They have been around for decades in the US as well. Industry uses far more electricity than residential, so the focus of managing peak use has been factories to shift energy use to off-peak hours, something that the average person would never know about.

On the residential side though, our utitly (Xcel Energy in MN), has a rate reduction program where they installed a power cycling device on our central AC unit that shuts it off for 10 minutes every hour.

I have a bit of a fear about off-peak incentives and tiered prices.

You're still not paying the real-time prices of electricity, for which the purpose is to balance supply and demand.

The pricing systems seem to be designed to be easily understood rather than completely practical.

As a result, the price may jump every day at 5PM, and then go back down at 10PM. But I fear we'll eventually see a time where HVAC/dryers/fridges/etc turn on full blast at 4:30PM and stop entirely at 5PM, then turn on again right at 10PM, leading to grid instability due to the sudden change in usage at exactly one point in time.

>But I fear we'll eventually see a time where HVAC/dryers/fridges/etc turn on full blast at 4:30PM and stop entirely at 5PM, then turn on again right at 10PM, leading to grid instability due to the sudden change in usage at exactly one point in time.

If you know it's going to happen and you have a decent grid you can manage. The UK supposedly has a 3GW spike in power draw every time the BBC's soap opera goes to comercial. That's a sizable chunk of total power in an island grid that doesn't have the rest of Europe backing it up.

http://www.geek.com/news/tea-time-in-britain-causes-predicta...

I'm in Chicago and I pay real-time prices, averaged by the hour. The program is entirely opt-in and has been around for about 4-5 years now.

You're right that the increasing number of grid-connected devices could lead to problems like this, especially as more and more appliance makers start to add this ability. At the moment I've seen grid-enabled devices used to back down on electricity use during peak times. ComEd offers a GSM-connected box to modulate your A/C compressor during brownout times.

But I've tinkered with a thermostat that superchills my house when the price dives into low or negative space. I guess I never thought about what could happen when 1,000,000 homes do the same thing. Law of unintended consequences I guess.

No. The US has had off-peak pricing for a while. Many appliances have delayed-start buttons so you can set them to run when electricity is cheaper and forget it.