Low power wireless switch

Hello everyone,

Sorry about my noobie question but here it goes: I am trying to control the rainbird 9V latching solenoid valves on my garden with arduino and esp8266 but the catch is, there is no electricity where I can place the module. My plan is to place arduino inside home, connect it to internet with ethernet shield or esp, send the command to the valves with RF. The issue is, I dont know what to use to receive data from arduino with RF and control valves with relays. It needs to be super low power so it can run at least a year on a 9v battery but it needs to send data in and out to arduino. Thanks a lot for any help!

What will you use to power the solenoid? perhaps you can use the same source? That would make selecting your solution easier.

Yes I am thinking to use 9v battery for both. I will need a small dc to dc regulator for the rf module most probably but my plan is to use a single 9v battery for both the rf module and solenoid valves.

Theres no such thing as a super low power receiver as they consume around 3 - 4 ma or more all the time.
That will rapidly drain a 9V battery.
Also how often to the valves need to operate and how much current do they draw.
Consider looking at solar power.