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Smart thermostats inadvertently strain electric power grids

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Re: Smart thermostats inadvertently strain electric power grids

#181

Post by jffry »

jrs235 wrote: post #171
hachari wrote: post #165

Earlier quoted context omitted.

A dehumidifier is essentially an air conditioner that dumps heat back into your living space. What you are doing sounds inefficient.

Yep. They're adding heat to the inside of their home. They need to use an AC unit to remove the moisture and pump the heat outside.

I do have an air conditioner (well, an air-source heat pump), but it doesn't adequately remove enough moisture before the indoors gets too cold. It's possible this is not properly sized, but I cannot change it because I rent.

In my case I did some tests, and the additional power usage of the dehumidifier is way more than offset by the power savings I realize by running the air conditioner less frequently. This only works because the dehumidifier enables me to be comfortable at a higher indoor temperature.

Re: Smart thermostats inadvertently strain electric power grids

#182

Post by dimal »

LazyMans wrote: post #89
taylodl wrote: post #71

I really don't like the strategy of super cooling in the morning. I prefer fresh air instead. I throw the windows open wide and let all the cool morning air in. By midmorning I'm usually starting to close those windows because the outside air is getting warmer. By mid afternoon I'm closing all those windows and turning on the AC and setting the temperature to 1 degree (Fahrenheit) cooler than the current room tempera…

I predict in certain areas, "free cooling" systems will become the standard. These are system which do just what you talk about automatically. When there is a need for cooling and exterior air is cool enough, supplement supply air with air from the outside. This way your AC system load is reduced, or if cool enough, the compressor doesn't need to run at all to remove heat from your home by replacing it with cooler ai…

I've been wondering why my Nest thermostat doesn't already have an option to do this. I can turn on the fan manually, but it's not smart enough to do that automatically when it's cooler outside than it is inside.

Re: Smart thermostats inadvertently strain electric power grids

#183

Post by Nextgrid »

mcronce wrote: post #144
baxtr wrote: post #110

Earlier quoted context omitted.

Someone who works at a bar told me recently that they “discovered” long tubular pasta (forgot the exact name) to be the best organic straws. PS: You’re welcome.

The bar I frequent uses straws made of biodegradable material derived from sugarcane - they last a lot longer than paper straws, but ultimately are water soluble and will dissolve after a day ish if submerged. They obviously cost a lot more than plastic, but the user experience is just as good without the forever waste.

From an ecological point of view it really depends how much carbon is emitted during manufacturing & transport.

Landfills aren’t actually that bad when it comes to getting rid of waste. If you expend more carbon using the “eco-friendly” straws than using the normal ones then it’s not worth it overall.

Re: Smart thermostats inadvertently strain electric power grids

#184

Post by jwilk »

mikepurvis wrote: post #25
yellow_lead wrote: post #4

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…

> Cron has a bunch of this kind of thing built in

At least Vixie Cron doesn't support anything like this.

Each cron job that needs it has to implement it on its own, e.g.:

https://github.com/Debian/apt/blob/2.5.1/debian/apt.apt-comp...

Re: Smart thermostats inadvertently strain electric power grids

#185

Post by mason55 »

google234123 wrote: post #103
LazyMans wrote: post #86

Earlier quoted context omitted.

Where do you live? I'm just curious because I can't imagine living at 78F anymore.

78-80 doesn't feel to bad in a dry climate imo

Yeah we live in the foothills in Colorado at 7700 feet elevation. Typical summer day is 85 degrees and 20% humidity and we don’t have AC.

It gets warm but fans are enough and I have a portable swamp cooler for when it gets really hot.

Re: Smart thermostats inadvertently strain electric power grids

#186

Post by solraph »

rblatz wrote: post #107
ceejayoz wrote: post #59

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.

I can't speak for the specifics of using a Nest, but pre-cooling a house earlier in the day is definitely a more efficient use of power.

Earlier in the year in Australia when day time temperatures were 35°C-40°C (95°F-104°F), waiting until midday to turn on the AC would mean using another 10 kwh more than if the AC was turned on at 9am.

Granted, this is an new Australian house which means it's built to standards about 30 years behind what you would expect for a first world country.

Re: Smart thermostats inadvertently strain electric power grids

#187

Post by slavik81 »

jffry wrote: post #178
hachari wrote: post #165

Earlier quoted context omitted.

A dehumidifier is essentially an air conditioner that dumps heat back into your living space. What you are doing sounds inefficient.

The dehumidifier does use power and produce heat which must be removed from my apartment by the air conditioner. Because it's less humid, I can maintain a higher indoor temperature and still be comfortable, meaning the air conditioner needs to run less. Do I use net less energy? In my case, yes, but your mileage may vary depending on your equipment, insulation, etc.

He's saying that you have two air conditioners: one that vents heat inside your house and one that vents heat outside your house.

Your dehumidifier and your air conditioner are mechanically identical. The only difference between the two is where the waste heat goes. The exact same device is called a 'dehumidifier' if the waste heat is vented indoors and an 'air conditioner' if the waste heat is vented outside.

There's not really any efficiency gains from running a dehumidifier to reduce air conditioner use. They both use the same power and have the same effect on the absolute humidity, so you might as well just run the air conditioner (unless you want it to be warmer).

Re: Smart thermostats inadvertently strain electric power grids

#188

Post by moralestapia »

saurik wrote: post #98
moralestapia wrote: post #95

Earlier quoted context omitted.

>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?

Why would you expect someone who isn't willing to sacrifice their comfort for a $10/mo incentive to sacrifice their comfort for a $0/mo incentive? Deciding "I don't like this person's ethics" doesn't mean "this person is suddenly inconsistent": you need to check your knee-jerk responses :/.

It was a sarcastic remark to his/her selfish attitude towards sustainability.

"Sorry, not sorry" multiplied by 1,000,000x and through the decades is what got us (all) in a climate emergency.

Re: Smart thermostats inadvertently strain electric power grids

#189

Post by smileysteve »

wongarsu wrote: post #52
bob1029 wrote: post #17

The power grid is a very complex thing, and I strongly believe that demand management is an important component for stability. There are ways we could better organize our HVAC fleets to provide near-equivalent levels of comfort. The current proposals really suck though. Storage is a big deal that seems to be the focal point of most of the renewable/non-renewable debate, but there are other concerns that are discussed…

I wouldn't be surprised if "power plants" that just provide inertia pop up. Basically flywheel storage, but with the intent to keep the flywheel at a fixed saturation level to stabilize the grid frequency. But we are at an interesting point in time where "smarter" devices make the addition of demand management easier than ever, and at the same time less predictable power generation makes demand management financially…

This is some substations.

Re: Smart thermostats inadvertently strain electric power grids

#190

Post by asfsaf »

wiredfool wrote: post #105
seiferteric wrote: post #92

Earlier quoted context omitted.

It's funny that I have seen several anti A/C articles and several pro Heat Pump articles in recent times, do you think they know these are the same things in reverse? At least A/C is often used in sunny locales were solar can be used effectively.

AC is more than 100% efficient in heating the environment. This is unfortunate, but thermodynamics will win in the long run. Heat pumps are more than 100% efficient at heating the house, which is what we want, and one of the places where we are on the same side as thermodynamics.

AC is also more than 100% efficient at cooling the interior too.

And the Delta(T) that an AC has to work with are far more favorable in AZ summers than a heating heatpump in MI's upper peninsula in the winter.

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