I have always wondered about this one... Refrigerators are one of the top energy consumers in homes. In Northern climates, the outside temperature is colder than indoor temperature at least 6 months of the year.
Why aren't they designed with "heat" exchangers to benefit from cool if not frigid external air?
Even in warm climates (or summers) why isn't the same principle used to vent the warm air from the compressor & coils outside rather than loading the AC?
Presumably this could all be done by putting the evaporator coils outside which would in turn decrease (or eliminate if cold enough) the draw on the compressor during winter months.
Of course, installation might be a little more expensive, but with all the focus on green-this and green-that why isn't this being done?