What are the options for communicating sensor data to a central point in a medium size building?
I want to build a cheap centralized temperature control. In each room there are about 4 radiators which I want to equip with a few sensors like temperature, light, sound level, and with a radiator valve actuator. Let's say the building has 50 rooms with a wireless network available.
The main requirements are low costs (for the project as a whole), and it should be relatively easy to design and implement. I have some experience with PCB design and micro controllers, and I can ask help of more experienced people. I'm not bound to specific sensors or actuator.
I guess power for the sensors and for the actuator come from a power outlet. Maybe the signal can also travel over the power net.
P.S. As newbie, I feel I could use some help to improve this question. All help is appreciated.