right. I haven’t looked carefully recently and I’ve had my panels, batteries, and EVs for a long time so I’m probably just grandfathered-in to a better deal I guess.