General Question

LostInParadise's avatar

Would it be more efficient in winter to have refrigerators and freezers be able to draw air from the outside?

Asked by LostInParadise (17718 points ) February 10th, 2013

This seems like such an obvious question that there must be some reason why it is not done. It seems like such a waste to have cooling units compete against the indoor heating system, when they could just suck in air from outside. Some people keep freezers in their garages. I would think that such units draw very little power in winter.

Observing members: 0 Composing members: 0

13 Answers

CWOTUS's avatar

Food in my outside refrigerator freezes in the winter. It’s not such a great idea.

As far as cooling, it’s cold as hell, though.

woodcutter's avatar

A freezer is a self contained machine so it won’t matter what the temp of the outside air is. It’s an insulated box. If you live in a climate that will stay below freezing temperature all the time then you could keep the contents in some kind of box that uses no power. If one was ingenious type they might use a freezer with the back removed sitting in a hole in an outside wall but then they would need to do something different when the weather warmed.

For items needing refrigeration only then the outside air would be too cold.

LuckyGuy's avatar

Yes it would save money IF you lived in the right climate, had the right kind of air controls, and used it properly.

I live in a cool/cold climate. Where I live, any food stored in a refrigerator outside would freeze. That might be ok for some things but not for others.
I do not have air conditioning and need some heat in my house for 10 months out of the year. The energy used to run my refrigerator is a direct replacement for the heat my furnace would need to put out. Every kWhr of energy used to run the refrigerator puts heat into my kitchen and heats my house. It displaces an equivalent amount of oil that would be consumed by my furnace.

If you live in a warm or hot climate it might make sense to reject the heat to the outdoors but would you be willing to make another opening in the wall of your house to save a few dollars?

XOIIO's avatar

It would need some sort of regulation, an insulated valve that could open/close and a fan that would draw the air in but only at a certain temperrature, because it would need to be just right. Here in canada (saskatchewan) it easily gets down to -30 and that would ruin food.

LostInParadise's avatar

@LuckyGuy , I forgot about the heat produced by refrigerators. That does help with the overall energy in winter, and in summer the air conditioning in the house lowers the amount that the refrigerator has to work.

@XOIIO, The mechanism would have to be as you described. With proper insulation, it would only be necessary to bring in a very tiny amount of that -30 degree air to achieve the right temperature.

LostInParadise's avatar

Thinking about this some more, depending on the location of the refrigerator, the biggest problem with the idea would be that any cold air that escaped into the house might cause the heating system to work harder than the savings on the work that the refrigerator does.

mattbrowne's avatar

Of course it can be done in any climate whether the outside temperatures are (partially) colder than the inside temperatures. The best approach is leaving the fridge in the kitchen near an exterior wall connected by smartly insulated exchange pipes with small fans and a sophisticated system to control air flow. As long as electricity is so cheap and destroying our atmosphere remains free of charge such installations can’t compete with the existing ones.

LuckyGuy's avatar

Just to put some numbers on it. According to the Consumer Energy Commission the average refrigerator uses 680 kWhr of electricity in year. At 12 cents per kWhr that is $81 per year.
I used a Kill-o-Watt meter to measure my own refrigerator, a relatively new, large GE (without ice maker) and got 470 kWhr /year or $56.40. I need heat for 10 months of the year and do not have air conditioning the refrigerator is basically free for those months since it replaces the heat my normal heating system would need to produce.
Let’s address the other 2 months of the year when it costs me something. That is a total of $9.40 in a year. Even if I managed to do something miraculous so it cost nothing, the time and effort would not be worth the trouble for $9.

Take the other extreme, where you live in a hot climate with A/C needed all the time and electricity costs $0.25 per kWhr. (Maybe @mattbrowne can say how much he pays.) My same refrigerator would cost you 470 kWhr to run the refrigerator + (est.) 1.5×470 kWhr in air conditioning costs to get rid of the heat. 1175 kWhr x 0.25 = $294 per year. Now you have a reason to do something. Maybe.
If you vent all the refrigerator heat out of the house you will save on the a/c cost but you will be drawing in outside air that is presumably hot causing your a/c unit to work harder.

The best energy saving technique you can do is buy a refrigerator that is sized so you keep it full most of the time. Keep water bottles in it if you have the empty space. They will be handy in an emergency and will keep the food cold longer if you lose power.

mattbrowne's avatar

One kWh in Germany costs about 25 euro cents. A transition to pipe-equipped fridges would take decades and makes most sense when erecting new buildings. The benefit would certainly be smaller compared to investing the same amount of money into insulation of walls and windows against heat and cold. Good windows are the “big rocks”. The Fluther question was “would it be more efficient” and the answer is yes. But for the transition into a green infrastructure we should invest first in areas we get the most quick return and that’s insulation of buildings. Smart fridges might become a widespread reality in 2050 or later.

LuckyGuy's avatar

@mattbrowne Thanks for getting back to us here. So at today’s exchange rate, you pay $0.33 per kWhr. Almost 3x the price we pay. That is why you are willing to spend more money on efficient appliances. The higher initial cost is offset by the lower operating expense.

mattbrowne's avatar

Do you know this approach?

http://en.wikipedia.org/wiki/European_Union_energy_label

It makes people feel good paying a bit more and be the proud owner of a A+++ fridge, washing machine, tv set.

If the US doesn’t catch up this will eventually costs millions of American jobs. European companies have more incentives to innovate and come up with more and more efficient products.

LuckyGuy's avatar

We have a labeling system but it is not as colorful and detailed. It tells the annual consumption and estimated cost. Sadly most people figure it is so cheap why worry? “Why should I pay $400 more for an appliance if it will only save me $15 per year? Let’s go buy the bigger one.”
This is short sighted thinking but very real.
Most Americans will buy the least expensive option even if it costs the jobs of their neighbors. I offer WalMart as proof.

mattbrowne's avatar

Isn’t the FairTrade idea catching on?

Answer this question

Login

or

Join

to answer.

This question is in the General Section. Responses must be helpful and on-topic.

Your answer will be saved while you login or join.

Have a question? Ask Fluther!

What do you know more about?
or
Knowledge Networking @ Fluther