Live data from Hacker News

Smart thermostats inadvertently strain electric power grids

news.cornell.edu

121–130 of 226 posts

Re: Smart thermostats inadvertently strain electric power grids

#121

Earlier quoted context omitted.

I want floor vents that are wireless networked, coupled with occupancy, CO2, and temperature detectors. They should have the smarts to figure out when to open and close, such that rooms are never stuffy, and never too hot or cold.

If you setup water heater / cooled systems using the in-floor (sometimes in-wall) pipes, they get that almost for "free" - you can turn on and off zones very easily.

That's a fine idea when building a new house, but untenable for a house that is not being thoroughly renovated. My forced-air HVAC system is built-in, and replacing the register vents would run me under $2K at $100 a pop. Ripping up my flooring and installing in-floor heating would cost me tens upon tens of thousands of dollars.

Re: Smart thermostats inadvertently strain electric power grids

#122
post #107

Earlier quoted context omitted.

It does work, though. Nest's program pre-cools to get you through the hottest hours without having to kick on the AC, moving some of the region's demand from the 4-6pm slot to the 2-4pm slot. I find myself going "huh, it's getting a little warm" at about 5:45pm, at which point I check and remember it's a "Rush Hour" session.

Does precooking really work? I’d assume it would have to cool my house down below 65 to keep it below 80 all afternoon. 111+ days are brutal in certain rooms even with both ACs set to 76.

Does precooking really work?... 111+ days are brutal

Not every solution works in every situation. That doesn't mean it doesn't work, it just might not work for you.

(Posted from a location that was 108° last week.)

Re: Smart thermostats inadvertently strain electric power grids

#123
post #88

Earlier quoted context omitted.

I don't want to pay for them but I do wish I had automatic windows. It would be so nice if my windows automatically opened if the temperature outside was a few degree's cooler than my house and I was in "cool" mode. If it took the wind into consideration, even better. My house cools off so nicely when I open windows on opposite sides, but I have to remember to open and close them at the appropriate times and I have t…

Adaptive vents, too. Why cool the whole house when I'm going to be in two rooms for the majority of the (hot) afternoon before opening the window to the bedroom in the evening?

That's essentially what zoning is, most commonly used to heat/cool different floors of a house separately without having to have multiple furnaces and AC units. If I understand correctly, you want the shut-off flaps or gates as close to the blower as possible for maximum efficiency—just shutting off the vents at the ends of the lines would mess with pressure and airflow in the rest of the system in undesirable ways.

Re: Smart thermostats inadvertently strain electric power grids

#125

Smart thermometer manufacturers could solve this fairly easily by randomizing the start time. Instead of them all turning on the heater in the winter at 6am, they could i.e pick a random start time between 5:30-6:30 by default.

Cron has a bunch of this kind of thing built in for stuff that's known to touch the network, like automatically running apt-update in the background. You don't want millions of Ubuntu machines in each timezone all hitting the CDN within seconds of each other. I think Google Maps does it too with routing— it adds a bit of fuzz so that it doesn't send literally every car down path A when there's a path B that's nearly…

systemd.timer [1] also has AccuracySec, RandomizedDelaySec and FixedRandomDelay.

[1]: https://www.freedesktop.org/software/systemd/man/systemd.tim...

Re: Smart thermostats inadvertently strain electric power grids

#126
post #85

Earlier quoted context omitted.

If you can feel that your walls are warm I don't think that's good enough insulation. The whole house fan solution is great though.

i have walls insulated according to california build code. it's not really possible to add more insulation to them, unless you rip them off and do spray in insulation. insulated attic with radiant barrier and insulated floors. i just checked with IR camera, most of surfaces in the house are now 22C-24C. After a few days of 40+C walls ill go to 25-26. some walls (south side of house) even higher. There are few little…

it's not really possible to add more insulation to them, unless you rip them off and do spray in insulation.

Actually, it's possible to inject foam insulation into walls without ripping them off. It goes in through small holes, or through utility boxes. Plenty of companies do that. I've even seen it advertised on TV in California.

Re: Smart thermostats inadvertently strain electric power grids

#128

Ecobee has eco+ which has "Community Energy Savings" [0]. It was just way too intrusive. It seemed to be a reactive system vs proactive. Technology Connections goes into this more [1], but I believe they should be providing a system that proactively cools when there is less demand _prior_ to an expected increase in demand. Effectively using your house as a "battery". When I had it enabled, I was _always_ too hot (in…

>Sorry, not sorry: I'm not willing to sacrifice my comfort for the ~$10/mo incentive. Hey, but at least you don't use plastic straws, right?

The plastic straw thing confuses me. I'd like someone to explain to me how anything besides the random runaway straw gets into the ocean. I live 60 miles from the ocean. We're people throwing them into storm drains that flow to the delta that flow to the ocean? We're people in San Francisco traveling to the beach and throwing them into the ocean? Couldn't we focus on not littering instead of legislating things like straws?

Re: Smart thermostats inadvertently strain electric power grids

#129

Earlier quoted context omitted.

I don't know how the smart thermostat is supposed to know your behaviour unless you tell it, which means taking it off the default. I had to tell my thermostat explicitly when I wake up.

With room occupancy detection, it should start modeling likely HVAC needs - able to predict accordingly, and adjust power use & timing jitter accordingly.

Ah, that's another level of smart than I was thinking of and requires integrating motion sensors, but I do suppose that would enable it.
Post reply on HN