Advice needed - Still in planning stage

[solson223]

SCE (Edison) sent a few people out last week to confirm that I could upgrade to 200A service. I talked to them, asked questions, and they confirmed on the spot (and follow-up phone call) that I was okay to install and 200A service panel. I already have an active permit. However, I remember the electrician saying I had 1/0 service wiring to the house, so I'm good to go. I didn't research it at the time, and I have now, and I've read that I'd need minimum 2/0 copper to put in a 200A breaker. Either I heard him wrong or I got bad info. I'm going to follow up with them again after the weekend to have them clarify. I currently have 100A service panel.

Regardless of that, if I do have 1/0 wiring to the house, I should still be capable of 150A from what I've read. I plan to to still upgrade to a 200A panel (225 bus) and put in a 150A main breaker if the original wiring info of 1/0 I got was correct.

My plan is for an 8kW system, grid-tied, Sol Ark 15K inverter, 20x 400W Q Cell panels, and 30kWh (6x LifeForce4 100 AH batteries with hub) battery backup.

Would I be making the right move in going with a 200A panel with 150A breaker to give myself enough (120% rule) backfeed potential? Maybe it's not necessary with an 8kW system? Should I be looking at the Sol Ark 12K or maybe the EG4 18K instead of the Sol Ark 15K?

Just looking to verify some things before I have my plans drawn up and submit to the city and Edison. And definitely before I buy anything.

Thanks.

 

[cdherman]

So your Sol Ark 15k and EG4 18k both as hybrids are best utilized between your meter and your loads, if you want them to function as a backup power system (which is the attractive aspect), and the reason to have batteries, usually, if you are net metering.

If you are going to use an AIO as grid tie only, and hook them up to your main load center as a feeder, then they CANNOT provide backup power easily or instantly. Or safely for that matter. And if you are going grid tie, there are myriad cheaper options, and you don't need the batteries. You may very well need to upgrade your panel for a grid tie system, simply since you are out of spaces.

You do not seem like someone who is interested in the "peak shaving" aspect, where you use your batteries in conjunction with an AIO to use TOU (Time of Use) rate plans to reduce your bill.

Your questions about your 200A service are correct though. Yes, you can very much use a 225A service panel, but derate to 150A based on the lines from the pole. However, you *may* not need to. The service entrance wires can be over rated in the other direction at times. I cannot explain this well, as its just not my area of expertise. Hopefully someone else will happen along to help.

Also, ALu versus copper needs to be mentioned when discussing large lines. I assume your 1/0 is Alu -- but an older house might have copper I suppose.....

 

[DIYrich]

1/0 wire might be the difference between in air (chassis) vs conduit.

 

[goldserve]

First you need to measure the diameter of the cable using calipers and correlate with thhnw dimensions online. Also find out if you have copper or aluminum because that makes a huge difference. For service entrance wire rating, it’s not the same table as wire ampacity ratings. I recently did my own OH service upgrade to 200A and used 2/0 copper. If you really have 1/0 copper wires, you are in-between 150 and 200A so I guess you can use a 175A main breaker and have 240A-175A = 65A rounded to 60A solar back feed breaker on a 200A bus bar panel.

 

[solson223]

Edison texted me back today and told me that I have 1/O Aluminum - via the inspection they did. So that means I'm rated for a max of 125A main breaker from what I've read. I have no idea why they told me (twice) that I was good to go for upgrading to a 200A service. I texted back with that question but no reply, yet.

So with that said, my plan is to upgrade to a 200A panel (225A bus) anyway and put a 125A main breaker in. Since the 120% rule is based off of the bus bar rating, and essentially I'd have have 270-125 head room, putting a 60A PV breaker in should be no problem, right? I think the Sol Ark 15K can only output 62.5A max anyway. Do I have this all wrong or am I on the right path? I'd rather be completely wrong now before I buy anything.

Thanks.

 

[DIYrich]

How about keeping your existing panel, and feed the Sol-Ark Grid Input from there.
New 200 amp panel goes on the Load side of the Sol-Ark.
Set the "Grid Support" feature of the Sol-Ark to just under 30,000 watts (125 amps x 240v). Anything over 30,000 watts would be supported by the Sol-Ark.
Max feedback to grid would be 15kW, so no problem there.

If you feed the new 200amp panel with both grid and sol-ark, then you need an isolation swtich to island when the grid goes down.

 

[solson223]

How about keeping your existing panel, and feed the Sol-Ark Grid Input from there.
New 200 amp panel goes on the Load side of the Sol-Ark.
Set the "Grid Support" feature of the Sol-Ark to just under 30,000 watts (125 amps x 240v). Anything over 30,000 watts would be supported by the Sol-Ark.
Max feedback to grid would be 15kW, so no problem there.

If you feed the new 200amp panel with both grid and sol-ark, then you need an isolation swtich to island when the grid goes down.

Thanks for the reply. The panel replacement is a must. The slots are full and the metal is rusting all over. I can't even read anything that was previously marked in there. The box is probably original (late 70's). The panel is for sure getting replaced no matter what.

I'm still a newbie to the Solar aspect of this. So the grid feeds the Sol Ark as a pass through, the Sol Ark then feeds the panel? Is the panel then treated as a sub panel? No bonding of the ground and neutrals?

 

[DIYrich]

Don't know about the ground/neutral issue.

I suggest installing the Grid to a bus bar (or splitter), with one line to a Disconnect Switch (or breaker) that feeds the Sol-Ark.
The second line goes to one input of a Manual Transfer Switch.

The Load output of the Sol-Ark goes to the other input of the Manual Transfer Switch.

The output of the Manual Transfer Switch goes to your new 200 amp load panel.

That way, if you need to take the Sol-Ark off-line, you Switch the Manual Transfer Switch to the Grid Input, and flip the Disconnect Switch to remove power to the Sol-Ark. Also helpful when you need to reboot the sol-ark. Switch the Manual Transfer Switch to the Grid, and update/reboot the Sol-Ark, then flip the Manual Transfer Switch back to the Sol-Ark.

 

[goldserve]

The ground to neutral bonding happens at the first means of disconnect. Does the meter have a breaker before the solark? If so, the bonding happens there. In any case, you should have a means of disconnect so you can take down the solark for service, replacement without the need to pull the meter which is illegal in most jurisdictions.