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duxup

In Minnesota I signed up for a device that the electric company installs on the electrical connection to our AC unit.

Between 2pm and 7pm (I think those are the hours) the company can shut down your AC for 20 minutes at a time.

I can think of twice in 15 years that I noticed it. For that you get a small discount on power June through September.

Good deal.

I like that this allows for more immediate / targeted impact for folks managing the grid.

Something like this for car charging (or even just slower charging?) might be useful?

https://mn.my.xcelenergy.com/s/residential/heating-cooling/s...

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I signed up for such "brief" interruptions with our local power company when it first rolled out. A few weeks later they cut off AC the entire day during one of the worst heat waves in the area. Customer service completely unresponsive. House temperature rose to the upper 90s on the lower level. I had it deactivated after that, and never reactivated it.

Someone screwing up was my concern when I signed up but it has worked well for us.

Yeah, probably a bit safer in Minnesota too ;)

AFAIK, there was no recourse either since it was sold as brief interruptions, but apparently it wasn't a screwup - they really had the option to just leave it off all day if the grid was really struggling.

And, while I appreciated the need, I wasn't going to be the sacrificial lamb next time that avoided the rolling blackouts. At least in a rolling blackout I'd get some AC.

Yeah, if there is a program it has to be appealing and run well to work.

Ours has worked well but going too long is just going to turn folks off big time. It would me for sure.

I'm curious who your power company is and how long ago that happened. If you're in the US do you happen to know if FERC got involved?

Utilities and grid operators that run retail-level demand-response programs typically cycle air conditioning units by turning them on and off throughout the day or by setting the thermostat a few degrees higher in more modern systems. I've never heard of a demand response program completely shutting off anyone's air conditioning for more than an hour, that sounds like either a technical failure and/or a wildly incompetent demand response program. Either way it's frustrating because it gives responsibly managed demand response programs a bad reputation.

Having said that, if the peaker plants are running full tilt and the demand response program isn't able to curtail enough usage then the next step is rolling blackouts. Is there a chance that's what happened, or did the rest of your power remain on?

Rest of power was fine, no rolling blackouts. Let me see if I can find any news articles from the time. I wasn't the only one it happened to, and apparently despite how it was sold, contract allowed for longer periods.

[edit] https://www.baltimoresun.com/bs-mtblog-2011-07-bge_flipflops...

That's awful, if I had your experience I wouldn't use demand response either.

Now I'm also curious whether your contract was directly with your utility or through a 3rd party energy supplier. Where I live the non-utility energy suppliers can be a bit dodgy and push misleading contracts on retail users but they're still somewhat regulated so I am skeptical a contract that allows them to completely shut down everyone's AC for the entire duration of a demand response event would be approved here.

But I've heard horror stories about non-utility energy suppliers in other ISOs (like Texas' ERCOT) gouging customers, abruptly shutting down, or just generally being wildly incompetent.

It was the standard state regulated area utility.

What was the duration of interruption for you?

basically the entire day. a little after sunrise as it warmed up, to after sunset. There was a couple of extremely brief intervals where it started back up, but basically an entire july day.

The UK smart charging regulations require all new domestic electric car chargers to be "smart." I.e. connect to a platform that tells them when they may or may not charge. They must have default schedules that avoid peak usage times if they are not connected. They must randomise start times somewhat so that there is no sudden surge of demand when the off-peak period starts, and so on. Many of the chargers on the market were doing these sorts of things already, anyway.

That is interesting, can you override the charging times if you have an emergency?

Yes. The law is all about default behaviour. The customer has ultimate control.

Nest does this in conjunction with local energy provider during "rush" hours. It will cool the house lower than normal, then raise the AC temperature limit, usually between the hours of 14-18. Actually get paid back for it.

What’s the discount? We have a similar device in northern Illinois and only get $10 off four months each year.

15% June through September.

Updated my post after I looked it up. I got a few details wrong initially.

No problem. I guess that would average out similarly, and be a lot more for some people. With solar, not so much, of course, but the load is also mostly absorbed. Interesting.

We have the same thing for shutting down our water heaters (geyser) - it is called a ripple control - sends a signal down the electrical circuit to houses from the local substation when there is power supply constraints.

Also works with electric boilers and ripple switches. They can hold temp for 24h+ so you don’t easily notice if the supplier kills it for a couple hours

It's great that you're doing your part to help the grid.

But we don't need to live life in low-battery mode.

There is another option.

Well we don’t because it is hardly ever used.

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