To the OP/TS. I'm US based. In some parts of the US there is residential 3 phase which would either be 208 V Y or 240 delta. Residential is 240 split phase 0r 120-0-120V.
I did some research in Demand side management and it was interesting.
So, yes, we can allow the utility to turn off an electric water heater if you have one or an air-conditioner. The utility also announces "peak energy savings days". You do your part and reduce your peak during x and Y ours, they give you a credit.
We do have "smart metering" and can, but I don't look at your consumption. from what I understand it's Zigbee and cell.
Not sure of all of the rate structures, but some incorporate peak metering.
Canada is primarily hydro and that electricity is super cheap.
You can get furnaces that are dual-fuel or can essentially use a heat-pump or natural gas. If I was in Canada, Canadian logistics might be tough, So, you would heat via heat-pump and then fossel fuels if the outside temperature gets too low.
In the US, it might be more complicated than that.
When you look at stuff from a utility perspective, they have nuclear, Hydro, gas turbines, wind, solar for the most part. Nuclear and hydro isn't easy to throttle.
Wind, you have to take when you can get it.
Solar is interesting from a power company point of view. If the solar farms run by the power company they can use it to locally correct the power factor because of the inverter technology.
Residential solar is mostly grid tie. Not sure if PFC is implemented at this level.
Metering gets weird, because if you use the solar power you produce , it's a 1:1 reduction in your bill. If you produce more than you need, you sell back to the utility at the wholesale rate. So if your working during the day, it really only helps on weekends or if you could "schedule" your dishwashing during the hottest part of the day. Then peak metering and all that other mess starts coming into play.
Solar is nice for the utility because its abundant when the sun is the hottest and the AC is used. At the same time, our brick house acts as thermal storage and it starts to release heat into the home when the sun goes down. That and dinner is also high demand.
We don't know when the utility company is having a bad day, but the utility company predicts and tells us when they expect a bad day. This "peak energy savings" day probably occurred 4x during the summer. You don't have to sign up for it.
The "billing" method that I'm currently using does not offer an "active incentive" except for 4x or so per year. They can turn off the AC which is no big deal. I think the max allowed is like 20 minutes at a a time.
Some incentives like insulation, 98% efficient furnaces, energy audits, LED and CFL lighting will save you money. Personally, I'm not at 100% LED or CFL YET. There is a light in the house that is on an autonomic timer that stays on from 1 hr after dusk t 11:30 PM every day. A LED LED night light that is dark triggered is active 24/7 for the bathroom and a 7W incadesent light that is mostly on under the Kitchen counter when it's dark.
Two reading lights are 3-way LEDs.
One bedroom light is a High intensity lamp (12 V bulb) with a UPS attached. I have a low wattage headboard lamp that I may change in the future.