Best Sol-Ark 15 Battery?

[zanydroid]

I am not sure how much precision there is intrinsically in these kWh measurements given voltage variation.

And NEC does have whole number rounding rules for many calculations. I’m not sure about IRC.

 

[Brucey]

Then you really need to be careful about UL 9540. No single rack can exceed 20kWh, and 3 ft separation between racks. No more than 40kWh in any one location. Location being: 1) Inside house; 2) Garage; 3) outside house.

A rack battery is typically 5.1kWh, so 4 batteries is 20.4kWh, which exceeds 20kWh. So you are limited to 3 rack batteries per rack.

Unless the inverter and battery(s) have been tested together (9540A), that is the exception to the 20kWh stack rules I believe.

 

[Ampster]

I got my permit approved for 4 Pytes V5 batteries and V-BOX-OC enclosure. NAZ had a special going until Feb 21st. Came in under $8,000 with shipping and Sales tax.

 

[zanydroid]

Unless the inverter and battery(s) have been tested together, that is the exception to the 20kWh stack rules I believe.

I know about the exception for the spacing between stacks but I’m not sure about within a stack.

I wouldn’t be surprised if the per stack rule gets relaxed in a few years after some lobbying

 

[Mr.Hyde]

I currently debating batteries to pair with my upcoming Sol-Ark 15k. As much as I like the Pytes stuff, I'm struggling with the fact that the PowerPro seems to be almost double the energy density (volume, not weight) of the various Pytes enclosures.

 

[Brucey]

I know about the exception for the spacing between stacks but I’m not sure about within a stack.

I wouldn’t be surprised if the per stack rule gets relaxed in a few years after some lobbying

"The significance of the new UL 9540 requirements is as follows: Prior to the changes, there were no requirements in the first edition of UL 9540 that limited the maximum energy capacity of ESS units. For example, it was possible to certify (list) a 200 KWh unit with no UL 9540A fire testing. To approve an indoor installation of this larger ESS unit or an installation with separations less than three feet, the code official would have to ask for the UL 9540A test report, review the detailed findings, then determine if the proposed ESS size and spacing should be approved. This can be a very complicated process for many code authorities.

With the new UL 9540 requirements in place, the process is simplified. ESS larger than 50 KWh or with separations less than three feet cannot be listed to the second edition of UL 9540 without complying with appropriate UL 9540A fire test performance requirements. To determine compliance with a specific installation’s size and separation requirements, code authorities simply have to confirm that the ESS is certified (listed) to the second edition UL 9540, and is installed in accordance with the listing and the manufacturer’s installation instructions, which includes minimum separation distances. The system designer and code authority still need to review the UL 9540A report to evaluate flammable gas release data. The data may be needed to design code-mandated explosion control systems. As can be seen, better aligning the UL 9540 second edition requirements with UL 9540A large-scale fire testing and code requirements will help the system designer and code authority determine code compliance. "

UL 9540 Energy Storage System (ESS) Requirements - Evolving to Meet Industry and Regulatory Needs

In recent years, installation codes and standards have been updated to address modern energy storage applications which often use new energy storage technologies.

www.ul.com

Now that was May 2020. We can only hope it's revised again since then.

So interesting part there about evaluating flammable gas release data. I think there was a thread recently about how much hydrogen gas could be released by a failing LFP cells/battery and it ended up being a very large volume of air needed to keep the gas concentrations at safe levels, even with smaller sized battery. So potentially even a 9540A approved design may still need some type of active ventilation put in place if the local inspector is a stickler.

 

[zanydroid]

Now that was May 2020. We can only hope it's revised again since then.

Third edition came out in mid 2023 so some of that stuff may be out of date already

 

[BlindBadger]

I currently debating batteries to pair with my upcoming Sol-Ark 15k. As much as I like the Pytes stuff, I'm struggling with the fact that the PowerPro seems to be almost double the energy density (volume, not weight) of the various Pytes enclosures.

Only way to go more dense is the little standoffs for stacking the batteries (no enclosure then). There’s also a limit to how many power pros you can connect together for closed comms. If you don’t run into any of that as an issue, the power pros are really cool!

 

[robby]

Third edition came out in mid 2023 so some of that stuff may be out of date already

Yes it has come out and some of the stuff has been relaxed.

 

[robby]

I mean…their enclosures are usually only 3-4 batteries which sort of puts them in that range, no? (Or could be argued potentially)

Personally I would just buy the rack with 4 and if the fourth is causing a fuss I would just remove it until the system has passed inspection. There is a risk involved so it's up to you, but I honestly don't see them getting concerned over 400W of extra power.

 

[Ampster]

PowerPro seems to be almost double the energy density (volume, not weight) of the various Pytes enclosures.

Pytes talked about convection cooling in their enclosures so some of that may be a feature.
Have you compared the volumetric density of a rack module? My decision was based on the communications with the SolArk, the WIFI module monitoring and the battery heater because I have to mount the enclosure outdoors.

 

[SunDave]

Maybe things changed, maybe I was lucky. I passed inspection with a forest RB with 30.72kw of Pytes batteries. I'm sure there are differences in where you live. I can tell you that it was a very meticulous inspection, with almost everything, including wire type, grounding, each unit's rating vs. breakers, etc. It was no quick job.

 

[SilverbackMP]

Ah…now I understand why SMA replaced Sunny Boys with Sunny Energy…they can spread the batteries out easier.

Personally, I don’t want them spread out. I want my highest fire risk contained to one out building. I can see the reasoning in more urban areas though (still makes it an added hindrance).

 

[SunDave]

Personally, I don’t want them spread out. I want my highest fire risk contained to one out building. I can see the reasoning in more urban areas though (still makes it an added hindrance).

I agree. I think a rule to spread them out is short sighted, and doesn't acknowledge that a complex setup with more wiring is more of a risk than the denser pack. Poorly planned mitigation does more harm than good.

 

[DIYrich]

I think a rule to spread them out is short sighted, and doesn't acknowledge that a complex setup with more wiring is more of a risk than the denser pack. Poorly planned mitigation does more harm than good.

Let's say that more wiring increase the risk of having a fire. Lots of electrical fires. Many are localized, and only damage the immediate area.

If you put two racks side-by-side, the risk is that one rack will start the adjacent rack on fire. Remember that NEC code is based upon LI, not LiFePO4. LI is notoriously hard to put out, and you just made it twice as hard. Plus you have twice as much fuel to light the entire house in a fire.

The 3 feet rule is to keep the other rack safe (assuming that it too is UL9540, and has some fire resistance).

 

[SilverbackMP]

Let's say that more wiring increase the risk of having a fire. Lots of electrical fires. Many are localized, and only damage the immediate area.

If you put two racks side-by-side, the risk is that one rack will start the adjacent rack on fire. Remember that NEC code is based upon LI, not LiFePO4. LI is notoriously hard to put out, and you just made it twice as hard. Plus you have twice as much fuel to light the entire house in a fire.

The 3 feet rule is to keep the other rack safe (assuming that it too is UL9540, and has some fire resistance).

You are overlooking this: “No more than 40kWh in any one location. Location being: 1) Inside house; 2) Garage; 3) outside house.”

40KWH is ok for grid tied. It’s ok for off grid should the sun always shine and/or want to live like a pauper. It’s not ok if you want normal amenities and/or have a shop.

 

[DIYrich]

You are overlooking this: “No more than 40kWh in any one location. Location being: 1) Inside house; 2) Garage; 3) outside house.”

40KWH is ok for grid tied. It’s ok for off grid should the sun always shine and/or want to live like a pauper. It’s not ok if you want normal amenities and/or have a shop.

I'd rather have one rack of 15kwh on fire than two racks of 15kwh on fire, or even one rack of 20kwh.

The 3 locations give you the ability to have 120kWh installed at one house, or 92 kWh if you limit yourself to racks of 15kWh. You could literally have them all within 10 feet of each other: 40kWh inside the house at a corner next to the garage, 40kWh outside the house on the other side of the wall from the inside 40kWh, and 40kWh in the garage, on the other side of the wall from inside the house. I'm not saying that is ideal, but not prohibited.

UL also gives you the option to have your specific setup tested that does not meet the UL 9540 safe harbor.

 

[SilverbackMP]

I'd rather have one rack of 15kwh on fire than two racks of 15kwh on fire, or even one rack of 20kwh.

The 3 locations give you the ability to have 120kWh installed at one house, or 92 kWh if you limit yourself to racks of 15kWh

And I’d rather have my 12x12 power shed on fire than my 48x36 finished shop, my moms house, or other outbuildings.

I will have around 135 KWH when I finish my build. Am I supposed to have four different climate controlled power sheds? The NEC go can f&@k itself. Quite literally as I am in Missouri.

 

[Suncahser]

I recently installed a 15k and went with 6x Ruixu batteries. Comms worked right out of the box. Haven't had any issues so far.
The Ruixu rack is very nice, would definitely recommend.

open or closed loop

 

[n1helix]

open or closed loop

Closed