There are a few topics if you have a search.
A few of us use the Fibaro FGBS-222 and a DS18B20 probe.
I have a couple of these Z-Wave devices hooked to probes.
One goes to the pool from my garage next to the pool and one is in my fermenter to monitor brewing temps.
They are mains powered via a brick; I think the range is 12-30 VDC.
These things do a lot more than temp.
