I'm a little confused what the benefit of doing that would be. When the power is out, you will not be able to control any devices because they will be offline. If you have a generator, the CM15A would work (at least as well as it can based on the quality of the sine wave from your generator). But If you have quality power provided by the generator, your CM15A wouldn't need a UPS. It seems like unless you are also putting X10 modules behind the same or other wirelessly linked UPS it wouldn't make any difference. I don't run my CM15A with a battery because it's connected to a RPi all the time but I guess I don't see the use case. Otherwise, as others have said, the controller should work.