I'm not an HVAC engineer, but I imagine that efficiencies would go down significantly with multiple smaller unit, as opposed to a single larger unit. In addition, you'd be talking about electric heaters (as you probably don't want point-of-use gas-fired heaters pumping CO into your living room), which tend to be less efficient than fuel-fired heaters, mostly due to the fact that, ultimately, you're using heat to generate electricity, which is shipped across the country, and then used to generate heat, with losses all along the way. I'm sure that the power plants are more efficient at gathering heat than a residential heating unit, but still. Of course, if your infrastructure moves to (far?) less fossil-fuel, there may be other considerations.


My understanding is that the transmission lines are huge enough that their capacitance is more than able to deal with the small amounts of energy we're talking about being pushed back from consumers. In addition, power companies already deal with varying consumption rates; there's no reason that they can't just include that information in their procedures.