This is gonna be big. IoT will be the next wave of innovation as far as tech is concerned.
We're already seeing this with all the connected homes and wearables. I had a former roommate that was building a company around an automated window opening machine that would automatically open your windows when it's either warmer or cooler to save you money.
E.g. You set the house to cool at 70, it's currently 72 in the house but it's 68 degrees outside. The machine would turn off your cooling, open the windows tinup until your house got to 70 degrees. It'd do the same for heating as well. The value prop is the savings you get from turning off the cooling and heating.