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Making a Learning Thermostat
OzPeter writes "As reported in WA Today, Tony Fadell of iPod fame has been using Nest Labs to design and build a thermostat that learns how you live in your house by following how you manually change the temperature. Once you have taught it how to behave, it then can schedule temperature changes that suit your lifestyle, and help you cut down on energy costs."
Don't let women use this thing. It will only learn two settings: the maximum temperature setting and the lowest temperature setting. At least that's how the females in my life use them.
Better known as 318230.
Cold person irrationally turns thermostat up to 80. Angry frugal person retaliates by turning down to 50. Repeat 20x/day.
Ah, but the thermostat also has the information of what the temperature actually is when they turn the dial.
Cold person turns it up at temp X, frugal person turns it down at temp Y.
X is too cold, Y is too warm. Good compromise temperature is between X and Y.
80 & 50 are irrelevant.
The whole point of this rethink is to look at heuristics like that. Not just to learn, but to be intelligent about it.
It is a well documented fact that in some office environments, fake thermostats that the workers can access improves perceived comfort and reduces calls to maintenance.
Or does it learn how long it takes me to get dressed and walk from the bedroom to the thermostat?
If it's occurred to you in the few minutes between learning about the device and posting here, why would you imagine that it hasn't occurred to them? There's no reason why it can't work out which is the morning increase, and assume that in future you want that temperature 10 minutes earlier in the day, or 5, or 20, depending on what their research in the field has found to be satisfactory for most people.
And if it uses motion sensors to decide whether or not I'm home, it's either going to think I'm never home since I don't go past the thermostat much in my day-to-day activities, or it's going to think I'm always home when it senses the dog going to her food dish.
They say the best place for thermostat is in a hallway. People should be passing that from time to time. But they do say to turn it down yourself hen leaving and up when you return, at least for the first week, to give it a good start on working out your patterns.
And placed at the normal thermostat height, the detector isn't set off by dogs. That's a FAQ.
I'd much rather have a thermostat with an easy to use UI than something that tries to be smart.
I've never seen an easier UI than this one. There's only one control and that's a temperature dial. Personally I'd far prefer one that's smart.
I don't see how a thermostat on a wall can do a good job.
Ah well, if you can't see it, then obviously it doesn't work.
"No wireless. Less space than a nomad. Lame."
Really, I was surprised, but I have one on my A/C. So my A/C is a dual stage unit. Basically it has a bypass so that when it doesn't need to put out so much cooling, it can work the compressor less, spin down the fans, and so on. When needed, it can use full capacity. It is a 4 ton unit that effectively has about a 2.5 ton mode. Good for saving energy. Most days all you need is the first stage, even in the desert.
Well the thing is, the stage use is determined by two degree bands, temperature deltas. The first you set between 1 and 6 degrees. This is how much the temperature can swing before the unit engages. So if the degree band is 3 and the thermostat is 75, the A/C will come on at 78 (or the heat at 72 if in heat mode). The second one is another two degrees fixed. When the temperature is more than the first band plus the second, the thermostat engages the second stage of the A/C. So if set at 75 with a 3 degree band, the second stage engages at 80 degrees.
Needless to say the thing cools a hell of a lot more when fully spun up. So you really can make it cool down faster by setting the temperature lower.
In fact, I have to when it is really hot. When it is very hot, like 105 or above out, the low stage is really only enough to maintain the temperature. It cools as fast as heat leaks in (that is the design idea more or less). So to actually get it to cool, I have to kick in the 2nd stage. Means if I want 75, I set the temperature lower, until it hits 75, then set it to 74 and the A/C will continually run until the outdoor temperature cools off enough.
And yes, it is more efficient to run continuously in the low stage than cycle on and off in the high stage.