Any advice on this solar proposal I’m about to pull the trigger on?

[TapHabit]

Hey guys, so i just received my latest proposal from Tesla for an array I’m planning on getting installed within the next month. We went back and forth on a few designs, as one of the things i’m spec Trying to do is hedge some of my power usage in my shop which runs both kilns and small AC units overnight. As well as charge my S85D. The solar array seems robust, and I’m quite happy with it. The engineers seemed to have no trouble getting power to the 100amp breaker which powers the shop, and the ditch they’ll need to dig is included in this breakdown. Anyway, this whole thing is relatively new to me (few months of light research) and I’m wondering if anything about this proposal or usage stands out to anyone or if anyone has any advice on something i may not be seeing. The only potential change i may make is beefing it up to 4 PW’s, but as is with 3, i’ve Been informed we can do a whole house backup which is great if you live in CA and PG&E now will just shut your power off on windy nights. (Screw PG&E, really). I’d obviously make some adjustments to my usages if installed, but i’m Wondering if anything stands out to anyone as far as me missing something. My current power bills are around $1100, this proposal would cost me $490 to Tesla, although i’d own the system. My main goal is to pay pg&e the least amount of money possible monthly, as well as be somewhat self sufficient in my power and travel usage. Thanks in advance everyone!

 

[Pale_Rider]

FYI, that size system will not totally replace your electric bill... I’ve got a 23kW system already and will be having 3 powerwalls installed next week. Granted I’m on the coast of Texas so I probably have a few more cloudy days and get hotter (which also impacts performance) and my panels are split up about 1/3 east, 1/3 west and slightly less than a third to the south. The highest single day output I’ve had was back in March of right under 140 kWh. So far the last few months it’s been unusually cloud so I’ve not had a totally clear day during any of the “longest” days of the year. I’m sure I’d go a little over 140 kWh but the panels start to get temp limited it seems. If it’s sunny and hot (mid-90’s) the panels are over 170 degrees and I can see the performance flat line below where it would be on a cooler day.

Just something to keep in mind. Depending on how your panels are laid out you might get more or less, but you won’t get anywhere near 200 kWh per day. I know someone with a 27kw system and the max they have ever seen is about 156 kWh. So I hope you aren’t expecting this system to completely replace your power bill.

Also for us, luckily we have dollar or dollar net metering and no time of use pricing, but the 3 powerwalls would get us completely off the grid in the winter but 3 are about 20 kWh too small to carry us through the night in the summer. We use around 100 kWh total per day during the summer. Hope that helps.

 

[TapHabit]

FYI, that size system will not totally replace your electric bill... I’ve got a 23kW system already and will be having 3 powerwalls installed next week. Granted I’m on the coast of Texas so I probably have a few more cloudy days and get hotter (which also impacts performance) and my panels are split up about 1/3 east, 1/3 west and slightly less than a third to the south. The highest single day output I’ve had was back in March of right under 140 kWh. So far the last few months it’s been unusually cloud so I’ve not had a totally clear day during any of the “longest” days of the year. I’m sure I’d go a little over 140 kWh but the panels start to get temp limited it seems. If it’s sunny and hot (mid-90’s) the panels are over 170 degrees and I can see the performance flat line below where it would be on a cooler day.

Just something to keep in mind. Depending on how your panels are laid out you might get more or less, but you won’t get anywhere near 200 kWh per day. I know someone with a 27kw system and the max they have ever seen is about 156 kWh. So I hope you aren’t expecting this system to completely replace your power bill.

Also for us, luckily we have dollar or dollar net metering and no time of use pricing, but the 3 powerwalls would get us completely off the grid in the winter but 3 are about 20 kWh too small to carry us through the night in the summer. We use around 100 kWh total per day during the summer. Hope that helps.

No I’m not hoping to fully replace my max usage, my goal is to give the least amount of money possible to pg&e. In the very least, combine the $490 I’d be paying Tesla monthly, combined with what I use from pg&e, and have that number be less than the $1200 I’m paying currently.

In an outage, I could easily power down nearly half of my current usage which is mostly on kilns, and AC units that could easily not be used in that situation.