How long does a freezer stay frozen when the power goes out? • Hacker News Board

Re: How long does a freezer stay frozen when the power goes out?

#341

Post by supernova87a » Mon, Aug 10, 2020, 5:24 PM UTC

pedrocr wrote: post #301

pfdietz wrote: post #239

Earlier quoted context omitted.

An inverter that runs off the 12V battery in your car is very cheap. Get one, and an extension cord, and you have an emergency power source to cool down your freezer every few days.

That's one thing that's annoying in the current crop of EVs. Almost none of them support drawing power from the cars even though they have those huge batteries just standing there. I understand not wanting to add the cost of the inverter to every car but it seems it should be relatively straightforward to support external inverters that plug into the DC part of the CCS connector.

I think it's because the car companies don't want people meddling, draining their car batteries with poor power management and degrading the lifetime, and then coming to them and asking them to repair the damage.

Re: How long does a freezer stay frozen when the power goes out?

#342

Post by dr_zoidberg » Mon, Aug 10, 2020, 5:33 PM UTC

woobar wrote: post #340

wtvanhest wrote: post #326

Earlier quoted context omitted.

There is a good trick to use if you leave on vacation (or for monitoring breast milk for those new parents). You can freeze a cup of water, and throw a coin on top. If your freezer melts at any point, the coin will be at the bottom, not the top of the water glass when it refreezes.

Ice floats. Even if the most of the ice in the cup has melted, but there was a little bit of it left, the coin will stay on top. From my personal experience: while we were away on vacation, there was a power outrage for 24_ hours. Coin was on top, but all ice cream and frozen packaged food was ruined. Not sure about big chunks of beef.

A similar tip is to leave an ice cube of of a tray, or in a bag. If the cube is out of shape when you return, it thawed.

Re: How long does a freezer stay frozen when the power goes out?

#343

Post by woobar » Mon, Aug 10, 2020, 5:38 PM UTC

syshum wrote: post #255

todd8 wrote: post #182

A simple way to detect power failure induced thawing in a freezer is to store a paper cup about half full of frozen water in the freezer. By keeping a coin on top of the ice it’s easy to see with a quick glance if the temperature has risen for an extended period of time (possibly due to a temporary power failure or the door not being fully closed).

It is possible for the Ice to partially melt and the coin to not sink, the ice would need to COMPLETELY melt before this test would work, given the nature of ice it is possible for food to raise to an unsafe temperature while the ice is still melting This "trick" should not be used in place of proper temperature monitoring

You are correct. I've shared my personal experience above[1]. Coin will stay on top of the floating piece of ice even if 90% of water has melted.

[1]https://news.ycombinator.com/item?id=24111666

Re: How long does a freezer stay frozen when the power goes out?

#344

Post by tonyarkles » Mon, Aug 10, 2020, 5:44 PM UTC

dctoedt wrote: post #323

tonyarkles wrote: post #266

Earlier quoted context omitted.

I’m laughing a bit thinking of the absurdity going on in my brain. While reading the parent comment there were two parallel streams going on in my brain: “That is so awesome that the community rallied together like that” “What the duck are they doing having a large gathering in their yard?! Surely they could have figured out a safer way to do that! If someone got COVID during a hurricane with no power that could be r…

GP commenter here — I assume you re-read my comment and realized that this was in September 2008 .... :-)

Hahahaha yes. That's when I realized that it was totally reasonable and that my brain's mental model of the world has been thoroughly rewired...

Re: How long does a freezer stay frozen when the power goes out?

#345

Post by woobar » Mon, Aug 10, 2020, 5:49 PM UTC

enaaem wrote: post #199

morninglight wrote: post #64

The location of the freezer or refrigerator is critical. If you live in a house that has a typical unfinished basement, don't overlook the advantage it offers. With one simple change, you can noticeably lower your electric bill, reduce your carbon footprint, gain extra kitchen space and improve your health. Just move your refrigerator to the basement. Since the basement is normally cooler than the upstairs, the refri…

Also, get a chest freezer. They are much more efficient. Every time you open a standing freezer, the cold air "false out", since cold air is more dense than warm air. The chest freezer on the other hand will hold the cold air in place.

They are more efficient in keeping the food frozen. But they are less efficient in getting the food out of it. This is how you find 5 year old products at in the bottom of the freezer when you finally clean it up.

Re: How long does a freezer stay frozen when the power goes out?

#346

Post by mariuolo » Mon, Aug 10, 2020, 6:04 PM UTC

an-allen wrote: post #154

Hi. Actualexperience here... it depends on the ambient temperature and how much stuff is in said freezer. So heres a data point: Freezer: normal upper level refrigerator freezer chock full of frozen fish caught on holiday in Alaska. Place, Time: Houston, TX, Late Summer, Hurricane Igor just hit and knocked our power out for 14 days. Findings: We kept the freezer shut and at about 4-5 days the fish was noticeably thaw…

> At day 8 or so it had completely defrosted.

It's unclear why you didn't throw it away at this point.

Was it an experiment?

Re: How long does a freezer stay frozen when the power goes out?

#347

Post by 8note » Mon, Aug 10, 2020, 6:07 PM UTC

It would be nice to see the rest of the thermal analysis, and see if it matches the provided specs

Re: How long does a freezer stay frozen when the power goes out?

#348

Post by Xylakant » Mon, Aug 10, 2020, 6:23 PM UTC

jayrot wrote: post #330

ghaff wrote: post #293

Earlier quoted context omitted.

I had never thought about this but you're right. Big frozen water/soda bottles of ice still increase the overall thermal mass and will almost certainly slow full thawing. Otherwise, ice blocks in a cooler wouldn't work. But you're really better off adding salt to those bottles so they absorb energy when melting below the freezing point of pure water (and frozen food).

While that's true, since the current topic of this conversation is about emergency preparedness, I think having potable water (in ice form) would be much preferable to salted water.

It’s substantially more efficient to store a pack of bottled water or two on top of your fridge - and keep your food at the same time. Water keeps well even if not frozen.

If you want to keep tap water, you can buy silver ion additives at any camping/outdoor store. If you’re really planning for preparedness, buy a ceramic water micro filter and additives. That can make nearly all water usable.

Re: How long does a freezer stay frozen when the power goes out?

#349

Post by copperx » Mon, Aug 10, 2020, 6:25 PM UTC

jaypeg25 wrote: post #292

papito wrote: post #253

Earlier quoted context omitted.

Ice cubes always taste funny if used without good ice forms, absorbing the fridge odors. Use the ones with silicone cover. Not a hint of the freezer in the made ice.

I got these mostly because space is a luxury in our freezer (very tiny) and wanted to vertically stack them. I love them. It's such a weird thing to throw praise on, but I've literally told friends to get the silicon cover ice trays and never look back.

The cover is silicon, but the tray is regular plastic?

Re: How long does a freezer stay frozen when the power goes out?

#350

Post by sizzle » Mon, Aug 10, 2020, 6:40 PM UTC

csours wrote: post #285

an-allen wrote: post #154

Hi. Actualexperience here... it depends on the ambient temperature and how much stuff is in said freezer. So heres a data point: Freezer: normal upper level refrigerator freezer chock full of frozen fish caught on holiday in Alaska. Place, Time: Houston, TX, Late Summer, Hurricane Igor just hit and knocked our power out for 14 days. Findings: We kept the freezer shut and at about 4-5 days the fish was noticeably thaw…

PSA: I've worked disaster relief/reconstruction in Houston, New Orleans, and a few other places. If you come across a fridge with the doors taped shut DO NOT OPEN IT. If you come home after power was lost for more than a day or so, TAPE THE DOORS OF YOUR FRIDGE SHUT AND DO NOT OPEN IT. It's not worth it. You will never make the fridge use-able again. If you have to leave ahead of a disaster, consider emptying your fr…

If you refreeze rotten food, doesn't that reduce the smell released, like less odor is wafting around in the air from frozen meat than warmed up meat?

Like we are able to find preserved remains in ice of people who perished in these harsh climates, as opposed to a warmer climate where all the tissue would be putrid immediately.