4 ms·

Maybe you don't, but most people care---a lot---about the temperature of their dwelling (yes, to the resolution of a degree or so). And your friendly neighborh

Maybe you don't, but most people care---a lot---about the temperature of their dwelling (yes, to the resolution of a degree or so). And your friendly neighborhood microbiologist will be happy to discuss the implications of fridge temperature irregularity.

ocschwar 9y ago
And your friendly neighborhood electrical engineer will insist on having that discussion before finalizing a design for a fridge controller. Yes, it's important o keep a fridge in certain temperature bands. But there;s a lot of timing leeway in those bands, and it's exploitable as a form of energy storage.
- hinkley 9y ago
  I have a five year old fridge whose defining features include a compressor that runs pretty much all the time at a lower current draw to reduce overall energy use (and keep it quieter). An electrical engineer I believe designed that part of the system...
deleted 9y ago
[deleted]
greglindahl 9y ago
I don't think the microbiologist will object if the fridge is too cold for part of the day... it's not like we're storing the microbiologist's cell cultures.
- angry_octet 9y ago
  We already waste a great deal of food. Having it too cold will damage food, as will too hot. Older fridges used a sawtooth cooling pattern (on/off) but newer ones, with fancier motors, have might tighter regulation. I'm sceptical of how much energy can be scavenged. I'm sure with enough IoT you could delay motor start +/-30s across a region to smooth the tip of a load spike, but it sounds very complicated. How would end users be compensated for such a tiny shift in load? Isn't instaneous power demand a martingale process? It sounds like it would be easier and cheaper to have a few batteries.
  - greglindahl 9y ago
    I wasn't suggesting making it so cold as to damage food. I also wasn't arguing against batteries.
    - angry_octet 9y ago
      I was just generally arguing against the parent proposition as well.
      - greglindahl 9y ago
        Well, if you're a skeptic as to how much can be saved, you might want to look at the many "smart grid" studies, because this has been a hot topic for a while and is already implemented to a small degree.
    - PeterisP 9y ago
      If you were suggesting a refrigerator to run the cooling in the night so much so that it'd be able to sustain a safe temperature for many hours while conserving energy in the day, then yes, you were suggesting making it so cold as to damage food - a few degrees difference isn't sufficient to achieve what you want, and if your temperature fluctuates more than 3-4 degrees then the food either gets unsafely warm or gets frozen/damaged.
      - greglindahl 9y ago
        I wasn't suggesting that, no.
chongli 9y ago
Both of these problems can be solved by shifting the energy storage into a medium other than air: refrigerant. Store the compressed refrigerant in an insulated tank and use as needed. It's no different in principle from storing hot water in an insulated tank. Shift the load off peak.
- alacombe 9y ago
  > Store the compressed refrigerant in an insulated tank and use as needed Congratulation, you just re-invented the wheel. Do you really fridge builder are that dumb ?
gfisher 9y ago
A lot of the power that a fridge consumes is related to the defrost of coils. I don't care when my fridge heats up the coils, so that would be an easy load shift for a fridge that would not change the interior temp one bit.

ocschwar 9y ago

And your friendly neighborhood electrical engineer will insist on having that discussion before finalizing a design for a fridge controller. Yes, it's important o keep a fridge in certain temperature bands. But there;s a lot of timing leeway in those bands, and it's exploitable as a form of energy storage.

hinkley 9y ago
I have a five year old fridge whose defining features include a compressor that runs pretty much all the time at a lower current draw to reduce overall energy use (and keep it quieter). An electrical engineer I believe designed that part of the system...

deleted 9y ago

[deleted]

greglindahl 9y ago

I don't think the microbiologist will object if the fridge is too cold for part of the day... it's not like we're storing the microbiologist's cell cultures.

angry_octet 9y ago
We already waste a great deal of food. Having it too cold will damage food, as will too hot. Older fridges used a sawtooth cooling pattern (on/off) but newer ones, with fancier motors, have might tighter regulation. I'm sceptical of how much energy can be scavenged. I'm sure with enough IoT you could delay motor start +/-30s across a region to smooth the tip of a load spike, but it sounds very complicated. How would end users be compensated for such a tiny shift in load? Isn't instaneous power demand a martingale process? It sounds like it would be easier and cheaper to have a few batteries.
- greglindahl 9y ago
  I wasn't suggesting making it so cold as to damage food. I also wasn't arguing against batteries.
  - angry_octet 9y ago
    I was just generally arguing against the parent proposition as well.
    - greglindahl 9y ago
      Well, if you're a skeptic as to how much can be saved, you might want to look at the many "smart grid" studies, because this has been a hot topic for a while and is already implemented to a small degree.
  - PeterisP 9y ago
    If you were suggesting a refrigerator to run the cooling in the night so much so that it'd be able to sustain a safe temperature for many hours while conserving energy in the day, then yes, you were suggesting making it so cold as to damage food - a few degrees difference isn't sufficient to achieve what you want, and if your temperature fluctuates more than 3-4 degrees then the food either gets unsafely warm or gets frozen/damaged.
    - greglindahl 9y ago
      I wasn't suggesting that, no.

chongli 9y ago

Both of these problems can be solved by shifting the energy storage into a medium other than air: refrigerant. Store the compressed refrigerant in an insulated tank and use as needed. It's no different in principle from storing hot water in an insulated tank. Shift the load off peak.

alacombe 9y ago
> Store the compressed refrigerant in an insulated tank and use as needed Congratulation, you just re-invented the wheel. Do you really fridge builder are that dumb ?

gfisher 9y ago

A lot of the power that a fridge consumes is related to the defrost of coils. I don't care when my fridge heats up the coils, so that would be an easy load shift for a fridge that would not change the interior temp one bit.