Author Topic: A possible way to keep your fridge cold in long term blackouts.  (Read 12508 times)

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Offline msuffidyTopic starter

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So where I live I have never seen a blackout in 17 years last longer than 2 hours. We are getting a lot of bad storms and I was just even considering the problem.

Originally I thought what may be actually the most 'efficient', like in terms of input to output power, would be to modify a fridge compressor so it could be fed from a belt. The belt would connect to some sort of rotating power source, like a bike, or windmill.

Then I was thinking the most normal and easy way to do it is to get a power bank of some sort with a 120V inverter.

In this video it seems to do most of the things you need.


So I have the following sort of questions.

1) Provided a fridge is not all the time, but is on some of the time, can you humanly input the same power as a fridge uses (different if not started warm)?
2) With 120V inverters are there power losses when appliances are idle or disconnected?

So in conclusion based on the fact it does not happen here and I don't have a lot of value in terms of loss in my fridge, I think I am just going to ignore the problem.
 

Offline bob91343

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #1 on: June 18, 2022, 02:42:38 am »
I have come to the same conclusion.
 

Offline Someone

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #2 on: June 18, 2022, 02:50:54 am »
1) Provided a fridge is not all the time, but is on some of the time, can you humanly input the same power as a fridge uses (different if not started warm)?
No
Typical residential fridge+freezer, 300-400kWh per year:
https://www.energyrating.gov.au/calculator

Most humans are unable to produce 100W continuously:
https://en.wikipedia.org/wiki/Human_power

1kWh/day at least 10 hours continuous human effort
 
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Offline Someone

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #3 on: June 18, 2022, 02:52:30 am »
So could that much energy be supplied by human power?  Yes, probably.
Please demonstrate this! You won't be able to.
 

Online antenna

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #4 on: June 18, 2022, 03:11:21 am »
Crosley Icyball
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #5 on: June 18, 2022, 03:18:12 am »
So that's coincidentally almost exactly 1kWh / day, which translates to 41.7 Watts per. hour average --
and I believe these are likely normal usage numbers involving opening / closing the unit often, adding new items to be refrigerated, making ice, things one could cut back on during a power outage.

On a typical leisurely workout I easily sustained more than 41W output according to my exercise bicycle so truly it could
be done even manually on a generator bicycle.
24 hours a day continuous activity? Again, feel free to demonstrate this, do make a video of you providing 1kWh a day. 99% of the population will fall over spectacularly.
 

Offline msuffidyTopic starter

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #6 on: June 18, 2022, 03:24:57 am »
It sounds for a typical fridge it is close. Maybe a smaller one could be used for critical things.
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #7 on: June 18, 2022, 03:48:19 am »
And of course one can buffer excess in a battery to avoid needing to be quite so continual.

24 hours a day continuous activity? Again, feel free to demonstrate this, do make a video of you providing 1kWh a day. 99% of the population will fall over spectacularly.
It doesn't matter how perfectly you can capture and level the energy, 1kWh per day is outside the range achievable by most people. Its off into performance athlete territory. One of the often reproduced graphs on the topic is included below with a 1kWh/day locus. Feel free to come up with some data points that do sit above that locus, they're all going to be high performance athletes in the 0.00... something percent.
 
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Offline sleemanj

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #8 on: June 18, 2022, 04:10:30 am »
Typical residential fridge+freezer, 300-400kWh per year:

Poster asked about a fridge, not fridge+freezer.

You can get standalone fridges that need half of that power easily.
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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #9 on: June 18, 2022, 04:38:45 am »
Typical residential fridge+freezer, 300-400kWh per year:
https://www.energyrating.gov.au/calculator
Poster asked about a fridge, not fridge+freezer.

You can get standalone fridges that need half of that power easily.
When consumer says fridge they almost always mean a 2 door fridge+freezer combination, hence the direct link to the data source which surprise surprise calls a 2 door fridge+freezer, a "fridge". You could take all sorts of obnoxious interpretations of "fridge" but even a leading efficiency fridge only domestic unit still needs 400Whr/day:
https://reg.energyrating.gov.au/comparator/
Unless you want to start walking this to a silly point like a tiny "cold" wine fridge/humidor.
 
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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #10 on: June 18, 2022, 04:48:13 am »
To be precise I don't really agree with your statement that it is necessarily outside the range achievable by most people, rather a more likely correct statement would be that it's well outside the range *achieved* by most people between their late-teen years and middle age.  Clearly it wouldn't be productive to consider "most people" numerically including infants, toddlers, octogenarians, et. al.

But "performance athlete" level endurance with moderate strength / power output anyway is precisely what we're mostly all genetically / biologically "equipped" to be able (biologically) to achieve (given suitable prerequisite fitness conditioning).

Nomadic physically active lifestyles, surviving harsh conditions without technology, struggling physically just to survive vs.
predation, starvation, migration, etc.   Consider what may have been a much more "average person" level of fitness 13ky-1My ago for a hominid vs. today.   So with regular exercise / effort I wouldn't be at all surprised if the "average" young/mid-adult could become fit to achieve / well exceed that output power for 12-18 hours anyway with sleep becoming a barrier past that.

It is after all an "endurance" level of power output so like running a marathon (which is routinely done by young and old even not-so-performance-athlete types) it's mostly about a baseline level of cardio fitness and then sheer willpower and routine.
Provide some data points, human endurance falls off a cliff very quickly. What someone can do for an hour or two cannot be extrapolated out to all day long. 1kWh/day is Tour de France level endurance, not something that is achievable by normal people. You might be able to train some percentage of the population to do this, but that's not the question (having done endurance sports with people who wanted to do it, I can tell you normal people fall over and collapse when pushed to do that level of performance).

From the graph you cited the required level of fitness to generate -- asymptotically -- an energy production rate meeting 1kWh/day
is actually under the curve of "NASA curve for healthy men" implying to me that normally healthy men should be able to do that for
say 55W/18h or maybe 41.7W average / 24 hours or some other power-time integral that meets the energy production rate.
That isn't seeming to say it is only achieved by uber-athletes, though being able to do that and still get sleep normally and carry that on beyond 24 hours is clearly challenging due more to the "down time" of sleep than the actual endurance level wattage needed.
The 1kWh/day locus is not under "NASA curve for healthy men" at any point, that is an extrapolation of amateur athletes from another data set and might meet it at the single day 24 hour endurance point (that doesn't include a repeat performance for ongoing power outage). So an amateur athlete might be able to do 1 day of that power level, and fall over collapsed at the end of that effort.

How much more wrong do you want to be?
 
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Offline sleemanj

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #11 on: June 18, 2022, 05:01:23 am »
When consumer says fridge they almost always mean a 2 door fridge+freezer combination


1.  This is EEVBlog, engineers should define things in specific terms.
2.  If I go to buy a fridge, I'm buying a fridge, not a fridge freezer, if I wanted a fridge freezer I would ask for a fridge freezer
3.  While fridges are less common these days, they are still readily available...
 
Harvey Norman, who I think you have in Australia also, sells a number of them...

130-238kWh Refrigerators

That's not to say that it's not a silly idea to directly run a fridge from a bicycle **directly**, it is an obviously silly idea, the consumption of a fridge is not constant, it needs a large amount of power for a short amount of time and the human is woefully under equipped to provide the peak demand.

However, riding a bike charging a battery bank and running the fridge from said battery bank, we are probably achievable, for the sake of argument let's take the 130kWh fridge, about 356 Watt hours a day requirement, let's assume you can comfortably produce on your bicycle 25W continuous, might be possible, especially if you have a couple of people swapping every hour or so.

Even on your own you only have to cycle for about 14 hours a day, leaving 8 hours for sleeping and a couple hours for limping around wishing you'd bought a solar panel or generator instead of macguyvering your Raleigh 10 speed.

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #12 on: June 18, 2022, 05:40:47 am »
When consumer says fridge they almost always mean a 2 door fridge+freezer combination
1.  This is EEVBlog, engineers should define things in specific terms.
Which is why I was explicit "fridge+freezer" and shared the data sources (unlike everyone else). If you want criticise or poke holes then why pick out the accurate and referenced posts?

If people want more data... typical domestic refrigeration per household in Australia was over 2kWhr/day:
https://renew.org.au/renew-magazine/efficient-homes/unravelling-home-energy-use-across-australia/
That lumps combined fridge+freezer units together as "refrigerators" with a separate category for freezer only. Fridge only is so unusual it doesn't make a mention. Original source of the data is difficult to find, but it looks like that was from an earlier revision of "Residential Baseline Study 2015".

Typical household food storage energy use does not overlap with the typical household human power capability. There is some small double corner case of endurance athletes + small/few/efficient appliances, but even then its still needing a ridiculous amount of time/effort dedicated to keeping food cool and doing little else.
 

Offline BrianHG

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #13 on: June 18, 2022, 06:06:04 am »
Example log of  usable power from a treadmill motor rigged to a stationary bike before I broke my lower back:

Code: [Select]
logs\BikeBrake_05-11-2011_20h16m09s.raw   1:10:09.3     76.15
logs\BikeBrake_05-13-2011_14h12m10s.raw   1:10:07.0     88.05
logs\BikeBrake_05-16-2011_11h31m29s.raw   1:10:10.3     94.37
logs\BikeBrake_05-19-2011_08h34m19s.raw   1:10:08.3     92.38
logs\BikeBrake_06-19-2011_15h28m41s.raw   1:10:13.9     99.89
logs\BikeBrake_06-20-2011_12h35m14s.raw   1:10:10.2     91.49
logs\BikeBrake_06-21-2011_11h06m35s.raw   1:12:44.0     99.88
logs\BikeBrake_06-22-2011_12h24m06s.raw   1:10:06.0     101.35
logs\BikeBrake_06-23-2011_10h46m00s.raw   1:10:11.3     100.46
logs\BikeBrake_06-30-2011_16h42m45s.raw   1:10:08.0     100.60
logs\BikeBrake_07-02-2011_13h44m35s.raw   1:10:13.6     97.37
logs\BikeBrake_07-04-2011_10h47m49s.raw   1:10:09.0     102.89
logs\BikeBrake_07-05-2011_11h44m08s.raw   1:10:10.0     104.29
logs\BikeBrake_07-10-2011_12h56m26s.raw   1:10:08.6     101.98
logs\BikeBrake_07-11-2011_16h36m57s.raw   1:10:12.9     97.06
logs\BikeBrake_07-18-2011_13h12m12s.raw   1:10:09.1     100.71
logs\BikeBrake_07-20-2011_14h00m53s.raw   1:10:12.4     100.42
logs\BikeBrake_07-24-2011_13h41m13s.raw   1:10:20.2     103.44
logs\BikeBrake_08-01-2011_15h37m30s.raw   1:10:10.9     100.62
logs\BikeBrake_08-03-2011_13h47m30s.raw   1:10:11.3     104.12
logs\BikeBrake_08-04-2011_18h02m08s.raw   1:10:15.8     95.95
logs\BikeBrake_08-09-2011_12h59m31s.raw   1:10:14.7     104.57
logs\BikeBrake_08-18-2011_14h22m33s.raw   1:10:14.3     97.13
logs\BikeBrake_08-20-2011_16h52m49s.raw   1:10:10.5     96.79
logs\BikeBrake_08-22-2011_16h52m24s.raw   1:10:11.0     95.79
logs\BikeBrake_08-23-2011_14h59m23s.raw   1:10:06.5     93.97
logs\BikeBrake_08-28-2011_18h03m05s.raw   1:10:13.7     95.18
logs\BikeBrake_09-06-2011_14h59m03s.raw   1:10:14.0     90.67
logs\BikeBrake_09-11-2011_16h45m30s.raw   1:10:16.3     94.06
logs\BikeBrake_09-16-2011_17h30m48s.raw   1:10:15.0     101.04
logs\BikeBrake_09-18-2011_18h15m57s.raw   1:10:16.3     96.54
logs\BikeBrake_10-06-2011_10h59m14s.raw   1:10:33.8     86.90
logs\BikeBrake_10-10-2011_14h31m06s.raw   1:10:23.4     96.37
logs\BikeBrake_10-11-2011_14h32m33s.raw   1:10:14.6     100.29
logs\BikeBrake_10-22-2011_21h05m47s.raw   1:10:13.6     87.47
logs\BikeBrake_10-26-2011_17h27m12s.raw   1:10:08.3     82.98
logs\BikeBrake_11-04-2011_19h48m32s.raw   1:10:11.0     83.67
logs\BikeBrake_11-19-2011_20h21m35s.raw   1:10:15.0     87.35
logs\BikeBrake_11-21-2011_20h29m18s.raw   1:10:13.9     88.13
logs\BikeBrake_12-05-2011_11h36m14s.raw   1:10:13.3     76.95
logs\BikeBrake_12-07-2011_09h22m58s.raw   1:10:14.6     87.37
logs\BikeBrake_12-16-2011_11h47m23s.raw   1:10:22.3     87.33
logs\BikeBrake_12-18-2011_21h37m56s.raw   1:10:46.6     71.83
logs\BikeBrake_12-19-2011_20h31m55s.raw   1:10:20.1     75.96
logs\BikeBrake_12-29-2011_01h30m36s.raw   1:10:14.6     70.85
logs\BikeBrake_12-29-2011_15h31m58s.raw   1:10:19.7     85.47
logs\BikeBrake_01-01-2012_18h24m41s.raw   1:10:11.5     82.06
logs\BikeBrake_01-02-2012_23h40m48s.raw   1:10:21.0     75.89
logs\BikeBrake_01-03-2012_14h48m30s.raw   1:10:08.2     89.10
logs\BikeBrake_01-06-2012_00h08m40s.raw   1:12:28.3     91.47
logs\BikeBrake_01-09-2012_13h01m36s.raw   1:10:08.7     88.87
logs\BikeBrake_01-11-2012_19h10m47s.raw   1:10:11.7     94.32
logs\BikeBrake_01-14-2012_04h15m45s.raw   1:10:08.2     82.67
logs\BikeBrake_01-15-2012_03h09m43s.raw   1:10:12.4     81.97
logs\BikeBrake_01-16-2012_14h10m47s.raw   1:10:13.3     92.30
logs\BikeBrake_01-18-2012_14h23m24s.raw   1:10:12.5     92.82
logs\BikeBrake_01-19-2012_16h36m15s.raw   1:10:11.2     94.84
logs\BikeBrake_01-24-2012_18h00m16s.raw   1:10:14.1     86.09
logs\BikeBrake_01-27-2012_21h35m06s.raw   1:10:13.1     80.81
logs\BikeBrake_01-28-2012_16h19m43s.raw   1:10:16.9     95.11
logs\BikeBrake_01-30-2012_15h49m53s.raw   1:10:11.4     93.37
logs\BikeBrake_01-31-2012_13h51m08s.raw   1:10:10.1     96.24
logs\BikeBrake_02-01-2012_16h09m28s.raw   1:10:09.7     93.08
logs\BikeBrake_02-04-2012_21h23m43s.raw   1:10:13.6     88.37
logs\BikeBrake_02-06-2012_19h30m21s.raw   1:13:33.4     94.25
logs\BikeBrake_02-07-2012_18h22m55s.raw   1:10:07.9     97.75
logs\BikeBrake_02-16-2012_20h55m57s.raw   1:10:16.5     91.16
logs\BikeBrake_02-18-2012_09h27m13s.raw   1:10:11.5     93.05
logs\BikeBrake_02-20-2012_03h36m49s.raw   1:10:14.2     87.21
logs\BikeBrake_02-22-2012_07h04m19s.raw   1:10:16.9     101.13
logs\BikeBrake_03-04-2012_09h29m26s.raw   1:10:14.8     90.05
logs\BikeBrake_03-08-2012_14h48m36s.raw   1:10:12.0     91.71
logs\BikeBrake_03-09-2012_13h29m48s.raw   1:10:10.3     91.68
logs\BikeBrake_03-11-2012_13h28m52s.raw   1:11:03.5     93.60
logs\BikeBrake_03-14-2012_11h28m55s.raw   1:10:10.4     95.04
logs\BikeBrake_03-20-2012_14h26m45s.raw   1:10:08.5     90.43
logs\BikeBrake_03-22-2012_17h51m00s.raw   1:10:13.6     80.35
logs\BikeBrake_03-26-2012_11h08m58s.raw   1:10:09.1     92.26
logs\BikeBrake_04-01-2012_12h51m17s.raw   1:11:52.7     93.29
logs\BikeBrake_04-08-2012_12h49m27s.raw   1:10:11.8     96.27
logs\BikeBrake_04-09-2012_12h56m02s.raw   1:10:23.2     96.09
logs\BikeBrake_04-10-2012_14h00m14s.raw   1:09:43.7     89.43
logs\BikeBrake_04-13-2012_12h09m35s.raw   1:10:07.4     91.89
logs\BikeBrake_04-18-2012_16h30m32s.raw   1:10:12.3     98.31
logs\BikeBrake_04-22-2012_02h17m41s.raw   1:10:25.1     91.99
logs\BikeBrake_04-24-2012_16h13m45s.raw   1:10:08.8     93.04
logs\BikeBrake_04-28-2012_14h41m58s.raw   1:10:31.0     86.68
logs\BikeBrake_05-01-2012_13h21m44s.raw   1:26:09.8     102.90
logs\BikeBrake_05-03-2012_14h12m54s.raw   1:26:14.1     102.70
logs\BikeBrake_05-06-2012_09h04m57s.raw   1:26:17.1     103.71
logs\BikeBrake_05-07-2012_08h05m04s.raw   1:26:17.0     102.40
logs\BikeBrake_05-09-2012_19h12m18s.raw   1:10:14.4     84.59
logs\BikeBrake_05-12-2012_11h53m24s.raw   1:42:08.4     122.16
logs\BikeBrake_05-15-2012_11h20m21s.raw   1:42:18.3     125.05
logs\BikeBrake_05-19-2012_17h51m19s.raw   1:10:14.0     79.32



Format: date of workout - time when workout began - length of workout (includes 10 min warmup) - total surplus power sent into halogen bulbs over the time period.

After friction, belt, poor efficiency of using the treadmill motor at too low an RPM and as a generator, I'm guessing I was applying approximately double the wattage at the pedals.

Time to get modern power-meter pedals, mount them on my exercise bike to see how truly efficient my generator setup is so that I can see how well I actually performed.
« Last Edit: June 18, 2022, 06:11:12 am by BrianHG »
 

Offline BrianHG

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #14 on: June 18, 2022, 06:33:13 am »
I've a .png (graph color shows software gears, white = watts, green = pedaling rpm) of a workout graphs from my bike hardware and an old image of my bike hardware before I created the solid state control electronics.

The exercise micro-v-groove belt made the entire system silent.  In that image, the transformer was a resistor.  The electronics which generated the workout graphs removed the old transformer / switches for full PC with PWM control for software gearing and logging.
« Last Edit: June 18, 2022, 07:08:59 am by BrianHG »
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #15 on: June 18, 2022, 06:37:18 am »
I think it depends on the particulars.
For instance as the poster is flying a Canadian flag I might assume they're in Canada and not Belize, so the *actual* energy required could be quite different.
You bring up a huge volume of "but but but" and it all falls flat:
"Energy Consumption of Major Household Appliances Shipped in Canada" data up to 2018 shows "standard sized" "refrigerators" are over 1kWh/day except for the smallest category: https://oee.nrcan.gc.ca/corporate/statistics/neud/dpa/menus/aham/2014/tables.cfm

Even 2 fit adults will be flat out or unable to meet that level of power demand. As I said, people powering food cooling is a corner case convergence of very fit people in the household and a small/efficient fridge simultaneously. Even that optimistic case only just gets there with little time/energy to do anything else. You can't just keep chipping away at the edges to suddenly make the basic premise true, you're hunting some bizarre outlier that is not representative of the population. This isn't even a close run thing, its plainly impractical.
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #16 on: June 18, 2022, 06:48:05 am »
After friction, belt, poor efficiency of using the treadmill motor at too low an RPM and as a generator, I'm guessing I was applying approximately double the wattage at the pedals.

Time to get modern power-meter pedals, mount them on my exercise bike to see how truly efficient my generator setup is so that I can see how well I actually performed.
Thanks for the picture, 50% efficiency from that is probably a pessimistic figure. Belt drive to a small (DC permanent magnet?) motor/generator like that is probably around 70% or more.
 

Offline BrianHG

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #17 on: June 18, 2022, 06:58:18 am »
Those box-style fridges or deep-freezers where the door is at the top and open vertically use around half of the energy for freezing, around 1/3rd for refrigeration compared to the normal ones we use in our kitchens.  This has to do with the quality of the perfect unbroken insulation with the seal only around the top as these fridges were designed specifically for long term storage, low power consumption.

So, with a really efficiency  bike/generator combo, a LifePO battery pack as your capacitor, and a comfortable just around 100watt pedaling, you might get away with 2 adults willing to sacrifice around 3-4 hours a day each, that is unless you are both Tour-de-France grade riders who can sustain 400 watts for 1 hour straight.

Note that if you never open the fridge or add new food, maybe it will require a little less power.
 

Offline BrianHG

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #18 on: June 18, 2022, 07:03:00 am »
Belt drive to a small (DC permanent magnet?) motor/generator like that is probably around 70% or more.

I was running a 125v motor generating  15v at around 6 amps of current, around 10% of the designed RPM.  And if you look at permanent magnet DC generators, at low RPM, their efficiency drops off an edge like a cliff.  I would need to pedal at 5x my usually speed to get anywhere near the 70% efficiency, 10x to be in the motor's designed spec.  At proper RPM, voltage and current, the theory is around 83% efficient for a tuned DC brushed motor.

I needed another layer of gearing to achieve any good efficiency.

However, power-meter pedals would tell me the truth, except they are pricey for some good ones with the combination of having to buy biking shoes.
« Last Edit: June 18, 2022, 07:06:55 am by BrianHG »
 
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Offline Someone

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #19 on: June 18, 2022, 07:49:51 am »
You seem to be arguing for the sake of argument to try to prove me wrong or something which is odd since it was only as an theoretical aside that I (and presumably the original poster) mentioned the possibility (not practicability or desirability) of human power.
In the face of quality referenced figures, you keep posting up easily proven incorrect statements. Just because some of (your overly longwinded and dithering) posts contain some things that are true, you're still majority plainly wrong and digging in on them.

Do continue to walk this off to some imaginary place where endurance athletes are suddenly equipping their houses with speciality food cooling equipment for the purpose of emergency situations.....  except anyone with any sense would be getting a gas powered fridge for that, as already hinted at:
Crosley Icyball
Humans produce very little power, but you keep trying to push that out and say my very carefully framed and referenced figures are wrong. They're not. You guess at the population having lower power consumption, make no effort to check, and in the face of actual figures for the actual location you questioned, go on arguing how you are still right (in some new and even less believable frame)
 

Offline tszaboo

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #20 on: June 18, 2022, 08:56:14 am »
The last thing you want to do in case of an extended blackout is start a workout that you are not prepared. That is a sure way to die of hearth attack while waiting for the overloaded ambulance to arrive.
Just have a 12 pack of canned chicken soup in the garage. Maybe some MRE. Some canned food. Few bottles of water. Something that can cover your preferred "time without services". For me it is a week.
Eat/drink the stuff that's about to expire and buy new. This is not rocket science.
 

Offline sleemanj

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #21 on: June 18, 2022, 09:43:50 am »
hearth attack

Got to be careful of hearths.

~~~
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Offline tooki

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #22 on: June 18, 2022, 11:45:44 am »
FWIW, one key to having a fridge keep cold when unpowered is to keep it full. The thermal capacity of the air in the fridge is minimal. So fill any spare space with bottles of beverages. Once they’ve cooled initially, they don’t need any extra energy to keep cold.

This also improves the energy efficiency of a fridge or freezer in everyday use, because the volume of cold air lost in everyday use is reduced. (So yeah, keep ice packs in your freezer if you tend to not store much.)
 
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Offline Refrigerator

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #23 on: June 18, 2022, 01:33:41 pm »
IIRC an old school synchronous fridge compressor is rated around 160W. An induction motor is more-less a constant speed motor so if you don't supply enough power it will slip/stall, so let's keep that in mind.
To make it work you would need an inverter, a pure sine one at that, and some kind of way to stabilize the energy you produce by pedaling with some kind of battery or capacitor bank.
Most good quality pure sine inverters are rated above 85% efficiency (i checked) so let's take 85% as our efficiency, assuming worst-case scenario given the unstable power production.
So the sine inverter would need 188W of power just to run the fridge.
Add the inefficiency of your generator setup and ask yourself can you really produce this amount of power by pedaling?
Also let's not forget that fridges don't run constantly, rather they run only when they need to, so if you connect to the compressor directly, your pedaling would directly affect the temperature inside the fridge.
You could also use some kind of energy storage solution (battery bank or whatever) to produce energy by pedaling now and let the fridge use it later, but then you would have to add the charge-discharge inefficiency on top.
Serious cyclists often measure the power they produce and you might be inclined to use these numbers for estimations but we have to keep in mind that cyclists have the benefit of airflow to cool them down and the ones that care about their performance tend to me more athletic.
Unlike the average Joe, who would be sweating their ass off while pedaling indoors just to keep their beer cold  :popcorn:
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Online Alex Eisenhut

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #24 on: June 18, 2022, 02:16:46 pm »
The best you can do is make sure the magnetic seals are clean, and keep a few jugs of ice in the freezer to transfer to the fridge in case of a long blackout.

Keeping the freezer full,as noted, is a good idea, and since I don't usually keep much frozen foodstuff I keep it filled with ice.
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Offline Alti

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #25 on: June 19, 2022, 11:27:55 am »
I can tell you that mass market products (like fridges) are optimized to the very last cent and keeping all parameters constant - it is unlikely you can improve anything here and extending robustness against blackouts without serious investment.

If you have some money - get a small gasoline generator.
I doubt you can reliably power fridge from PV because blackout can happen during lousy weather. So most likely a serious battery bank is a must here anyway.
If you have some space - you could use a chest freezer and convert it into a fridge (replace temp control). Chest freezers are much better insulated than freezers and do not flush cold air when opened. Not a very practical fridge but a cheap off-the-shelf solution.
The advice of keeping fridge full is also a possibility but this decreases useful internal volume and might not be very comfortable. So you need to buy a fridge that is bigger than your actual needs, which affects running cost. How much are you willing to spend for this comfort?
Then, external insulation. Well I do not know how much heat/cold is escaping through side walls and you won't be able to insulate back of it because there sits the condenser. Also, flushed cold air won't be saved, no matter how thick this wall insulation is.

Interesting problem with a lot of potential solutions but without precise definition of OP's goals (in terms of devoted time, money, space, etc) it is hard to point into the right direction.

 
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Offline SeanB

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #26 on: June 19, 2022, 11:49:34 am »
Extra insulation is hard, because most units these days use the steel case as condenser, with steel coils glued to the steel sheet, held down with tape, before the insulation is foamed in place. Thus no coil on the back, and the interior coils are the same, placed on the plastic case to cool that way. no way to insulate, though the first run of the hot gas out of the compressor does run around the door frame, so that the seals do not freeze onto the metal. Best is to not open during power failures, and for longer use a chest freezer is good, and many also have enough control range to act as a fridge as well. Yes the fill with ice works, a lot of energy stored in that phase change.. BVut for longer than 8 hours you probably want a generator, or inverter and battery, charged from some source, solar, generator or even that pedal bike, just needs to have enough energy put in to run the compressor for an hour a day.

Tip for the freezer is to take a small plastic bottle, fill with water half way, and freeze. Then remove, open, and place a coin on top of the ice, close, and place back inside. That will tell you that, since you last looked at it, that there was a power failure long enough for the ice to melt, as the coin will be in the ice, and not on top.
 
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Offline tooki

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #27 on: June 19, 2022, 12:42:34 pm »
The advice of keeping fridge full is also a possibility but this decreases useful internal volume and might not be very comfortable. So you need to buy a fridge that is bigger than your actual needs, which affects running cost. How much are you willing to spend for this comfort?
No, the idea is to keep full any empty space in your fridge, not to get a bigger fridge! The point is to not have extra air. If it’s full of actual food and drinks, that’s fine. You only add extra bottles if your fridge has unused space. If you need the space, take them out.
 
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Online antenna

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #28 on: June 19, 2022, 07:10:10 pm »
Tip for the freezer is to take a small plastic bottle, fill with water half way, and freeze. Then remove, open, and place a coin on top of the ice, close, and place back inside. That will tell you that, since you last looked at it, that there was a power failure long enough for the ice to melt, as the coin will be in the ice, and not on top.
You can save that coin for laundry and just put an ice cube on the rack or in a bag.  If it is a frozen puddle on the bottom of the freezer or otherwise no longer shaped like a cube, there you go...  This is one of those simple problems people always over-engineer a solution for...
 
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Offline Siwastaja

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #29 on: June 19, 2022, 07:23:52 pm »
* Keep the fridge full
* Add extra insulation around the walls and the door.
   * Be careful not to insulate the condenser coils
   * Condensation of water can occur. The outer envelope of the newly added insulation should optimally be vapor tight.
* Avoid opening the fridge as much as you can during the emergency. Do bookkeeping so you know what you have without looking. Plan ahead and get everything out at once once or twice a day.

Maybe doing all that you could reduce the consumption by 30-40% It won't still be practical to be human-powered, but at least a smaller battery pack or PV panel will do.

But all hope is not lost: during coldest and darkest wintertime, you won't get much PV, but you could store foods outside.

During hot seasons, you definitely have enough sunlight to easily power the fridge, even during cloudy days.

So PV + battery + inverter, it is.
 

Offline SiliconWizard

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #30 on: June 19, 2022, 11:05:43 pm »
Many people do not realize that their average amount of power consumption is easily an order of magnitude more than what they could generate themselves with their body (and with great effort) - and depending on your activities and lifestyle, that could be more like 2 orders of magnitude.

 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #31 on: June 19, 2022, 11:55:39 pm »
Just call it a small fridge and assume 1kwh per day energy consumption.  1kwh = 860421 calories.  Get eating!  Wait... the fridge is now empty, you ate it all on day 1.  Congratulations, you no longer need a refrigerator!!!  Problem solved!!!!!
« Last Edit: June 19, 2022, 11:57:24 pm by antenna »
 
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Offline Cerebus

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #32 on: June 20, 2022, 01:47:38 am »
I think people are underestimating the power output quite ordinary people are capable of. Here's a chart of the brake power I could output a while back. Note my age on the chart, this isn't a fit young athlete but a very average healthy man in late middle age - no superman me, that's for sure. It's an interval session, so there are high peak power outputs, but the ~100W baseline is cruising speed, a warm up before, and gentle relaxation between the intervals. I could keep up that ~100W pace for several hours - I've certainly done it for at least 4 hours in a day. I'll emphasise that this is measured brake power, i.e. physical power available to drive a generator or machinery with the cycle inefficiencies already accounted for. Mean brake power across the whole session is 114W.

Sure, the 400Wh/day I could generate isn't enough power to run a typical domestic fridge but it shows that we're a lot closer than some people posit. If this old git can manage it then pretty much anyone who's not in poor health can.


Created on an instrumented cycle ergometer.
« Last Edit: June 20, 2022, 01:49:56 am by Cerebus »
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 
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Offline Cerebus

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #33 on: June 20, 2022, 01:59:53 am »
Just call it a small fridge and assume 1kwh per day energy consumption.  1kwh = 860421 calories.  Get eating!  Wait... the fridge is now empty, you ate it all on day 1.  Congratulations, you no longer need a refrigerator!!!  Problem solved!!!!!

Yeah, but the 'calories' used for food are actually kilocalories, so that 860421 calories is a 860 kcal meal - there's 770 kcals in a Big Mac and fries.

I'm cheating a little here, people are around 20% efficient. So that's about 4300 kcals, just under eight Big Macs (no fries). A 70 kg adult male would need another 1700 kcals/day just to support their basal metabolic rate.
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 
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Offline Zero999

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #34 on: June 20, 2022, 01:06:09 pm »
Just call it a small fridge and assume 1kwh per day energy consumption.  1kwh = 860421 calories.  Get eating!  Wait... the fridge is now empty, you ate it all on day 1.  Congratulations, you no longer need a refrigerator!!!  Problem solved!!!!!

Yeah, but the 'calories' used for food are actually kilocalories, so that 860421 calories is a 860 kcal meal - there's 770 kcals in a Big Mac and fries.

I'm cheating a little here, people are around 20% efficient. So that's about 4300 kcals, just under eight Big Macs (no fries). A 70 kg adult male would need another 1700 kcals/day just to support their basal metabolic rate.
The energy requirements for very active men i.e. on an polar expedition is around 6000 kcal/day.

No doubt it's possible to human power a refrigerator. If the control system is redesigned and the compressor is put on a variable speed drive, I'd imagine the efficiency would be higher, not lower. It's obviously impractical though. To avoid malnutrition and dehydration you'd need to eat a lot of food an drink more, so it would make more sense to just have more tins and dry food, which doesn't require refrigeration.
 

Offline Seekonk

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #35 on: June 20, 2022, 07:46:10 pm »
I read a lot of posts about how people prepare for the grid going down. I live 5 months of the year at my summer home in the northeast and my grid is always down, there is no electric. It is actually surprisingly cheap to live quite well off solar if you have engineering experience.  I have two water heaters, one just for the laundry, washing machine, dishwasher, fridge, pump and everything runs on a micro from PV. All loads are prioritized. Even a couple things that keep me alive at night. And all that runs on a car battery which has to have a near full charge as evening rolls around. The fridge only runs when the sun shines and if the charge drops 5% it will shut off.  The battery is just there for starting and I store all the "cold" I can till it gets down to 35F. I take up dead space with liquids. I don't have spoiled food and amazingly reliable thru rain and clouds. It is a dirt cheap system if you have programming skills. And why spend money on a system that will be used only once in a while. The battery can be from your extra car, boat, or garden tractor. Those solar $500 worth of panels can be heating water when there is no emergency. The payoff is just as good as a heat pump water heater.
 
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Offline BrianHG

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #36 on: June 20, 2022, 08:52:33 pm »
Just a power output example....
If only the sprinter could maintain that wattage for 12 minutes...


 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #37 on: June 20, 2022, 09:53:36 pm »
Just a power output example....
If only the sprinter could maintain that wattage for 12 minutes...
Which is the point I brought up that everyone seems to be trying to work around. Human power output vs duration is well known, the whole "I did XXX for YY minutes/seconds, and am sure I could do that all day long" is just wrong. The human body is layers and layers of squishy dynamic systems, unique to each person, each having their own endurance limitations. Your legs feel ok? no use when your brain is starved for energy.
 

Offline james_s

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #38 on: June 20, 2022, 09:54:28 pm »
My refrigerator consumes about 130W steady state once the compressor has been going for a bit and things are settled in after starting at about 75W. The duty cycle is pretty close to 50% so let's say the average continuous power is about 65W. From my own experience, I can generate around 100W on a stationary bicycle but only when I'm peddling flat out and I can only sustain that for maybe 20 seconds. Someone who is more physically fit than me could probably sustain 65W continuously for a few hours but it's going to require several people working in shifts to keep the fridge cold. Seems like a small gasoline, propane, natural gas or diesel generator is a lot more practical. A modest solar installation could also work well here, maybe 300-400W of panels and several deep cycle batteries.
 

Offline Zero999

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #39 on: June 20, 2022, 09:59:01 pm »
My refrigerator consumes about 130W steady state once the compressor has been going for a bit and things are settled in after starting at about 75W. The duty cycle is pretty close to 50% so let's say the average continuous power is about 65W.
How hot is your kitchen? That sounds like a very high duty cycle. It sounds like the gas is running out. My fridge probably has a duty cycle of under 10%, but I haven't measured it.
 

Offline james_s

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #40 on: June 20, 2022, 10:04:57 pm »
My refrigerator consumes about 130W steady state once the compressor has been going for a bit and things are settled in after starting at about 75W. The duty cycle is pretty close to 50% so let's say the average continuous power is about 65W.
How hot is your kitchen? That sounds like a very high duty cycle. It sounds like the gas is running out. My fridge probably has a duty cycle of under 10%, but I haven't measured it.

Typically about 69F, and the fridge has always run about the same since I bought it ~22 years ago. Keep in mind that US refrigerators are considerably larger than those in UK/Europe and technology has also improved in the time since mine was made. It also varies widely depending on the design, mine uses R134a refrigerant, others using different gasses may be optimized for different duty cycles.
 

Offline BrianHG

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #41 on: June 20, 2022, 10:43:19 pm »
If the power has gone out an an hour later you begin pedaling, that duty cycle may be broken and you may need to keep the compressor going for 100% of the time for an hour before the 10% duty cycle comes back.

Battery backup + solar + bike for extra supplemental battery charging may be achievable, but you would need to engineer the bike for an optimum pedaling pace, torque and wattage.  Without such research, you would be left with a devastating loss at the bike generator.

I have a 500watt continuous duty 3phase generator for sale.  You can easily run it at 1kw for 30 minutes, then allow a break for cooling.  It was designed for wind generation and has no cogging.  Short the leads on this baby and it will not turn as it is a neodymium super efficient generator.

See attached photos and data sheet.  If anyone wants it, I'll sell privately or put it up on ebay for 700$ us.
(Model number GL-PMG-500A, original shipping freight boxing)
Highly recommend that you can manufacture or machine the shaft to adapt a normal pulley.
« Last Edit: June 20, 2022, 10:46:53 pm by BrianHG »
 

Offline Cerebus

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #42 on: June 20, 2022, 10:50:53 pm »
From my own experience, I can generate around 100W on a stationary bicycle but only when I'm peddling flat out and I can only sustain that for maybe 20 seconds.

Not being funny, but if that's your maximum exercise capacity then, assuming that you don't have serious health problems that you didn't mention, you ought to talk to your doctor. 100W is a fairly normal cycling effort for someone just using a bike to get about for simple transportation. It's the equivalent of the standard 70kg man riding a heavy "sit up and beg" pushbike at 14 mph.

From https://www.okhane.com/calculators/cycling-wattage-calculator/:



Anybody got a syringe I can use to squeeze the magic smoke back into this?
 

Offline BrianHG

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #43 on: June 20, 2022, 10:52:01 pm »
With the above generator and proper gearing, with 6 Schottky diodes tied to a 24v or 48v LiFePO4 battery pack (one which contains internal balancing and protection), the more you sweat, the more current you will feed into the batteries.

Expect over 90% efficiency with that neodymium generator.
« Last Edit: June 20, 2022, 11:06:35 pm by BrianHG »
 

Offline james_s

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #44 on: June 20, 2022, 11:12:38 pm »
Not being funny, but if that's your maximum exercise capacity then, assuming that you don't have serious health problems that you didn't mention, you ought to talk to your doctor. 100W is a fairly normal cycling effort for someone just using a bike to get about for simple transportation. It's the equivalent of the standard 70kg man riding a heavy "sit up and beg" pushbike at 14 mph.


I was going off of the built in display on a stationary bicycle I used for a while, it's entirely possible that it was grossly inaccurate. I would rate my physical fitness as better than average for an American although I wouldn't go so far as to call myself athletic. At the time I was pretty regularly going on ~22 mile bike rides and now I walk briskly 1-2 miles every evening in my hilly neighborhood. I've hiked up to the ~5300 ft summit of Mt. Pilchuck quite a few times and did not find it particularly difficult.
 

Offline Cerebus

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #45 on: June 20, 2022, 11:23:50 pm »
Not being funny, but if that's your maximum exercise capacity then, assuming that you don't have serious health problems that you didn't mention, you ought to talk to your doctor. 100W is a fairly normal cycling effort for someone just using a bike to get about for simple transportation. It's the equivalent of the standard 70kg man riding a heavy "sit up and beg" pushbike at 14 mph.


I was going off of the built in display on a stationary bicycle I used for a while, it's entirely possible that it was grossly inaccurate. I would rate my physical fitness as better than average for an American although I wouldn't go so far as to call myself athletic. At the time I was pretty regularly going on ~22 mile bike rides and now I walk briskly 1-2 miles every evening in my hilly neighborhood. I've hiked up to the ~5300 ft summit of Mt. Pilchuck quite a few times and did not find it particularly difficult.

I think we can safely conclude then that the power display was, as we British engineers call it, "completely buggered".
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Offline BrianHG

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #46 on: June 21, 2022, 12:36:37 am »
This guy measures his chest freezer at 600 watts per day.
Figure less power per day to run it at refrigerator temperatures.

https://youtu.be/CGAhWgkKlHI?t=507



Seek to 8:30...

2 adults can reasonably pedal that with a good efficient generator wasting 1 hour each per day.
On my existing cheap bike, because of poor efficiency, make that 2 hours each per day, or 1 hour each, but sweating it out.
« Last Edit: June 21, 2022, 12:39:54 am by BrianHG »
 

Offline jonovid

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #47 on: June 21, 2022, 09:54:12 am »
to keep the refrigerator you need a lot of deep cycle battery 200AH or more. to feed the inverter & 400w of solar panels on a good day. IMO
better to use an internal combustion gen-set and keep frige door closed between 2hr runs every 6-8hrs.
a mod'ed elliptical trainer as gen-set is only good for 100w IF you can keep it up for more then an hr.  better ways to .
animals have better endurance if you can get your dog or horse on a treadmill. 
   
long term blackouts in a city?  if metropolitan boondocking the zombie apocalypse.
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Offline james_s

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #48 on: June 21, 2022, 05:14:58 pm »
I just use a Honda EU2000i, it runs all day on about a gallon of gasoline and at light load it drops down to a whisper quiet idle. I can power my whole house with it as long as I do a bit of load management and don't try to run two large loads at once.
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #49 on: June 22, 2022, 12:34:48 am »
How come so far, no mention of a bucket and a bag of salt (for the freezer) if winter storms are the primary concern?
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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #50 on: June 22, 2022, 02:20:58 am »
if you have a long power outage the best solution is to go to the gas station and buy a bag of ice and put that in the fridge
 

Offline msuffidyTopic starter

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #51 on: June 22, 2022, 04:47:41 am »
Well from this discussion it sounds like the following things can be observed,
1) It may help just to have a lot of stuff in your freezer depending on how long the blackout is.
2) It is preferable to gain energy from wind or solar.
3) Some freezers may require less overall power than fridges, so you are best to transfer all freezable things into one or have 2 at different temperatures, one more like a fridge. Or just keep them there in the first place.

It kind of sounds like those chest freezers are within the bike numbers though.
« Last Edit: June 22, 2022, 04:50:36 am by msuffidy »
 

Offline BrianHG

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #52 on: June 22, 2022, 05:21:02 am »
I think you can still add wind power to the list.
Also, if you live by a small creek or river, a water wheel can be great.  Even if it can only deliver a small 50 watts, 24 hours continuous is still 1.2kw per day.

Anyways, any solution you try, a LiFePO4 battery pack is still highly recommended to fill in the time when your power source isn't generating power + that extra day or so from when your power grid fails.
 

Offline Zero999

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #53 on: June 22, 2022, 06:01:43 am »
if you have a long power outage the best solution is to go to the gas station and buy a bag of ice and put that in the fridge
That's assuming they're open and aren't also out of power.
 

Offline Siwastaja

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #54 on: June 22, 2022, 06:52:26 pm »
You can also increase the efficiency (actually COP) of your fridge by replacing natural convection cooling of the condenser by forced (fan) cooling. Especially useful if you have the fridge installed so that there is this narrow gap where air goes in from bottom and out from above. Measure it; I find the whole space behind the fridge heats up by almost 10degC compared to ambient. More if you have dust accumulated. It's not too much to hinder operation, and it's considered normal. But still some room for optimization.

Add fan cooling and it's down to almost zero. You could expect this gives maybe 0.2-0.3 COP units in efficiency, and thus saving more than the fans consume, but of course use lowest power BLDC fans you can find (with good air volume / power consumption ratio). Wire the fans to only run together with the compressor, not all the time.

In addition to COP increase, it will also decrease heat flow through the back wall thanks to lower local ambient temperature there.

Drawer-type fridge (where all the cold air would not escape every time you open it) would be great. Personally, we have far too large fridge right now, very tall with no freezer (we have separate freezer). Because we don't need all the space, I have installed a simple thin XPS insulation board just behind the door, blocking the bottom part doorway when the fridge is opened, so that less cold air escapes.
« Last Edit: June 22, 2022, 06:55:00 pm by Siwastaja »
 

Offline Siwastaja

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #55 on: June 22, 2022, 06:57:33 pm »
Re using water bottles etc. to store thermal energy;

You could improve the storage a lot by utilizing phase change energy, by cleverly placing all the water bottles just near the evaporator, basically almost blocking it with the bottles. In such a way you can adjust the fridge "too cold", and they start freezing when you have power, but also have enough thermal impedance that your sensitive foodstuff like salads do not start to freeze. These half-frozen bottles would supply the cold for much much longer than just water bottles sitting at +3degC. Finding the right arrangement would require some testing, though.
 
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Online coppercone2

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #56 on: June 22, 2022, 09:39:51 pm »
if you have a long power outage the best solution is to go to the gas station and buy a bag of ice and put that in the fridge
That's assuming they're open and aren't also out of power.

Usually their not that wide spread unless some serious shit went down
 

Offline BrianHG

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #57 on: June 22, 2022, 10:14:39 pm »
if you have a long power outage the best solution is to go to the gas station and buy a bag of ice and put that in the fridge
That's assuming they're open and aren't also out of power.

Usually their not that wide spread unless some serious shit went down
Depends where you live.
You may be living in a small northern town who shares all their power from 1 sub-station.  Like what we call here the up-north from where I live in Montreal where we have our summer camps and weekend cottage houses.  When there is a power-failure, an entire small region goes out including the local town gas stations & convenience stores.
 

Offline Smokey

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #58 on: June 22, 2022, 11:11:36 pm »
<----- recreational road cyclist, with a power meter

If you want to know about the capabilities of the human body to put out consistent power, talk to the cyclists. 

https://www.trainerroad.com/blog/what-ftp-really-means-to-cyclists

When I was riding a few times a week, I got my FTP up to about 180W.  What that effectively means is that (given adequate nutrition) I could put out about 180W indefinitely.  Any more than that and you start the clock that leads to running out of juice and entering the deep dark pain cave.  I'm not bragging.  That is by no means great.  I got dropped all the time by other normal (non pro) people that could put out 200W+. 

So while I could do 180W, it took a really long time to get that fit AND I was working hard to keep up that power.  FTP is right on the edge of being really really uncomfortable.  Plus after doing that for any decent period of time you just want to get off the bike and eat all the food you can find.

So could you power a fridge with a cycle?  Maybe.  But after you got off the bike you will need to eat all the food in the fringe anyway.


Here is the table of power output for various levels of SERIOUS cyclists, all the way up to world class:
https://zwiftinsider.com/rider-categorization-based-on-ftp-how-do-you-rank/


And here is an entertaining video of a seriously strong cyclist trying to power a toaster:


 
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Offline james_s

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #59 on: June 22, 2022, 11:14:50 pm »
Back around 2007 we had one of those once a decade kind of winter storms come right after a period of unusually heavy rain. It knocked down hundreds of trees all over the area and those knocked out multiple large transmission lines carrying power into the region. Large areas were without power for days and it was actually a serious issue because while gas stations had plenty of fuel, they didn't have power to run the pumps or the transaction systems to sell it. I think a lot of them got generators after that, but for a few days it was a real challenge to find fuel and this is a heavily populated area around Seattle, not some little backwoods town. Doesn't happen often, in fact that's the only time in my lifetime I've seen it, but it can happen.
 

Offline james_s

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #60 on: June 22, 2022, 11:16:30 pm »
So could you power a fridge with a cycle?  Maybe.  But after you got off the bike you will need to eat all the food in the fringe anyway.

LOL!  :-DD
 

Offline BrianHG

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #61 on: June 23, 2022, 01:10:33 am »
So could you power a fridge with a cycle?  Maybe.  But after you got off the bike you will need to eat all the food in the fringe anyway.

Yes, when I worked out every second day, my food and water intake was almost double compared to when I do not exercise for 2 or more weeks.  On the rare occasion of working out everyday for 1 week, a good test of fitness for me, just my filet mignon consumption would jump to over a pound/day.  It literally cost me almost double in my personal grocery bill just to exercise.  And if this is not the case for you, then you are not pushing your body during workouts, or, you are just as active when you do not exercise.

Until I get power pedals to properly calibrate my old biking logs, based on my treadmill motor surplus wattage readings, I was probably outputting ~200 watts in an hour.
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #62 on: June 23, 2022, 01:23:37 am »
When I was riding a few times a week, I got my FTP up to about 180W.  What that effectively means is that (given adequate nutrition) I could put out about 180W indefinitely.  Any more than that and you start the clock that leads to running out of juice and entering the deep dark pain cave.
....
Here is the table of power output for various levels of SERIOUS cyclists, all the way up to world class:
https://zwiftinsider.com/rider-categorization-based-on-ftp-how-do-you-rank/
Its not infinite, an FTP figure (anaerobic threshold for the older crowd) is only part of the biological systems: muscle + cardiovascular mostly, balancing lactate production and clearing. This is one limiting factor of many, and others will catch up with most people. Humans just aren't great at sustained high effort. Like the posters before, if you think its possible for you to do such a sustained effort to reach 1kWh in a single push, then video it and show the world. You'll be picked up as a pro athlete overnight if thats done at 180W indefinitely.

Following that second link of yours through to some of the originating data at cyclinganalytics shows real measured results steadily dropping away beyond 1hr (attached below) with a plateau from 5min to 1hr just as the oft reproduced NASA data I posted on the first page. Endurance is much more complex than a single point and cant be readily extrapolated out as every person is different. I have/had high end sprinting <10min figures against the below graph, but do "poorly" in the 1 - 2 hour region, then return back to competitive at 12-18hr. Its not some simple curve, and very very very few people rise above the round figure of 1kWh/day, even 500-600Wh/day would leave the vast majority of people completely exhausted ("buggered" as the locals here would say).
 

Offline Geoff-AU

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #63 on: June 23, 2022, 04:40:04 am »
A couple of years ago we had a storm that brought down multiple trees and knocked out power for 4 days.

The neighbours immediately had a huge diesel generator delivered and it sat there chugging away for the duration.

We threw out a whole fridge of food.  Hot water lasted 3 days (summer, thankfully). But a house is bloody useless without ANY power.

Having since moved into our own home, some resiliency was on the cards.  When installing PV I selected an inverter - Fronius Gen24 - that has a "PV point".  When the grid goes down, the PV point activates and can deliver up to 3kW of available solar energy.  I figure if we end up having another huge outage, the fridge and the mobile phone charger gets plugged into the PV point and we can ride through the evenings without opening the fridge much.  It should survive at OK temperatures overnight.

Eventually when batteries are a bit more economic I'll install one and not even have to worry about swapping plugs over.
 
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Offline james_s

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #64 on: June 23, 2022, 04:46:30 pm »
A couple of years ago we had a storm that brought down multiple trees and knocked out power for 4 days.

The neighbours immediately had a huge diesel generator delivered and it sat there chugging away for the duration.

We threw out a whole fridge of food.  Hot water lasted 3 days (summer, thankfully). But a house is bloody useless without ANY power.

Did you try asking if you could run an extension cord over to their house to power your fridge and run a few lights? Certainly I would oblige if one of my neighbors made the request and my generator had sufficient capacity to accommodate.
 

Offline Mr. Scram

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #65 on: June 23, 2022, 05:05:44 pm »
Having solar panels and one of those powerwall house batteries would probably work. Modern fridges aren't that power hungry. I don't think the technology is quite ready to go entirely off-grid, but it does reduce your dependence on external infrastructure a lot.
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #66 on: June 23, 2022, 05:39:21 pm »
Many people do not realize that their average amount of power consumption is easily an order of magnitude more than what they could generate themselves with their body (and with great effort) - and depending on your activities and lifestyle, that could be more like 2 orders of magnitude.
Most people also don't realize how much energy we consume to move ourselves in 1-2 ton metal cans with rubber wheels attached to them. A colleague did a survey asking the average joe how long an electric car can power your house. Take an average modern 60kWh EV and an average household (here in NL a family household will take say 3000kWh/year). Most people responded with guesses of a couple to several hours.

But if you do some rough numbers.. round up to 3650kWh per year, 60kWh car, that's 6 days. If you're a bit more energy conscious or get a bigger Tesla EV you can easily stretch that to 2 weeks.
Or.. you can drive that car from 100% to 0% SOC in the couple of hours people were guessing!

I read a lot of posts about how people prepare for the grid going down. I live 5 months of the year at my summer home in the northeast and my grid is always down, there is no electric. It is actually surprisingly cheap to live quite well off solar if you have engineering experience.  I have two water heaters, one just for the laundry, washing machine, dishwasher, fridge, pump and everything runs on a micro from PV. All loads are prioritized. Even a couple things that keep me alive at night. And all that runs on a car battery which has to have a near full charge as evening rolls around. The fridge only runs when the sun shines and if the charge drops 5% it will shut off.  The battery is just there for starting and I store all the "cold" I can till it gets down to 35F. I take up dead space with liquids. I don't have spoiled food and amazingly reliable thru rain and clouds. It is a dirt cheap system if you have programming skills. And why spend money on a system that will be used only once in a while. The battery can be from your extra car, boat, or garden tractor. Those solar $500 worth of panels can be heating water when there is no emergency. The payoff is just as good as a heat pump water heater.
People that refit a camper van to a tiny house or their vacation home on wheels, have similar systems. They may put a few solar panels on the roof, install a few batteries (even old fashioned lead-acid ones), a few inverters and they're off the grid. If you run a small laptop, a small fridge or cool box and some 5W LEDs, you can go quite far.

From my own experience, I can generate around 100W on a stationary bicycle but only when I'm peddling flat out and I can only sustain that for maybe 20 seconds.

Not being funny, but if that's your maximum exercise capacity then, assuming that you don't have serious health problems that you didn't mention, you ought to talk to your doctor. 100W is a fairly normal cycling effort for someone just using a bike to get about for simple transportation. It's the equivalent of the standard 70kg man riding a heavy "sit up and beg" pushbike at 14 mph.

From https://www.okhane.com/calculators/cycling-wattage-calculator/:
I agree. For someone like myself who is totally out of shape due tendon issues and whatnot, but luckily no cardiovascular issues, can do around 100W 'continuous' (30min span) on a home trainer. Peak power is 400W+ on home trainer. Using that site, it matches quite well with a bike sprint I did the other day. I got home from work and decided to see if I could (still) match speed of regular 50km/h car traffic. I could for a good half minute or so. I guess I was doing 40km/h or so. That website calculates ~500W output. I'm in my early 30s but also hugely overweight, although luckily that last detail doesn't matter a ton (pun intended) in cycling.
Oh and cycling outdoors with that speed is much nicer than indoors. With this weather (30C+) I wouldn't even want to think about doing any activity without some kind of cooling!
 

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Offline BrianHG

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #68 on: June 23, 2022, 07:07:02 pm »
https://zwiftinsider.com/wp-content/uploads/2016/01/ftp-table.png
Those tables are watts per kilogram.  Not too useful.  Even in the untrained portion at the bottom, if I were untrained and 250kg of fat, believe me, I will not generate ~580 watts in 5 minutes.  I would be dead of a heart attack attempting that pace within seconds.
 
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Offline Kerlin

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #69 on: June 23, 2022, 07:49:21 pm »
A couple of years ago we had a storm that brought down multiple trees and knocked out power for 4 days.

The neighbours immediately had a huge diesel generator delivered and it sat there chugging away for the duration.

We threw out a whole fridge of food.  Hot water lasted 3 days (summer, thankfully). But a house is bloody useless without ANY power.

Did you try asking if you could run an extension cord over to their house to power your fridge and run a few lights? Certainly I would oblige if one of my neighbors made the request and my generator had sufficient capacity to accommodate.


Doh!
Of course the whole area went out.

"A couple of years ago    WE      had a storm that brought down multiple trees and knocked out power for 4 days"
                                   -----

The storm doesn't happen on one property, so he lost his too.


« Last Edit: June 23, 2022, 09:45:39 pm by Kerlin »
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Offline Kerlin

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #70 on: June 23, 2022, 08:24:11 pm »
I had had this happen too, possibly same storm, a lot who live in the Dandenongs did, the trees are huge.
On that occasion, as a solution, I put the food in an Esky (ice chest) and took it to an out of area friends place and drove to their place every day. Some couldn't leave the area due to giant trees across the road, I could.

I was considering how long you would need to run a fridge per day to keep frozen food from going off, not to keep it frozen, allow it to slowly thaw.
Then have a feast of the most expensive produce first say seafood, then meat then chicken. Then on the maybe the third or fourth day throw the rest of it out if need be.
I was thinking this could be done with a smaller bar fridge and a battery solar system. Which would allow the fridge to run for a while during the best power producing time, when the sun was up.
Build a processor controlled system to measure the temperature of the food and supervise it all.
The system could include only running a generator when needed as fuel was scarce. It also could be set up to notify when the food was getting a bit off.
Then monitor and modify the program it while it was running, being an electronics dude that would provide entertainment while the power was out.
Point is then it doesn't need to be run for the whole day.
Wouldn't require so much power capacity and fuel, may help avoid the main cost of throwing some food out, a partial solution.
Anyway that time was so bad the giant trees many cut many houses in half, might crash through the solar and whole system.

Forget the pedaling and fitness argument, its going no where eh?

« Last Edit: June 23, 2022, 10:02:08 pm by Kerlin »
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Online langwadt

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #71 on: June 23, 2022, 08:28:23 pm »
https://zwiftinsider.com/wp-content/uploads/2016/01/ftp-table.png
Those tables are watts per kilogram.  Not too useful.  Even in the untrained portion at the bottom, if I were untrained and 250kg of fat, believe me, I will not generate ~580 watts in 5 minutes.  I would be dead of a heart attack attempting that pace within seconds.

it is perfectly useful for people of normal weight, 250kg is so far off normal that is totally irrelevant
 

Offline james_s

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #72 on: June 23, 2022, 09:55:54 pm »
A couple of years ago we had a storm that brought down multiple trees and knocked out power for 4 days.

The neighbours immediately had a huge diesel generator delivered and it sat there chugging away for the duration.

We threw out a whole fridge of food.  Hot water lasted 3 days (summer, thankfully). But a house is bloody useless without ANY power.

Did you try asking if you could run an extension cord over to their house to power your fridge and run a few lights? Certainly I would oblige if one of my neighbors made the request and my generator had sufficient capacity to accommodate.


Doh!
Of course the whole area went out.

"A couple of years ago    WE      had a storm that brought down multiple trees and knocked out power for 4 days"
                                   -----

The storm doesn't happen on one property, so he lost his too.


I guess you missed the part where he said his neighbor brought in a big diesel generator, and my comment that if my generator had sufficient capacity I would be happy to let the neighbor plug into it. Obviously my comment only makes sense if the neighbor has a generator or other backup power source.
 

Offline james_s

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #73 on: June 23, 2022, 10:14:08 pm »
No you said to the poster-

Did you try asking if you could run an extension cord over to their house to power your fridge and run a few lights? Certainly I would oblige if one of my neighbors made the request and my generator had sufficient capacity to accommodate.

  Did YOU try asking If  YOU   could run an extension cord over to   THEIR   house
       ----                       ----                                                          -------
                 

Are you having difficulty comprehending English? I don't understand what the confusion is here.

Someone said that during an extended power outage their neighbor brought in a large generator to power their (the neighbor's) house.

I asked the person whose neighbor had a generator if they had asked the neighbor if they (the poster her whose power was out) could run a cord over to the house with the generator to power their fridge and stuff.

This is a very simple thing, I thought. I have a backup generator and if my neighbor asked, I would be happy to let them run a cord over to my house to borrow some power from my generator, provided it had sufficient capacity.
 

Offline Kerlin

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #74 on: June 23, 2022, 10:14:58 pm »
  Did    YOU     try asking If   YOU   could run an extension cord over to   THEIR   house.
           ----                         ----                                                           -------

The neighbor had the generator not him, the neighbor is not here.
             
« Last Edit: June 23, 2022, 10:24:37 pm by Kerlin »
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Offline Someone

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #75 on: June 23, 2022, 10:28:58 pm »
https://zwiftinsider.com/wp-content/uploads/2016/01/ftp-table.png
Those tables are watts per kilogram.  Not too useful.  Even in the untrained portion at the bottom, if I were untrained and 250kg of fat, believe me, I will not generate ~580 watts in 5 minutes.  I would be dead of a heart attack attempting that pace within seconds.
it is perfectly useful for people of normal weight, 250kg is so far off normal that is totally irrelevant
There is nothing "normal" about those tables, they are about athletes who choose to do the activity, a self selecting minority of people. It is not applicable to the general population.
 
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Offline Cerebus

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #76 on: June 24, 2022, 12:50:33 am »
Did you try asking if you could run an extension cord over to their house to power your fridge and run a few lights? Certainly I would oblige if one of my neighbors made the request and my generator had sufficient capacity to accommodate.

Depends where in Aus Geoff is. Neighbour could be "Just next door" or could be "We're gonna need a really long extension cable". Aussies have caught me out before by talking about their neighbours and then later it becomes clear in the conversation that you need to drive if you're going to borrow a cup of sugar from them.
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 

Offline Cerebus

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #77 on: June 24, 2022, 01:04:08 am »
  Did    YOU     try asking If   YOU   could run an extension cord over to   THEIR   house.
           ----                         ----                                                           -------

The neighbor had the generator not him, the neighbor is not here.
             

I'm with James here, you seem to not be understanding quite simple English.

James to Geoff:  "Did you [Geoff] try asking if you [Geoff] could run an extension cord over to their [the neighbours]  house ..."

What's the issue with that?
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 
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Online tggzzz

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #78 on: June 24, 2022, 07:52:26 am »
Don't use bottles with plain water, because they will only keep the freezer contents at 0C. At that temperature some of the freezer contents will already have defrosted.

Do use "eutectic plates" available from catering suppliers, e.g. https://www.frigolab.eu/gb/127-eutectic-plates

You can choose the freeze/thaw temperature, so if you want to keep something below -14C, use a -18C plate and set the freezer to -21C.

If you are a cheapskate you can make them yourself: just add the desired amount of salt to water in a plastic bottle, then test it in the freezer.
There are lies, damned lies, statistics - and ADC/DAC specs.
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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #79 on: June 24, 2022, 08:04:46 am »
https://zwiftinsider.com/wp-content/uploads/2016/01/ftp-table.png
Those tables are watts per kilogram.  Not too useful.  Even in the untrained portion at the bottom, if I were untrained and 250kg of fat, believe me, I will not generate ~580 watts in 5 minutes.  I would be dead of a heart attack attempting that pace within seconds.

it is perfectly useful for people of normal weight, 250kg is so far off normal that is totally irrelevant

If the table is best calibrated at normal weight, e.g. BMI=20, then the table is better expressed in terms of a person's length. But perhaps a W/m^2 is a weird figure.
Anyhow, I think those tables are more accurate at the higher end. 2 Tour-de-France athletes of similar length will have a similar power output (say a +/-10% difference + a good day will win you a race). On the lower end of the scale, the stddev is much bigger, which this table doesn't capture as well. Some people may start at 80W, others can maybe do 150W. Also depends *a lot* on age.
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #80 on: June 24, 2022, 11:00:15 am »
https://zwiftinsider.com/wp-content/uploads/2016/01/ftp-table.png
Those tables are watts per kilogram.  Not too useful.  Even in the untrained portion at the bottom, if I were untrained and 250kg of fat, believe me, I will not generate ~580 watts in 5 minutes.  I would be dead of a heart attack attempting that pace within seconds.

Tables like this describe athlete types. Note that the lowest-tier rating on that table is "untrained (non-racer)". This means basically a self-trained non-professional person who is basically an athlete by hobby. 95% of people would fall completely outside of this table.

This is also why it works per kilogram; there's just this hidden assumption that anybody who gets on this table at all has very good muscle-to-fat ratio to begin with. If you totally exclude non-athlete types, then body mass is likely directly proportional to muscle power, even better than height is.
« Last Edit: June 24, 2022, 11:05:20 am by Siwastaja »
 
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Offline Siwastaja

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #81 on: June 24, 2022, 11:13:59 am »
I was thinking this could be done with a smaller bar fridge and a battery solar system. Which would allow the fridge to run for a while during the best power producing time, when the sun was up.
Build a processor controlled system to measure the temperature of the food and supervise it all.

PV panels are cheap; instead of buying a separate smaller fridge and juggling foodstuff between fridges, simplest is to get large enough PV system to keep your usual fridge, freezer and whatever other small loads running.

For example, my 3kWp rooftop system produces anything between 5kWh to nearly 20kWh a day, ignoring dark winter time. Some kind of worst-case super rainy day might go below 3kWh. Even this is three times the energy needed to run fridge+freezer.

A tiny (by modern standards) 1kWp PV system will be more than sufficient, and it is not much more expensive than some special "camper" installations made of small 150W panels.

But while at it, it would be a good idea to just buy decently sized PV system like 4-5kWp, then you would be part of solving the problem instead of just coping with it. But I don't know what is the current market situation with inverters that work both off-grid and grid-tied modes. Mine is grid-tie only which kind of sucks because it won't help me in case of emergency. Thankfully, grid is really fine here, and it is unlikely to radically change.
 
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Offline Cerebus

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #82 on: June 24, 2022, 01:11:08 pm »
https://zwiftinsider.com/wp-content/uploads/2016/01/ftp-table.png
Those tables are watts per kilogram.  Not too useful.  Even in the untrained portion at the bottom, if I were untrained and 250kg of fat, believe me, I will not generate ~580 watts in 5 minutes.  I would be dead of a heart attack attempting that pace within seconds.

Tables like this describe athlete types. Note that the lowest-tier rating on that table is "untrained (non-racer)". This means basically a self-trained non-professional person who is basically an athlete by hobby. 95% of people would fall completely outside of this table.

This is also why it works per kilogram; there's just this hidden assumption that anybody who gets on this table at all has very good muscle-to-fat ratio to begin with. If you totally exclude non-athlete types, then body mass is likely directly proportional to muscle power, even better than height is.

That might be a false set of assumptions. There's a lot of cross-over between exercise tolerance testing for medical/physiological research/diagnosis and data published for pure cycling/active-fitness purposes. The better tabulations published for cycling and fitness purposes draw their data from published physiology papers as well as narrower studies, and so encompass a much broader range of test subjects  than "cyclists who are interested enough to have undergone exercise tolerance testing" or "healthy 70kg males aged 21-25".
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 
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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #83 on: June 24, 2022, 09:20:00 pm »
https://zwiftinsider.com/wp-content/uploads/2016/01/ftp-table.png
Those tables are watts per kilogram.  Not too useful.  Even in the untrained portion at the bottom, if I were untrained and 250kg of fat, believe me, I will not generate ~580 watts in 5 minutes.  I would be dead of a heart attack attempting that pace within seconds.

Tables like this describe athlete types. Note that the lowest-tier rating on that table is "untrained (non-racer)". This means basically a self-trained non-professional person who is basically an athlete by hobby. 95% of people would fall completely outside of this table.

This is also why it works per kilogram; there's just this hidden assumption that anybody who gets on this table at all has very good muscle-to-fat ratio to begin with. If you totally exclude non-athlete types, then body mass is likely directly proportional to muscle power, even better than height is.

The most important reason that cyclist compare power with watts/kg is because they ride up hills.  Every kg you have to drag up a hill  needs more power to go the same speed in a race.  That's how you can compare the effective power output of a big dude and a small dude to see who would win a race.  But realistically, there are no pro BIG dudes.
Also it's largely irrelevant that they use w/kg for this discussion.  Just use a fixed weight for everything and you can focus on the differences between watts for the various levels, which is what we are after here. 
For reference, Chris Froome weighed about 69.9 kg.
https://en.wikipedia.org/wiki/Chris_Froome

 

Offline Cerebus

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #84 on: June 25, 2022, 12:46:36 am »
But realistically, there are no pro BIG dudes.

Not among pro road cyclists, but there are some monsters out there among the pro track cyclists.
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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #85 on: June 25, 2022, 12:59:15 pm »
https://zwiftinsider.com/wp-content/uploads/2016/01/ftp-table.png
Those tables are watts per kilogram.  Not too useful.  Even in the untrained portion at the bottom, if I were untrained and 250kg of fat, believe me, I will not generate ~580 watts in 5 minutes.  I would be dead of a heart attack attempting that pace within seconds.

Tables like this describe athlete types. Note that the lowest-tier rating on that table is "untrained (non-racer)". This means basically a self-trained non-professional person who is basically an athlete by hobby. 95% of people would fall completely outside of this table.

This is also why it works per kilogram; there's just this hidden assumption that anybody who gets on this table at all has very good muscle-to-fat ratio to begin with. If you totally exclude non-athlete types, then body mass is likely directly proportional to muscle power, even better than height is.

The most important reason that cyclist compare power with watts/kg is because they ride up hills.  Every kg you have to drag up a hill  needs more power to go the same speed in a race.  That's how you can compare the effective power output of a big dude and a small dude to see who would win a race.  But realistically, there are no pro BIG dudes.
Also it's largely irrelevant that they use w/kg for this discussion.  Just use a fixed weight for everything and you can focus on the differences between watts for the various levels, which is what we are after here. 
For reference, Chris Froome weighed about 69.9 kg.
https://en.wikipedia.org/wiki/Chris_Froome


https://www.topendsports.com/sport/cycling/anthropometry-tourdefrance.htm
 
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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #86 on: June 25, 2022, 09:06:16 pm »
But realistically, there are no pro BIG dudes.

Not among pro road cyclists, but there are some monsters out there among the pro track cyclists.

Fact.  check out the legs on that track cyclist in the toaster video.  Dude is a Beast!
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #88 on: June 26, 2022, 08:12:28 pm »
PV panels are cheap;

What's "cheap"? I look around and see they are about £1/W, which I wouldn't class as 'cheap', particularly why you need to add inverters and what not.
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #89 on: June 26, 2022, 08:21:27 pm »
PV panels are cheap;

What's "cheap"? I look around and see they are about £1/W, which I wouldn't class as 'cheap', particularly why you need to add inverters and what not.
New panels here in Lithuania are as low as 0.33€/W when on sale.
But most new panels are 0.45€/W.
Inverters and other stuff add up on top, of course.
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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #90 on: June 26, 2022, 10:30:53 pm »
Sounds like it might even be worth buying from there and paying import duty! If I could get that price here I'd seriously think about setting up a few panels (and arguing with the rest of the household where they can go).
 

Offline BrianHG

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #91 on: June 26, 2022, 11:44:48 pm »
A quality bike setup is more expensive than panels.  Do not expect scrounging together some random parts and a bike frame to last, be efficient enough & function when you really need it.

But, if you use your bike seriously for maintaining your health, IE create proper sound hardware, this may offset those $$$ concerns.
« Last Edit: June 27, 2022, 12:41:22 am by BrianHG »
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #92 on: June 27, 2022, 09:01:37 am »
PV panels are cheap;

What's "cheap"? I look around and see they are about £1/W, which I wouldn't class as 'cheap', particularly why you need to add inverters and what not.

Look at the context. In the context of "install 150Wp PV system", more panels are cheap, because installation costs, inverters etc. dominate the cost. There is also this difference that a too small of a PV system is still quite expensive and cannot run the fridge. A larger system is a lot cheaper per Watt, and will actually work, so inifinitely better than too small of a system.

Price of electricity is going sharply up, faster than PV system prices, so it's actually possible to make money on PV, now. So it's a really good idea to get a larger PV system in one go, instead of spending still relatively lot of money on a tiny system supposed to only run a fridge.

For example, I'm now selling to grid for around €0.20 on average, which is +300% increase in just a year or so. And the global energy crisis is real, it won't suddenly just go away.
« Last Edit: June 27, 2022, 09:03:22 am by Siwastaja »
 
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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #93 on: June 27, 2022, 09:13:24 am »
Quote
more panels are cheap, because installation costs, inverters etc. dominate the cost.

I'm going from the price of the panels. No inverters, fixings, labour, nothing. Just the panels.
 

Offline Cerebus

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #94 on: June 27, 2022, 12:23:12 pm »
A quality bike setup is more expensive than panels.  Do not expect scrounging together some random parts and a bike frame to last, be efficient enough & function when you really need it.

But, if you use your bike seriously for maintaining your health, IE create proper sound hardware, this may offset those $$$ concerns.

One of the most amazing things about bicycles in general, when compared to other machines, is how efficient they are. Even the rattiest old bike, as long as it has intact bearings, is over 90% efficient.

In any old cobbled together pedal powered generator the mechanical 'bike' component parts of it are probably going to be the least of your worries efficiency and reliability wise.
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Offline Siwastaja

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #95 on: June 27, 2022, 12:39:52 pm »
Quote
more panels are cheap, because installation costs, inverters etc. dominate the cost.

I'm going from the price of the panels. No inverters, fixings, labour, nothing. Just the panels.

Well... yeah. I think getting a 400W panel for 250EUR which is approximately the current situation, is a bargain. This 400W panel provides nearly 10MWh of "free" energy over its lifetime. The current value of this energy is very roughly around  2000EUR, but energy prices are only going to rise. And this is just considering the monetary value of energy for someone with reliable supply available. For those with unreliable or no grid... Having supply of electricity is definitely worth investing a few thousands. People use that kind of money shopping for throwaway clothes in a year, without blinking an eye!

And that's my point - if you need electric power, install enough PV to supply that. You will thank me later when you actually can keep the fridge running, and not only fridge but some lights, too, and also be able to post on EEVBlog forum, and even possibly use some modest amount of hot water which is hugely convenient. And having to start the gasoline genset much more rarely is definitely worth it. Of course for totally off-grid, it would be hard to completely avoid that.
« Last Edit: June 27, 2022, 01:11:21 pm by Siwastaja »
 
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Online tggzzz

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #96 on: August 26, 2022, 08:53:02 am »
Given the current energy supply problem in Europe, it is probable that there will be planned rolling electricity cuts this winter. I remember them back in "good old days" in the 70s, and India in the 90s.

This document, which is old but current, shows the effects of the cuts in the UK. I presume something similar would happen in other countries.
https://www.gov.uk/government/publications/electricity-supply-emergency-code

TL;DR: 19 levels from 0 (no cuts) to 18 (no power). Level 1 is a rotating 3 hour planned cut per day, level 17 is a rotating 3 hours of power per day. In between there planned 6 hour cuts and 9 hour cuts, progressively more of them as the level increases.

IMHO it is prudent in Europe (and that still includes the UK), to expect 3 hour cuts and think about 6 hour and 9 hour cuts.
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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #97 on: August 26, 2022, 08:57:37 am »
When considering powering freezers, the normal operating power and average power consumption are only part of the story.

Just as important is the current transient as the compressor start going.

I have seen transients of 5-10 times normal operating current for around 500ms. However, that measurement was on an old compressor (containing freon!) and I wouldn't want to presume new compressors have similar values. But I wouldn't preclude it either; research and measurement is required.
There are lies, damned lies, statistics - and ADC/DAC specs.
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Offline EEVblog

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #98 on: August 26, 2022, 11:17:49 am »
I plan on doing this soon. We have two fridge/freezers and a chest freezer.
EcoFlow are sending me a 3kWh portable battery which should have enough capacity to power them all.
I plan on having a manual mains timer that charges the pack durign the day from the solar (or whatever solar is available), and then power all the fridges and freezer and night. This would eliminate them from my household consumption, they'd be on entirely seperate systems.

I also plan on upgrading my Sunnyboy inverter to a hybrid inverter that has a backup mains output and that will do the same job. Can add battery storage to that to get emergency power to the fridges and other stuff if the power goes out. Could work with an in definite blackout.
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #99 on: August 26, 2022, 11:22:05 am »
Well... yeah. I think getting a 400W panel for 250EUR which is approximately the current situation, is a bargain. This 400W panel provides nearly 10MWh of "free" energy over its lifetime. The current value of this energy is very roughly around  2000EUR, but energy prices are only going to rise. And this is just considering the monetary value of energy for someone with reliable supply available. For those with unreliable or no grid... Having supply of electricity is definitely worth investing a few thousands. People use that kind of money shopping for throwaway clothes in a year, without blinking an eye!

Agreed, seems like a no-brainer.
Ecoflow also sent me two 400W portable fold out panels.

Quote
And that's my point - if you need electric power, install enough PV to supply that. You will thank me later when you actually can keep the fridge running, and not only fridge but some lights, too, and also be able to post on EEVBlog forum, and even possibly use some modest amount of hot water which is hugely convenient. And having to start the gasoline genset much more rarely is definitely worth it. Of course for totally off-grid, it would be hard to completely avoid that.

I thought about an entire house AC backaup battery system, but it's just not practical. It would have to huge and expensive, and requires extra cost in compliant installation etc.
So I thought a hybrid inverter with a smaller battery pack would do nicely for emergency power, as well as reducing by daily usage. The hybrid inverters have an emergency main output of a few kW that can power fridges and essential gear if needed.


 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #100 on: August 26, 2022, 01:59:06 pm »
Given the current energy supply problem in Europe, it is probable that there will be planned rolling electricity cuts this winter. I remember them back in "good old days" in the 70s, and India in the 90s.

This document, which is old but current, shows the effects of the cuts in the UK. I presume something similar would happen in other countries.
https://www.gov.uk/government/publications/electricity-supply-emergency-code

TL;DR: 19 levels from 0 (no cuts) to 18 (no power). Level 1 is a rotating 3 hour planned cut per day, level 17 is a rotating 3 hours of power per day. In between there planned 6 hour cuts and 9 hour cuts, progressively more of them as the level increases.

IMHO it is prudent in Europe (and that still includes the UK), to expect 3 hour cuts and think about 6 hour and 9 hour cuts.
I would like to see a program where people can elect to get paid to be first to be disconnected.
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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #101 on: August 26, 2022, 02:08:04 pm »
Given the current energy supply problem in Europe, it is probable that there will be planned rolling electricity cuts this winter. I remember them back in "good old days" in the 70s, and India in the 90s.

This document, which is old but current, shows the effects of the cuts in the UK. I presume something similar would happen in other countries.
https://www.gov.uk/government/publications/electricity-supply-emergency-code

TL;DR: 19 levels from 0 (no cuts) to 18 (no power). Level 1 is a rotating 3 hour planned cut per day, level 17 is a rotating 3 hours of power per day. In between there planned 6 hour cuts and 9 hour cuts, progressively more of them as the level increases.

IMHO it is prudent in Europe (and that still includes the UK), to expect 3 hour cuts and think about 6 hour and 9 hour cuts.
I would like to see a program where people can elect to get paid to be first to be disconnected.

Commercially that has existed for a long time; they got a cheaper tariff.

There used to be a cheap "overnight tariff" complete with separate meter for hones that were prepared to use electricity to heat a pile of bricks in their room.

It is already being suggested that people with smart meters will paid (whatever that might mean) if they don't use large loads in peak hours.
There are lies, damned lies, statistics - and ADC/DAC specs.
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Online themadhippy

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #102 on: August 26, 2022, 02:55:19 pm »
Quote
There used to be a cheap "overnight tariff" complete with separate meter for hones that were prepared to use electricity to heat a pile of bricks in their room.
Economy 7  is still here,a saving  for those of us who are nocturnal and have it configured so the cheap rate applies to the whole house,not just the pile of bricks
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #103 on: August 26, 2022, 07:33:19 pm »
So uh, it's fun, but also concerning, that threads like this one are starting to pop up... We were like poking fun at all those survivalist lunatics, and now we're slowly but surely becoming part of the movement. ::)
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #104 on: August 26, 2022, 11:28:52 pm »
I would like to see a program where people can elect to get paid to be first to be disconnected.
As mentioned above this is already common/routine for large consumers, they lock in a lower supply rate in return for allowing the grid operators/regulator to enact demand management. Sometimes with explicit compensation during the downtimes, sometimes without and amortising that over a cheaper default rate. But, when the events are actually imminent/occurring those people getting the benefit of cheaper rates for this supposed stability/supply benefit to others....
https://www.2gb.com/breaking-matt-kean-tells-sydney-to-reduce-energy-usage-between-5-30pm-and-8pm-tonight/
The politicians/operators ask everyone else to kerb their usage, so industry isn't disrupted! We have the same issue with water, massive restrictions on domestic use while cotton farmers take their "entitlements" despite the poor overall economic return.

Demand management to households is experimental/trial stage:
https://www.energymining.sa.gov.au/industry/modern-energy/solar-batteries-and-smarter-homes/south-australian-demand-management-trials-program
https://www.evoenergy.com.au/emerging-technology/demand-management
But most of the models are "aggregation" where an intermediate operator hides the complexities from the customer (and takes the profits along with the government grants).

Consumers in Australia aren't individually exposed to wholesale pricing fluctuations, so have almost no incentive to reduce peak/constrained use as the marginal cost its averaged across every consumers bill. Rather than being paid to be disconnected, charging a spot rate of $XXX.XX per kWh would make people think twice about the importance of their energy use just as petrol prices fluctuate. The challenge is how to communicate this to consumers in a "fair" way, day ahead? hourly? Consumers railed against time of use tariffs because they were priced with no actual incentive to shift power use unless you had some enormous load like an EV or a pool heater.

Once the monetary incentive is there, then products will appear to address the savings. Hot water storage (and for the UK hot bricks for heating) was common when the overnight off peak tariff made it economic, the exact same technology can be flipped to hot water storage during the day when solar production drives the price down, but there is some unknown/weird blockage in the economic system that continues to not expose that to the consumer.
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #105 on: August 27, 2022, 12:59:07 am »
It is already being suggested that people with smart meters will paid (whatever that might mean) if they don't use large loads in peak hours.
That's what Ohmconnect does.
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Offline Alti

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #106 on: August 27, 2022, 11:34:19 pm »
but there is some unknown/weird blockage in the economic system that continues to not expose that to the consumer.
That would have required quite a different metering system. Metering is managed by distribution companies and these companies have monopoly over certain territory. They won't earn less or more, rates of monopolists are always dictated by local authorities. From a monopolist's point of view there is no initiative in increasing sales volume and lowering unit price. Economy 101.
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #107 on: August 28, 2022, 01:03:13 am »
but there is some unknown/weird blockage in the economic system that continues to not expose that to the consumer.
That would have required quite a different metering system. Metering is managed by distribution companies and these companies have monopoly over certain territory. They won't earn less or more, rates of monopolists are always dictated by local authorities. From a monopolist's point of view there is no initiative in increasing sales volume and lowering unit price. Economy 101.
It could well be the distribution company preventing this, but metering is not the limitation here in Melbourne/Victoria where every residential customer was required to install (at their expense!) a smart meter.
https://www.energy.vic.gov.au/electricity/smart-meters
Promises of future benefits:
https://www.victorianenergysaver.vic.gov.au/get-help-with-your-bills/smart-meters-and-how-they-work
"Flexible pricing" "Smart appliances" still coming soon, 10 years after the metering and billing system was already in place
 

Offline Alti

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #108 on: August 28, 2022, 08:53:52 am »
but metering is not the limitation here in Melbourne/Victoria where every residential customer was required to install (..) a smart meter.
I meant that if you want flexible electricity pricing, it has to be beneficial for a distribution company (which governs metering) and not that you need to upgrade a power meter and you are done.

A monopolistic market does not act according to free market rules. To get their revenues, they do not have to introduce risky changes, take initiatives or satisfy demand and supply. It is enough they justify the necessary increase in distribution costs and expenses,
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unusual conditions are affecting Australia’s east-coast energy market
or
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Smart meters are now in place in all Victorian homes, providing benefits that were not available with the accumulation meters.
and they are happy, they get their funds, even if those meters are just an expensive paperweight.
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #109 on: August 28, 2022, 09:13:35 am »
A monopolistic market does not act according to free market rules. To get their revenues, they do not have to introduce risky changes, take initiatives or satisfy demand and supply. It is enough they justify the necessary increase in distribution costs and expenses, ... and they are happy, they get their funds, even if those meters are just an expensive paperweight.

Be careful about introducing naive market, economic and political concepts - both in real life and on this forum.

The UK introduced market competition in the form that consumers could buy their gas and electricity from many different companies. The companies, of course, competed on price, and consumers frequently swapped the company supplying their energy.

This year many of those companies have entered bankruptcy, because they could no longer supply the energy at the price in the contract with the consumer.

In order to avoid riots, the government arranged for other companies to "take over" the consumers from the failed companies, including the credit balances that consumers had with the failed companies, even though those balances has already been spent. The consequence is that every consumer of electricty is now forced to pay a much higher price; the daily "standing charge" has risen from, IIRC ~5p/day to ~30p/day. There are much higher per-kWh charges are on top of that, of course.

Hence your contention about monopolies vs free markets is very naive.
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Offline Someone

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #110 on: August 28, 2022, 11:03:39 am »
but metering is not the limitation here in Melbourne/Victoria where every residential customer was required to install (..) a smart meter.
I meant that if you want flexible electricity pricing, it has to be beneficial for a distribution company (which governs metering) and not that you need to upgrade a power meter and you are done.

A monopolistic market does not act according to free market rules. To get their revenues, they do not have to introduce risky changes, take initiatives or satisfy demand and supply. It is enough they justify the necessary increase in distribution costs and expenses
To be accurate, the Australian market has distribution, generation, retail, all separated. So the distribution company has very little say in the per unit price of energy or how the tariffs are structured/timed (but majority say in the connection cost).

As with the UK mentioned above, the competitive retail companies are falling over on their own as they sold power without the futures to lock in the price. Prices went up more than anyone was expecting and now the small retailers are both losing money and running out of liquidity (going bankrupt).
 

Offline Alti

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #111 on: August 28, 2022, 11:27:50 am »
The UK introduced market competition in the form that consumers could buy their gas and electricity from many different companies.(..)Hence your contention about monopolies vs free markets is very naive.
The UK introduced market competition between consumers and producers. This has nothing to do with distributors. Distributors are monopolists over their territory.

I meant that if you want flexible electricity pricing, it has to be beneficial for a distribution company (which governs metering)(..)

I think that the misunderstanding here comes from beliefs the energy distribution, with power grid limitations, its maintenance, upgrades (and metering system) is controlled by producers and consumers according to the rules of free market.
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #112 on: August 28, 2022, 10:44:59 pm »
The UK introduced market competition in the form that consumers could buy their gas and electricity from many different companies.(..)Hence your contention about monopolies vs free markets is very naive.
The UK introduced market competition between consumers and producers. This has nothing to do with distributors. Distributors are monopolists over their territory.

How could that be otherwise?

Or are you proposing duplicating transmission infrastructure?
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Offline SiliconWizard

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #113 on: August 29, 2022, 12:03:48 am »
Indeed. Many large-scale infrastructures are monopolistic by nature. That can't be otherwise. And that is exactly where the free competition fantasy for those markets begins. It's the same shit everywhere in the EU since competition was forced upon EU members for absolutely EVERYTHING, even markets for which it didn't make much sense at all, and the nonsense is exacerbated in Europe for the simple reason that european countries are small (compared to the USA at least, for instance) and thus can't individually handle infrastructures of different parts of the country. Just not possible.

What this brought was a bunch of energy providers that just jumped on the bandwagon to get their share, and with very little to zero added value, since what they are doing is just resell energy that they are buying from "monopoles" anyway. Very efficient. So to make a difference, they just cut their operating costs as much as possible and even so, that often ends up not being viable long term so a number, if not most of them, are bound to go bankrupt. That's just a completely fucked-up and artifiial economic system that defies common sense.

So anyway, true competition can make things more resilient, but this artifical form of competition is never going to. There's still a "single point of failure", and since the handling of energy matters is fully in the hands of politics/states, it's never going to follow rules of a free market either.
« Last Edit: August 29, 2022, 12:13:28 am by SiliconWizard »
 

Offline james_s

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #114 on: August 30, 2022, 12:51:00 am »
Normally I would say that competition is always a good thing, but for something like electricity which is delivered on a national grid it has never made any sense to me and I'm glad I don't have to fuss around with choosing an electricity supplier. It all comes from the same generating plants and is distributed over the same infrastructure so what is one choosing? A billing service?
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #115 on: August 30, 2022, 01:40:19 am »
It all comes from the same generating plants and is distributed over the same infrastructure so what is one choosing? A billing service?
The theory being that smaller retail margins and "novel" tariffs would not exist if there was a monopoly retailer...
Reality is that the profit has shifted to the active market (speculation and financial instrument liquidity in generation) and the public are no better or worse off. Where before a massive vertical conglomerate (government owned or not) would be taken to task if they raised prices while making record profits, now its spread across a complex series of opaque transactions/companies and the general public cant see who to blame.

It's not coming from the same generating plants, as there are many "players" at that end who are enjoying the wholesale market they can manipulate with synthetic shortages, removing the cheapest energy sources increases their profits.
 

Offline ryan_zheng

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #116 on: August 30, 2022, 02:32:14 am »
I would say a generator with a large AC portable power station would be best for this. Or use generator and dedicated battery and inverter. In this setup you hook the fridge and other low wattage appliances that require continuous power to the battery power station, other large loads to the generator, and connect the charging input of the power station to the generator as well. This way you only fire up the generator when using very large loads or when noise is not a concern. Fridges can be easily powered by the battery whenever generator is out.

Also I'm surprised nobody has mentioned propane fridge(fuel gas refrigerator). These are propane powered and are mainly for RV use but many also accept mains power or 12~24V DC power. These use absorption refrigeration and use heat as energy source so both a propane flame or a electric heater can power these. If you don't have a lot of other appliances to justify a generator you can use on of these. Use electric when there is power, and switch to propane when power is out.

EDIT: sorry for my blindness and stupidity. It was mentioned, twice, on the 1st page
« Last Edit: August 30, 2022, 05:42:40 am by ryan_zheng »
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #117 on: August 30, 2022, 02:47:04 am »
I would say a generator with a large AC portable power station would be best for this. Or use generator and dedicated battery and inverter. In this setup you hook the fridge and other low wattage appliances that require continuous power to the battery power station, other large loads to the generator, and connect the charging input of the power station to the generator as well. This way you only fire up the generator when using very large loads or when noise is not a concern. Fridges can be easily powered by the battery whenever generator is out.
Delta recently came out with a portable battery system with matching automatic start generator. But if the generator is going to be infrequently used which is the case in most areas, it would make more sense to have a car double as the generator.
Quote
Also I'm surprised nobody has mentioned propane fridge(fuel gas refrigerator). These are propane powered and are mainly for RV use but many also accept mains power or 12~24V DC power. These use absorption refrigeration and use heat as energy source so both a propane flame or a electric heater can power these. If you don't have a lot of other appliances to justify a generator you can use on of these. Use electric when there is power, and switch to propane when power is out.
The efficiency is pretty poor, a regular refrigerator running from a generator would get similar or better efficiency.
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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #118 on: August 30, 2022, 05:11:35 am »
Quote
The efficiency is pretty poor, a regular refrigerator running from a generator would get similar or better efficiency.
Indeed, but if the OP doesn't need anything else to be powered electrically apart from the fridge, a propane fridge may be suitable. So that they will not need any backup electrical power source, and a gallon of propane would last a really long time powering that fridge.

In the case someone already have gas lantern, gas cooktop/oven and gas water heater with battery ignitor, a propane fridge would really make sense here.
 

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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #119 on: August 30, 2022, 05:30:10 am »
Also I'm surprised nobody has mentioned propane fridge(fuel gas refrigerator).
Twice on page 1, it got there really quickly!
anyone with any sense would be getting a gas powered fridge for that, as already hinted at:
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Re: A possible way to keep your fridge cold in long term blackouts.
« Reply #120 on: August 30, 2022, 05:41:48 am »
Quote
Twice on page 1, it got there really quickly!

I must have been blind. Went through it again, guess the word "gas" wasn't as obvious as "propane" and also I failed to recognize that brand and model name.
 


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