This is a very important topic. One of the most considerable research areas which is relevant to this topic is " Smart Grids". Smart grid, which is mainly about how to utilize electricity in a much better fashion, cannot be realized unless there are Smart Homes, that can interact with power plants.
Well, I am currently involved in developing a smart home system using IoT (Please visit www.thingsaccess.com). I have found two ways to do that. First, in order to implement IoT in true sense, every device or thing at home should be directly accessible which can be done using CoAP with 6LoWPAN (of course through Border Router). Second, the conventional technique of using gateways and restricting the devices behind the gateway. So the gateway talks to the rest of world for remote access. Here people implement their propriety solutions to access or control the devices remotely using different protocols or their own solutions.
The true implementation of IoT in first case still requires the mature hardware and software. I have gone through many IOT operating systems and each of them has lot of issues in terms of compatibility with different hardware, wireless interface and capabilities. So the short cut still is the second approach.