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Smart thermostats inadvertently strain electric power grids

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Re: Smart thermostats inadvertently strain electric power grids

#171

Post by jrs235 »

hachari wrote: post #165
jffry wrote: post #154

Earlier quoted context omitted.

I'm not OP but I live in Washington DC, where our summers are definitely hot and humid. I keep my apartment around 78F to 80F. I use a dehumidifier to keep relative humidity around 50-55%, which corresponds to a dew point of ~60F which is low enough to still feel comfortable instead of "sticky". On especially hot days, I will raise the setpoint higher, and use a small fan to circulate air around where I am spending t…

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.

Re: Smart thermostats inadvertently strain electric power grids

#172

Post by bluGill »

rsync wrote: post #140
tguvot wrote: post #64

Earlier quoted context omitted.

in reality it's hard (and probably expensive) to proactively cool house with AC during summer at hot/sunny regions. I live in a house with rather good insulation (the one mandated by code) in south bay, yet all the walls getting rather warm and even if you try to precool air with AC walls with bring temperature back quickly My solution was to install whole house fan which runs through the night when temperature drops…

Whole house fans are really great. It’s cheating, a bit, to live in a place that drops 20-40 F at night … but even if we didn’t, the ability to turn every open window into an air conditioner is a great trick.

I'm going to tear mine out. It helps a little, but it leaks so much conditioned air when not in use i'm convinced it is a negative overall.

Re: Smart thermostats inadvertently strain electric power grids

#173

Post by tguvot »

mulmen wrote: post #163
tguvot wrote: post #152

Earlier quoted context omitted.

>Do you have any actual numbers for what is up to code insulation in California? California is a very temperate climate. I wouldn't exactly expect their code to have the highest insulation requirements. R-15 for 2x4 or R-21 for 2x6. Not highest numbers in USA I guess and after you buy house that already "exists", it's expensive to change it. >I am keenly aware of how much thermal mass walls hold. My apartment is 3 ex…

> my room wall on the outside hits 170F i think That seems unbelievable! Is that a typo?

Nope. It's west facing stucco wall without shadow. It's on sun through most of the day. With IR camera i clocked it in range of 65C-75C multiple times (so it's maybe not 170, but 165. hate CF conversions in head) . I had inverter on this wall, and it simply died from overheating. Same wall on the inside get's to 30C or more if I don't run AC that blows on it. Wall is triple layer stucco over plywood, R13 fiberglass and then drywall.

Re: Smart thermostats inadvertently strain electric power grids

#174

Post by bluGill »

tguvot wrote: post #152
mrguyorama wrote: post #143

Earlier quoted context omitted.

Do you have any actual numbers for what is up to code insulation in California? California is a very temperate climate. I wouldn't exactly expect their code to have the highest insulation requirements. Also, building codes should be considered the minimum. I am keenly aware of how much thermal mass walls hold. My apartment is 3 external walls that are constructed pretty much only of a few inches of concrete, bare. Th…

>Do you have any actual numbers for what is up to code insulation in California? California is a very temperate climate. I wouldn't exactly expect their code to have the highest insulation requirements. R-15 for 2x4 or R-21 for 2x6. Not highest numbers in USA I guess and after you buy house that already "exists", it's expensive to change it. >I am keenly aware of how much thermal mass walls hold. My apartment is 3 ex…

2x4 walls are allowed at all? That surprises me, up in the north they haven't been legal for decades now. Well it is more you can't meet the rvalue with them, but still even cheap houses don't get them

Re: Smart thermostats inadvertently strain electric power grids

#175

Post by tguvot »

bluGill wrote: post #172
rsync wrote: post #140

Earlier quoted context omitted.

Whole house fans are really great. It’s cheating, a bit, to live in a place that drops 20-40 F at night … but even if we didn’t, the ability to turn every open window into an air conditioner is a great trick.

I'm going to tear mine out. It helps a little, but it leaks so much conditioned air when not in use i'm convinced it is a negative overall.

tear it out and put a new one. There are models from airscape that come with motorized dumper doors with insulation. When fan is off, it's sealed.

Re: Smart thermostats inadvertently strain electric power grids

#176

Post by mulmen »

tguvot wrote: post #173
mulmen wrote: post #163

Earlier quoted context omitted.

> my room wall on the outside hits 170F i think That seems unbelievable! Is that a typo?

Nope. It's west facing stucco wall without shadow. It's on sun through most of the day. With IR camera i clocked it in range of 65C-75C multiple times (so it's maybe not 170, but 165. hate C F conversions in head) . I had inverter on this wall, and it simply died from overheating. Same wall on the inside get's to 30C or more if I don't run AC that blows on it. Wall is triple layer stucco over plywood, R13 fiberglass…

That's amazing. Really shows the value of overhangs, breezeways, and trees.

Re: Smart thermostats inadvertently strain electric power grids

#177

Post by chamanbuga »

jandrese wrote: post #46
evanreichard wrote: post #11

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…

Nest has an energy saving feature that feels like it is trying to boil the frog. We normally keep the thermostat at 78F (~25.5C), but over the course of a couple of weeks it ticked it up to 79F, then 80, then 81, and now 82F (~28C). I had to go in and manually adjust the schedule to get it back to something reasonable.

Holy, while in Toronto I set the thermostat to 68 and complain if I see it cross into the 70s. Thanks to the wind tunnel I'm in, I'm able to turn off the AC every 2-3 days for 1-2 days. Conventional wisdom tells me this is more costly than just keep the AC running all the time at a stable temperature, but, I don't really care about the cost saving over personal preference.

Re: Smart thermostats inadvertently strain electric power grids

#178

Post by jffry »

hachari wrote: post #165
jffry wrote: post #154

Earlier quoted context omitted.

I'm not OP but I live in Washington DC, where our summers are definitely hot and humid. I keep my apartment around 78F to 80F. I use a dehumidifier to keep relative humidity around 50-55%, which corresponds to a dew point of ~60F which is low enough to still feel comfortable instead of "sticky". On especially hot days, I will raise the setpoint higher, and use a small fan to circulate air around where I am spending t…

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.

Re: Smart thermostats inadvertently strain electric power grids

#179

Post by Nextgrid »

kennywinker wrote: post #115
doubleunplussed wrote: post #108

Earlier quoted context omitted.

In the long run ACs are exactly 100% efficient at heating the environment. The extra heat is only temporarily displaced from the building being cooled, and will leak back in eventually.

There is heat generated by the system, and heat generated by the power generation used to power the system. It’s definitely not a neutral system - that’d be thermodynamically impossible ( increasing entropy without external energy)

If you power the AC with 100% solar shouldn’t there be no extra heat generated?

As in you’re merely absorbing some of the heat from the sun to then move existing heat around?

Frankly, even without solar power it wouldn’t generate “extra” heat directly over a long timescale, it would only accelerate the release of existing “heat” currently trapped in oil/gas/nuclear/etc.

Re: Smart thermostats inadvertently strain electric power grids

#180

Post by tguvot »

bluGill wrote: post #174
tguvot wrote: post #152

Earlier quoted context omitted.

>Do you have any actual numbers for what is up to code insulation in California? California is a very temperate climate. I wouldn't exactly expect their code to have the highest insulation requirements. R-15 for 2x4 or R-21 for 2x6. Not highest numbers in USA I guess and after you buy house that already "exists", it's expensive to change it. >I am keenly aware of how much thermal mass walls hold. My apartment is 3 ex…

2x4 walls are allowed at all? That surprises me, up in the north they haven't been legal for decades now. Well it is more you can't meet the rvalue with them, but still even cheap houses don't get them

no idea. Insulation levels are part of the code. It will be used at least for cases "deep remodels" when house is stripped down to skeleton
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