enough babble. i bet somebody’s confused. in any sense, i put my computer on to download non-stop over the course of winter to function normally while heating my house to a nice comfy temperature without ever feeling guilty about being green. On that note, people ACTUALLY using heaters are the ones contributing to this greenhouse problem we’re facing.

You said “Not so! Oh wise one. You are paying to heat the inside as heat seeps in and then paying to cool it down again.”

It is so. This is the law of conservation of energy. It’s basic highschool physics and I am frankly surprised at the number of people who are disputing it. ALL the electricity you put into a fridge is effectively released as heat into your home. The fact you are pumping heat around at the same time is completely irrelevant. The net result MUST be heat generation equivalent to the electrical consumption. If your fridge draws 100W of electrical power on average, then on average it outputs 100W of heat. Where do you suppose the energy goes otherwise? As far as your house is concerned, a fridge (or any electrical appliance) is just an electric heater. If you heat your home with electricity, it makes little difference to your cost whether you do it with heat from a refrigerator, light bulbs, toaster, or any other electrical appliance.

Not so! Oh wise one. You are paying to heat the inside as heat seeps in and then paying to cool it down again.

The lower maximum of -18C is probably safety factor to some extent–neither thermostats nor thermometers are noted for their accuracy–thermometers which are readable to .1 degree often have an uncertainty of up to 1 degree. And the actual reading may be far from that–take a look at all of th thermometers at a store display and you’ll see how inaccurate they are…lab thermometers are often only good to +-.5 to 1 degree.

Bacteria are not the only reason to refrigerate!

Food loses quality for chemical and physical reasons too.

For example, ice cream needs to be kept below -20F (-29C) if it is to retain it’s polycrystalline structure (which affects mouth feel.) The colder you keep things the slower any chemical reactions will happen, and they can alter the flavor or nutrient values.

Better insulation combined with a chest style opening (which can be obtained by converting a chest freezer to a refrigerator–which may be as easy as adjusting the thermostat.)

Even a relatively inefficient chest freezer will run much more efficiently as a refrigerator than the best cabinet door refrigerators.

Best for all purposes are the under cabinet drawer units, which combine the convenience of the front opening with the efficiency of the chest.

But drawer units are rare and expensive. Cheap chest freezers abound. If you can afford the space, a larger chest refrigerator can be adapted to have things like pressure strut lifts to lift the top foods above the edge of the chest to work on the bottom foods. If you can find a cheap used unit, you can play with such things until you decide what you like best–you could even modify a chest to have drawers, though it would take some fair handyman skills to do, it’s not really complex,but like most things, it will take some time.

Thermostats often have two adjustments, one is the knob you can see, the other is a screw which adjusts the contact spacing.

When working with a conversion, find out what the highest temperature the freezer will hold at–if it 34F or above, you really shouldn’t need to change anything. Just measure the temperature at the bottom to see the difference–you should be able to store warmer holding freezer items in the bottom of the chest.

Ideally you have multiple compartments and use small fans to move cooler air in as needed–allowing individual temperature chambers. These thermostats are much cheaper because the load for a fan is quite low compared with a compressor.

If you heat with something other than electricity, the comparison is not as simple. In the example I gave in an earlier comment, I showed that for heating with a 90% efficient natural gas furnace and assuming prices similar to where I live, the freezer would need to see a 79% reduction in electrical consumption for outside operation to cost less than inside operation. I said above that this kind of reduction is unlikely, but it is possible depending where you live. Assuming your freezer thermostat is set for -20C and assuming energy consumption roughly linear with temperature difference between inside and outside the freezer, you could see a 79% reduction in energy consumption if the average outside temperature during your heating season is below -12C. Where I live, the average outside temperature during my heating season is closer to 0C so I’d be better off keeping my deep freeze inside, even if I heated with natural gas.

In so much as a thermometer sees the average temperature inside a fridge, so does your food. Most food has a much greater thermal mass than a thermometer, so the temperature of the food will fluctuate even less than that of the thermometer. Air temperature in the fridge will fluctuate most (it must, or the thermostat would not trigger the compressor to turn on and off) but the temperature of the food stays relatively constant (the same as the temperature indicated by the thermometer). Foods of low thermal mass (loosely packed, leafy plants for example) will experience the greatest temperature fluctuation.

An empty fridge should not take half a day to cool down warm air that is allowed to enter it. The specific heat capacity of air is 1297 J/(m^3 degC). A large fridge might contain 1 m^3 of air. Assume the entire volume of air is replaced with room air at 22C and the air must be cooled by 20 degrees to 2C. The amount of energy to be removed is therefore 1297*20 J (Joules). A Watt is a J/s (Joule per second). Assume the fridge consumes 100W and has a COP (coefficient of performance) of 1 (very conservative). Therefore 100 J are removed each second and it will only take a little over 4 minutes to cool down the warm air. It is a different story if the entire fridge starts at room temperature. Then parts of the fridge must be cooled down in addition to the air so it will take more time, but probably still much less than half a day.

Where I live gas costs about $0.05/kWh and electricity costs about $0.07/kWh. Assume a gas heating efficiency of 90% (optimistic since most furnaces are less than 90% efficient). Suppose you have a freezer that consumes 100W if located inside during the heating season. Moving it outside will therefore cost you 100/0.9 = 111W of additional natural gas consumption. Given the relative cost of gas vs electricity, you would need to save at least 79W of electricity to make it worthwhile. So unless moving the freezer outside reduces its electrical consumption to 21W or less (a 79% reduction), you are better off keeping the freezer inside. I think that kind of reduction is very unlikely.

To conclude, generally speaking, no matter what method you use to heat your home, you are likely to save money by having your freezer (or any other electrical appliances) operate inside your home rather than outside during your heating season. However, the reverse is true during the cooling season if you use air conditioning.

The actual temperature-figures you have mentioned would certainly help me in setting the fridge to a more practical level, and significantly reduce consumption.

Regards,

Anand

Also, the deep freeze located in the garage will consume less energy during the heating season. If you’re making the argument to save money, it makes more sense to consume less electricity by leaving it in the garage and use a little more natural gas to heat your home.

A great book that you may find helpful is Carbonbusting for fun and profit, written by a local (to me) Edmontonian. I hope this is useful information to you.

Cheers,

Jason