Best Options for UL9540 inverter and battery on small 2.2kW system

[Ochobeeguy]

I'd like to put up just 6 panels on the garage to provide 2.2kW. I just want an off-grid system to power a fridge and freezer, or occasional tools or use as an emergency backup if power goes out. My first idea was to connect them directly to the Bluetti AC300 and a couple of batteries. This was shot down by the city (Herriman Utah) because they insist on it being UL9540 compliant. I'd love to see if anyone knows which inverter/battery combinations will pass this. I don't think there are very many. I've seen SolArk 5k + Fortress eflex but that comes in at $15000. I was excited when I heard about EG4 and being UL listed since the cost of that would come it at less than $4500. Are there any systems that can beat out the SolArk and Fortress in cost? Or any battery options for less than the Fortress? Hoping for about 8-10KwH.

 

[cs1234]

Unfortunately I have no advice to offer as UL9540 is very recent and it seems anything compliant with it is outrageously expensive unless you are willing to start with some lead acid batteries and cheat by replacing them later. Keep in mind they are going to require every single item used in the install to also be UL compliant/listed (surprised if only compliant).

Your story is a sad one, but one I will watch with great interest.

 

[damo green]

Unfortunately I have no advice to offer as UL9540 is very recent and it seems anything compliant with it is outrageously expensive unless you are willing to start with some lead acid batteries and cheat by replacing them later. Keep in mind they are going to require every single item used in the install to also be UL compliant/listed (surprised if only compliant).

Your story is a sad one, but one I will watch with great interest.

Some people keep mentioning that Lead Acid batteries are not part of NEC 2020 and UL9540 , but it doesn't read that way to me... It think ALL ESS systems have to meet it no matter the chemistry.... ("Article 480 Storage Batteries" may not have to be but ESS's Article 706 Energy Storage Systems, do )......? I think for PV systems you have to follow 706 not 480

 

[cs1234]

Some people keep mentioning that Lead Acid batteries are not part of NEC 2020 and UL9540 , but it doesn't read that way to me... It think ALL ESS systems have to meet it no matter the chemistry.... ("Article 480 Storage Batteries" may not have to be but ESS's Article 706 Energy Storage Systems, do )......? I think for PV systems you have to follow 706 not 480

You could be right, the whole section is a pile of crap that should be thrown burning back at their doorstep.

 

[damo green]

was doing some more digging tonight: (2018 vs 2020 code) this is why people keep repeating Lead Acid as being except from UL listing, I guess.

NEC CODE 2018: " (2018 NEC) 706.5 Equipment. Monitors, controls, switches, fuses, circuit breakers, power conversion systems, inverters and transformers, energy storage components, and other components of the energy storage system other than lead-acid batteries, shall be listed. Alternatively, self-contained ESS shall be listed as a complete energy storage system."

Vs 2020 NEC "706.5 Listing Energy storage systems shall be listed"

 

[westcoastfox]

I was looking at adding a ESS, non-grid-interactive system at my house, without the $$$$.

I found Pytes E-BOX-48100R LiFePO4 server rack battery is UL listed. Available on Watts247, for ~$2000.
They got the UL9540 listing with sol-ark, per https://www.pytesgroup.com/news-detail/&5380

But since Sol-ark is very expensive, i tried to determine whether I could use a different UL 1741 listed inverter, e.g. Growatt has some.

But it looks like answer is no, a UL 9540 ESS is certified as specific pairs of battery+inverters.

Which sucks for manufacturers that only does battery or inverters, you have to partner with several other manufacturers.
And sucks for consumers as there are mostly just expensive combinations available, and requirements of UL listing on top of UL listing means we either wait or pay $$$$.

 

[damo green]

I was looking at adding a ESS, non-grid-interactive system at my house, without the $$$$.

I found Pytes E-BOX-48100R LiFePO4 server rack battery is UL listed. Available on Watts247, for ~$2000.
They got the UL9540 listing with sol-ark, per https://www.pytesgroup.com/news-detail/&5380

But since Sol-ark is very expensive, i tried to determine whether I could use a different UL 1741 listed inverter, e.g. Growatt has some.

But it looks like answer is no, a UL 9540 ESS is certified as specific pairs of battery+inverters.

Which sucks for manufacturers that only does battery or inverters, you have to partner with several other manufacturers.
And sucks for consumers as there are mostly just expensive combinations available, and requirements of UL listing on top of UL listing means we either wait or pay $$$$.

yep, a lot of the youtube solar presenters fail to even briefly mention the code side of things. they say "for off grid" ...but most non grid connected systems need to meet code requirements like you mention.

 

[solar_trees]

Are batteries under 1KWh exempt from the UL listing requirement? My state follows NEC 2020 and mentions this in its residential codes. I'm also planning to do a small system and the only way this is going to be possible for me is if smaller batteries are exempt.