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UL 9540 is the listing required for integrating batteries with the grid such with the connected Solutions program in Massachusetts and the analogous program in CA.fafrd, I could be wrong as I am fairly new to this but I believe many authorities would be looking on the batteries for UL 1973 "ANSI/CAN/UL Standard for Batteries for Use in Stationary, Vehicle Auxiliary Power and Light Electric Rail (LER) Applications" :
UL 1973 | UL Standards & Engagement | UL Standard
UL 1973 | UL Standards & Engagement | UL Standard | Edition 3 | ANSI/CAN/UL Batteries for Use in Stationary and Motive Auxiliary Power Applications | Published Date: February 25, 2022 | ANSI Approved: February 25, 2022standardscatalog.ul.com
UL 9540 is for "Energy Storage Systems and Equipment" and may be for a larger overall system (of components including batteries) that are certified to work together:
UL 9540 | UL Standards & Engagement | UL Standard
UL 9540 | UL Standards & Engagement | UL Standard | Edition 3 | Energy Storage Systems and Equipment | Published Date: June 28, 2023 | ANSI Approved: June 28, 2023standardscatalog.ul.com
There are updates in standards and each jurisdiction can require what they want (and some are maybe requiring full systems to certified at the overall system level and not the component level) but at least for batteries for my area I think I only need UL 1973 (and that seems to be what California tracks for batteries).
In case it helps I am trying to put together a list of UL 1973 batteries by cost/capacity/etc and you can see that here (I just started recently):
UL Batteries
Personally I am looking for lower cost batteries (that are at least UL 1973 Certified) I can get to be approved in a municipally regulated solar install & that would arguably be covered by my home insurance... In looking through various threads I wasn't able to find a listing of at least UL...
Thanks for the info. Here in Texas I have only been asked about UL 1973. Interesting that California is only tracking UL 1973 on it's list of approved Batteries for Solar:
solarequipment.energy.ca.gov
On the Sol Ark site they have a bunch of UL9450 batteries listed, as they are an approved inverter for the connected solutions program. Interestingly, last I checked a couple of months back, while they are an approved inverter, there is no box to check off for Sol Ark on the official application for the program.Thanks for the info. Here in Texas I have only been asked about UL 1973. Interesting that California is only tracking UL 1973 on it's list of approved Batteries for Solar:
If you click on 'Download Excel file' they have 3 columns tracking UL 1973 but nothing on UL 9540 (at least yet) and I will try to check back periodically to see if it is added.Solar Equipment List - CA Energy Commission
It does mention 'Certified JA12' which I think points to 'Appendix JA12 – Qualification Requirements for Battery Storage System' which does say "the battery storage system shall be tested in accordance with the applicable requirements given in UL1973 and UL9540" but every column tracking JA12 says "No Information Submitted" on every row so it looks like they haven't gotten this tracked/implemented yet...
Could the answer for some jurisdictions regarding "which portions of NEC 2020" be none as they are still on previous regulations (especially if semi-rural or small townships)?
Yes, that is why it is important to ask the question at that level. My former little beach town was slow to adopt even the State changes in a timely manner. I am now in a jurisdiction where the County is the entity and they seem to be faster to approve changes.
