Powerwall 3 vs EG4 18k to run my shop

installing around 8k of panels on my shop to power lights, tools, outlets, a 12k btu mini split, and a level 2 EV charger. I've been pricing an EG4 18k system but I can't find anyone to install it. Our county permitting department is very anti solar and anti DIY. They won't even talk to me about permitting until I had an engineer draw up plans.

I'm getting quotes for a single Powerwall 3 with 8k of panels around $27k before incentives for a turnkey install compared to around $15k for the EG4 system.

Anybody else considering a Powerwall 3?

I was hoping to get the panels professionally installed and then do the EG4 setup DIY but I'm not having any luck finding an installer willing to just do the panels.

Ask what the cost for a second powerwall3 is:

The PowerPro Battery is $3799, 10% more juice than the powerwall3 and you can install it yourself with 2 DC quiclk-connect cables

14kwh is rarely enough for anyone

where are you located?

Can you get the 8k of panels installed with a cheap grid $600 grid tie inverter and add the battery system later?

I'm in Eastern NC, specifically Pitt county. We are sort of a solar black hole county due to an unfriendly permitting debt and terrible net metering rules.

A single Powerwall 3 is $8400 and you can get $500 off with a refferal code. You get $1100 off each power wall when you buy more than one.

Yes, I could get a cheap grid tie inverter but again, terrbile net metering policies (higher base rates, demand charges, and less than wholesale payments) make it pretty dumb. Really aiming for a Zero export or self consumption system.

A single Powerwall would likely run everything just fine. Honestly, I'm hoping my next EV is bidirectional so that would be my battery storage.

watchdoc said:

I'm in Eastern NC, specifically Pitt county. We are sort of a solar black hole county due to an unfriendly permitting debt and terrible net metering rules.

A single Powerwall 3 is $8400 and you can get $500 off with a refferal code. You get $1100 off each power wall when you buy more than one.

Yes, I could get a cheap grid tie inverter but again, terrbile net metering policies (higher base rates, demand charges, and less than wholesale payments) make it pretty dumb. Really aiming for a Zero export or self consumption system.

A single Powerwall would likely run everything just fine. Honestly, I'm hoping my next EV is bidirectional so that would be my battery storage.

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Sounds like your choices are very limited.

SignatureSolarJames said:

Ask what the cost for a second powerwall3 is:

The PowerPro Battery is $3799, 10% more juice than the powerwall3 and you can install it yourself with 2 DC quiclk-connect cables

14kwh is rarely enough for anyone

Click to expand...

I'm already a signature solar customer and I would prefer to stick with the DIY route but I'm unable to install panels on a steep roof and the county permitting dept won't even talk to me without engineering plans. Do you guys offer any guidelines or plans for code compliance?

1201 said:

Sounds like your choices are very limited.

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limited yes, impossible no. I skirted around the county with a small 3kw system by calling it a "portable solar generator" but I won't be able to do that with a larger system attached to the roof of my shop.

1201 said:

Can you get the 8k of panels installed with a cheap grid $600 grid tie inverter and add the battery system later?

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This is likely the cheapest route but where do you find a professional installer that will install just panels with proper permitting? When I ask the local solar companies about doing this, they just flat turn me down.

BTW, I already have a "cheap $600" inverter (Growatt 3000 TL LVM-ES) that I use to charge my Leaf. This would be a much bigger system. Cheap inverters would never get permitted here.

Just take your shop off grid with an 18k and 3 Powerpro batteries, super easy to install.
Have the panels professionally installed if you don't want to do roof work or DIY with a ground mount.
You have a shop, you can do this.

Quattrohead said:

Just take your shop off grid with an 18k and 3 Powerpro batteries, super easy to install.
Have the panels professionally installed if you don't want to do roof work or DIY with a ground mount.
You have a shop, you can do this.

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That's the general idea. "selfish solar" setup. Unfortunately, shading makes a large ground mount system difficult. I would have to trench about 50 yards away and still have to permit everything with the county so the roof mount vs ground mount would likely end up being a wash cost wise when you account for cabling and trenching. The address is 1325 Foster Road in Grimesland, NC 27837 if anyone is curious. I've had several consults from regional solar companies and they agreed. My biggest issue is finding someone that will install the panels alone (with permits).

watchdoc said:

I'm already a signature solar customer and I would prefer to stick with the DIY route but I'm unable to install panels on a steep roof and the county permitting dept won't even talk to me without engineering plans. Do you guys offer any guidelines or plans for code compliance?

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There are services that help with plans and offer wet stamp services ( PE sign off needed for permit applications )
I used greenlancer

watchdoc said:

This is likely the cheapest route but where do you find a professional installer that will install just panels with proper permitting?

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Definitely not an expert here, but I would reach out to several roofing companies and have them install the panels. Most installers up in NE sub it out to roofers if they don't have a roofing company on the side.

harjms said:

Definitely not an expert here, but I would reach out to several roofing companies and have them install the panels. Most installers up in NE sub it out to roofers if they don't have a roofing company on the side.

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So I actually know a bunch of roofers due to my business. Around here, they are either predatory or don't have any experience with solar and are too busy to learn just for me. I would rather pay a professional solar installer to do that part right. That being said, I do have an account with Greentech so I could buy the panels and racking myself and buy the inverter and batteries from SS

watchdoc said:

So I actually know a bunch of roofers due to my business. Around here, they are either predatory or don't have any experience with solar and are too busy to learn just for me. I would rather pay a professional solar installer to do that part right. That being said, I do have an account with Greentech so I could buy the panels and racking myself.

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That's fair...I'd just put a caveat in that not all professional solar installers are professional roofers. There's a lot of solar installers up here in NE that have caused leaks in people's homes due to missing the rafters and/or not sealing the holes.

harjms said:

That's fair...I'd just put a caveat in that not all professional solar installers are professional roofers. There's a lot of solar installers up here in NE that have caused leaks in people's homes due to missing the rafters and/or not sealing the holes.

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agreed, the difference being the professional solar installers almost all give a lifetime warranty on the roof work. (for whatever that's worth)

SignatureSolarJames said:

Ask what the cost for a second powerwall3 is:

The PowerPro Battery is $3799, 10% more juice than the powerwall3 and you can install it yourself with 2 DC quiclk-connect cables

14kwh is rarely enough for anyone

Click to expand...

I have to agree with James on this one.

While I enjoy my Tesla and I’m sure their solar products are nice, I have to imagine the difference in cost is so substantial that it decimates your ROI. Going with Tesla you’ve locked yourself into an expensive ecosystem that you’re effectively unable to work on. In this case I think it makes far more sense to go the EG4 route and expand as needed. Batteries and inverters are certainly trending downwards in cost, so future expansion or replacement should become even better cost wise.

I've considered going the DIY guerilla route but I don't have a good spot where 8k worth of panels wouldnt be very obvious and attract the attention of the local inspectors. They actually have people that drive around and look for code violations around here to A. generate fines and B. increase the tax base for unpermitted structures. To add insult to injury, our county property valuations just came out.... most of our properties DOUBLED in value.

watchdoc said:

I've considered going the DIY guerilla route but I don't have a good spot where 8k worth of panels wouldnt be very obvious and attract the attention of the local inspectors. They actually have people that drive around and look for code violations around here to A. generate fines and B. increase the tax base for unpermitted structures. To add insult to injury, our county property valuations just came out.... most of our properties DOUBLED in value.

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Definitely don't do the un-permitted route. The paperwork and permitting portion was an absolute nightmare for me, it was only at the end when I was pulling my hair out I learned about a company called Vector Engineering. I was struggling with the inspector wanting stamped engineering plans for trusses, a very specific site plan and a few other things that were completely unattainable for a homeowner. I paid $125 for everything I needed through them and it was done in 2 days.

If I were to do it over again, I would have gone with them from the beginning, I think the entire "package" for them to do everything permit wise was about $300, it's a no brainer. I'm not sure if you "have" to be a contractor or not to hire them, fortunately I am and I set up an account, so if they won't let you, let me know and I'd be happy to assist.

That offer goes for everyone on the forum, I'm not asking for a single dollar, I'll do the back and fourth for free. I know the permitting process is/was what has stopped so many of us from moving forward and I can say this place sincerely made it easy. I'm sure there are others out there, I only found out about this company because my inspector informed me 'off the record' that they handled 80% of the solar permits he inspected in our area.

watchdoc said:

A single Powerwall would likely run everything just fine. Honestly, I'm hoping my next EV is bidirectional so that would be my battery storage.

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This is the real point in a powerwall. I also believe Tesla energy and the ability to sell power back at peak usage will more than offset the 8400 cost over time. But its a gamble

Imagine selling 50kwh battery power from your Tesla during peak hours then recharging off peak and making $.10/kwh or $5/day or 150/mo all for doing nothing. Maybe not realistic numbers in coal country like we are but out west and places like TX it'll likely be greater. And who knows what'll happen in 5-10 years and if the EPA shuts down coal plants