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Arizona Trialing System That Lets Utility System Control Home A/Cs
AzTechGuy writes "Arizona Public Service Co., Arizona's largest power company, is implementing a test program that would put customers' thermostats under their control to help balance power needs during critical peak usage times. APS will be able to remote control the customers' thermostats to control power draw from their A/C when there is a critical power transmission issue on the grid. Customers will be able to override these settings if they desire."
It seems like a convenient method of limiting brown-outs. The privacy implications may be enormous for some but for others it will appear to be a good idea particularly since folks can override the system.
Idaho power opted for something far simpler several years ago. An exterior radio controlled override that cuts off the compressor motor (most of the load) for a maximum of 15 minutes while leaving your interior blower motor running. You don't notice a thing. If you happen to have two AC units they are alternated. This allows for much simpler peak load control of the power grid and doesn't torch off the customers.
Roughly, the first 90% of the load cost is X, the next 9 to 10% cost is 10X. If you need to buy a remaining 1% on the spot market during a squeeze, the remaining 1% will cost 100X.
Being able to shed that top 1% can make a big difference.
"To those who are overly cautious, everything is impossible. "
Yes you can override it. Seams like every moron believes that they are giving up control of their thermostat and that they just shut it off. What they do is raise the temperature by a few degrees so AC units are not working as hard and as much. It's a small reduction of power but multiply it by a few thousand homes and it's enough to shave off the peaks during high usage. And as far as I'm aware in Ontario, they have only send the signal a few times each year so it's not a daily thing.
The credit on your bill is just a incentive to get the thermostat. The real saving is when you program you stat so your ac isn't cooling the house all day when your not around instead of having your old manual stat set to 15 deg C all day long.
While I can't quite tell if you're trolling or simply greedy, there's a certain logic behind your argument.
Right now, electricity cannot be economically stored, so generation capacity has to equal peak demand, or else someone gets browned out. Utilities go to elaborate lengths to estimate future demand, based on housing construction, industrial zoning, winter temperatures, summer temperatures, etc. They build right to the edge of what their predicted demand will be, and rely on peak plants to supplant their generation capacity during those times when they've guessed wrong. But those peak plants charge 30X or more than the average generating rate, so there's strong incentive to not use them.
What they're doing by all this penny pinching and building right to the edge of demand is they are thinning the tolerances. In the past, many things worked well or lasted long simply because they were massively overbuilt. For example, rather than fully study and understand the material strength of an aluminum engine block with steel cylinder sleeves, they cast the engine block out of iron. Rather than measure and predict the load to within 1% of future demand, they built a plant with double or triple the planned capacity. Those systems lasted a long time as a result, and people got very used to the high availability of their services.
And in case you were serious, the correct economic answer is yes, they should offer you the extra capacity, as long as you're personally willing to pay the price. My electric company offers demand pricing. Normal pricing is $0.11/kWH for household use, regardless of what you're using the power for. But if you willing to let them control your air conditioner, you pay only $0.055/kWH for all the electricity your A/C consumes throughout the year, plus they discount your bill by $10/month for June, July and August. Control consists of a rolling 15-minutes-on/15-minutes-off duty cycle during peak demand. My heat pump was controlled for a total of 90 hours last summer, and the difference was hardly noticeable. When my heat pump was cut in the winter, the gas furnace kicked in as needed. I save several hundred dollars per year on this program.
John
If you can override it, essentially all they're doing is informing you of power demand, not monitoring you without your consent or forcing you to do anything. Explain what oppressive totalitarian privacy-violating government regimes (i.e "Big Brother") have to do with any of this.
Perhaps they should just send me an SMS then - "We'd like to turn off your A/C for the next 90 minutes. Our bid is a $5 credit. Accept?"
Residential systems usually don't have heat storage, but larger systems, with chilled water, often do. Some even make ice at night when power is cheap, to be melted during the day. It would be helpful to have a few hours advance notice of a hot period, so that the system could chill down an insulated water tank for use later.
Power companies generally have a load curve planned a day ahead. That info is available; here's PJM's dashboard, which tells you far more than you ever wanted to know about the power grid for the northeastern United States. (Load right now: 55,292 megawatts. 1,896 megawatts of that is wind power. Spinning reserves are 2,274 MW. Current trouble report: "As of 09:30 hours, a Non-Market Post Contingency Local Load Relief Warning of 11 MW in the Rachel Hill area of FE (PN) has been issued for Transmission Contingency Control. Post Contingency Switching: Open Roxbury at Shadegap, Close Threesprings at Shadegap, open Curryville at Claysburg, open Snakespring at Bedford North." Tomorrow's estimated peak is around 71 gigawatts, expected at 17:30 hours.) The estimation system uses historical data and weather reports, plus bid info from really big users. So one can plan a day ahead if your HVAC system has heat storage.
Routine control is exercised by financial means - all the players submit bids, which have a time range, a low output and price, a high output and price, and a ramp value. The control center crunches on these and decides who generates how much power. Large power buyers can bid, too; they have the option of saying how much they'll cut their load as the price rises. A big data center might choose to be a market player. When there are troubles, the control center can take "non-market actions", like the one above, but most of the time, the outstanding bids determine who does what.
California went too far in deregulation, and had electricity auctions every half hour at one point. There were brokers and dealers who were pure speculators, and this affected live power operations in real time. That caused so much churn that there were blackouts. So now, bids are for a day ahead, and the matching of supply and demand is algorithmic. All this data is public, to keep the markets honest. That's why PJM offers such detailed data about their power grid.
They got this on my hot water....and I can't opt out or over ride. They report only using it for about an hour at a time, and only 2 or 3 days a year for the last few years though. Yes, peak demand during summer afternoons.
Phil
Just out of curiosity, how does that work? You can't override a system that sits in your house?
What do you get out of this deal? Can you just not pay your bill during your peak expense season? Quid pro quo, you know?
Most states, in addition to rebates and grants ( and federal ones) will give you extremely low interest loans.
So that 30k system ends up costing you about $15k over 7-10 years, or $150 - $200 a month. Then, you have basically no more utility bill, ever. (and still have 18 years of warranty on your solar panels...)
What are we going to do tonight Brain?
After all the tax credits and such, our 7kW system was about $8k in Arizona. It makes about $1300/year in power at present electric rates, and has a 25-year warranty. If you can afford it, it's beats the living crap out of putting your money in a CD, even assuming we could get something more like historical CD rates these days.