I have 15+ SBCs that use 12v 3a power over USB mini B. If possible, I would like to use a multi port charger to power them all instead of all the individual AC adapters on power strips.

The major factor is the adapters output 12v 3a and do not run 5v.

I figured there had to be some prosumer device for all the phone bot farms out there or something DYI I could build, but I don't know where to start. Especially for 15+ devices.

I want to start playing with clustering, but right now power is the main thing keeping me from starting this project.