I need advice on powering at least 4 Pis (or more) from a single supply. POE is not possible in this use case.

I see 2 options:

1. USB-A power strips/hubs
2. USB-C PD power plugs, typically limited to 4 ports

For USB-A supplies, I tried an Anker AH231 which supports 10A total, with "USB-A--> USB-C" charge cables. Even while "idle", the Pi4's occasionally show the lightning bolt warning. I suspect all USB-A powered hubs would do the same..?

For USB-C supplies, it looks like I'd need something like the Anker 547 which is $110 and seems overkill. Willing to consider other brands but has to be Ul-Listed or ETL (homeowner's insurance requirement). Supply has to be "leaded" (not hanging off an outlet) for reasons.

Does anyone have specific hardware that worked for them?

Also - is a voltage warning usually handled successfully by throttling? Or is there a good chance the condition invalidates a software test?

UPDATE1 - ALMOST... but not ETL/UL-Listed (legal and liability): * https://www.ugreen.com/products/ugreen-nexode-200w-usb-c-desktop-charger?variant=39815557185598

UPDATE2 - What I'll have to do for now is a 1U PDU internally mounted, backwards or use the Anker USB-C supply and ignore/disable any lightning bolts. At this time, NOBODY makes a "certified" multi-port USB-PD like the ugreen I link above. Bur It's only a matter for a true USB-PD power strip..

UPDATE3 nov 2022: This is GOOD, meets both requirements (capable, AND safety/liability meaning UL-Listed): * Anker 525 https://smile.amazon.com/Anker-Charging-iphone13-Extension-Accessory/dp/B0B3HW6MPD ("Perfect" would be more ports, but two of these will cover it. Cheers.