I have heard that it is better to leave your fridge open while, say, pouring a glass of juice or some other short task, rather than opening it, getting out the juice, closing it, pouring the juice, and then opening it back again to put the juice away. The reason I was told was that the suction created by opening the door pulls more cold air out than would flow out if it just sat open.
It makes sense, but then… air moves around pretty easily and it seems like it wouldn’t take being open very long at all before you would have lost that much air and more.
So which is more efficient? (I have also heard that storing your empty tupperware, sealed, in the fridge saves energy, because it traps the cold air in…