Ok, so I have a Arduino Nano with a humidity/temp sensor and a Bluetooth module.
The whole project needs to be relative small to fit in the plastic in the wall (https://www.yousave.dk/images/billeder/5703302152686-p.jpg)
All I need now is to power the device, and I'd prefer a solution without batteries, unless I get can a year of battery life out of it.
I've thought about doing it over a Ubiquiti PoE+ switch, but I'm very open to other solutions.
What is a good way to power this given that the power source is 5-10m away?