I do this using Node-red (nodered.org). The basic logic and steps are here Shutdown and restart Hub in case of power outage (Node-red solution) - LONG READ.
The approach that @dJOS linked to is similar. The main difference is that
- Node-red is an external solution (not Hubitat native)
- I shut down the hub after 15 minutes and if the power comes back on, it restarts the hub. I figured that if there was no power, the automations would not work in any case. If the outage is long enough for the UPSs to run out of battery, the hub would restart in any case when power came back.
