Massive, Explosive ... Micro-Curtailment

July 06, 2009

This is a story about how you can curtail people's AC without them noticing, and the big opportunity this represents to do a little micro-curtailing.

We had an air conditioning problem in the pretty new building we'd just turned over (fried a variable frequency drive motor on the building's only air handling unit). The building occupants were sweating, we were sweating. 

We fixed the problem, but the following morning it was already 75 degrees in a couple of rooms (in Texas in June); temperatures were forecast above the century mark that afternoon. Our panicked owners were concerned that we hadn't really fixed the AC, and that those rooms would get into the upper seventies as they hosted a national theology conference. It was simply unacceptable that they'd have rooms with temperatures in the upper seventies.

The building automation controls tech that was working on our AC problem advised that electricity was being curtailed campus-wide (an arrangement that lets the utility reduce electrical use across an organization to balance supply and demand on particularly hot days). Thermostats across campus would be reset to 77 degrees; everyone would be a little hotter that day. I called the owner's construction project manager to warn her that a curtailment program was in effect (so she wouldn't think we had more AC problems if she got calls from hot, angry building occupants). So, here's the micro-curtailment opportunity:  it was already 77 degrees in her own office and she didn't know. She did not even notice.

All the fussing about room temperatures getting into the upper seventies, and here it was happening by design everywhere on campus and people didn't seem to notice. With the coming Smart Grid we'll be able to curtail more broadly, and yet at the same time in an even more fine-grained way. To explore this further, a little breakdown of the post title:

Massive:  With the Dumb Grid, curtailing is currently mostly done with larger organizations. The Smart Grid will open up curtailing to small businesses and residences (for a taste of this thinking, see here). Since the real estate held by small businesses and residences is massive, the curtailing opportunity is likewise massive.

Explosive: When people realize the money to be saved, this will spread like wildfire. Even without the Smart Grid, organizations can make money by curtailing their energy use. With the Smart Grid, the opportunities to make money (that is, to save money) will grow. Companies and families that don't do this will have the 'Fool' stamped on their figurative foreheads.

Micro-curtailment: The opportunity to tailor energy use to the room, to the minute, to the device represents the opening of a staggering volume of nooks and crannies to curtail. Smart Grid micro-curtailing will be the iPod of electrical power production. iUtilities. The fact that individuals will be able to control electricity at this level will induce them to play. In the example above, the organization would have the power to override curtailment at the building where the national conference was being held (to ensure their out-of-town guests' comfort). Actually, they could have chosen to override, except at Rooms 102, 106 and 215, and only for the hours of the convention, which knocked off at 4 pm.

Micro-curtailment, coming to a building space near you.

Photo: Cecilia Condal on flickr

Comments

[eric]

"Actually, they could have chosen to override, except at Rooms 102, 106 and 215, and only for the hours of the convention, which knocked off at 4 pm."

Nitpick: But this building had central air -- so they actually couldn't have done that. So "micro-curtailment" runs up against the desire to achieve economies of scale, thus limiting its impact on consumption.

[Rainer]

Curtailment is the same thing as rationing. Just a fancier word that seems less negative. Not for or against this, but let's be honest.

[Chris Davis]

eric, the building has thermostats and variable air volume boxes, which coupled with the building automation control system, allows for control of individual rooms, or at least the spaces served by the thermostat.

but really, the rant in the post above isn't so much about what is, it's more about what is possible with a smart grid. what kind of micro-tuning can we do if we decide it makes sense and we want to do it?

[Mike Giberson]

Rainer: No, this isn't "rationing with a fancier word", or at least it shouldn't be.

I guess "rationing" in this context would be the utility turning down a building's energy use in order to keep the electric power system operating reliably. In a smart grid vision for micro-curtailing, the local utility would have a contract with the building operator, which could get paid for reducing usages (and micro-curtailing used to reduce use at minimal loss of value to occupants).

Or, perhaps the retail electric power supplier to the building is charging a real-time price and the building manager decides prices are too high and wants to cut consumption to reduce the energy bill. Again, micro-curtailing is a technique for trying to reduce energy use with little loss to the occupants.

Companies like Site Controls are already doing this kind of energy management with their customers.

[James H]

I'm not sure why I need a smart grid to control the thermostat in my house. I mean, I already have this thermostat, where I can adjust it anytime I desire. I have complete control over my domain. What you're missing is that the smart grid allows OTHERS to have control over my home settings. They must be smarter than me, and can decide better than I can what temperature is best or when to run the dishwasher. No thanks.

[Chris Davis]

James, I imagine a Smart Grid where you retain control, but "they" can be smarter than you because they (the Smart Grid system, whatever that ends up being) are continuously in contact with dynamic changes in supply and demand and pricing and so could figure out when it is best to run the dishwasher. You would always have the option to override the deals you have set up, or the choices they offer.

One challenge would be the opportunity for utilities to get to the consumer because pricing would be so fluid as it follows supply and demand. The counterweight, if the system is designed properly, would be an ability to shop on-the-fly for the best choice from multiple suppliers (that is, don't allow utility monopolies).