Refrigerators take up sinful amounts of space. Worse, they suck more energy than any other household appliance (unless you’ve got a pool or a spa). French industrial designer Nicolas Hubert has an idea that gets at both problems in one clever — if flawed — move: Hang the fridge outdoors.

The conceptual External Refrigerator clamps onto your building’s facade outside a window and chills food naturally in cold weather and at night. When it’s sunny, solar panels power the appliance’s cooling mechanism. The whole thing could probably slash your fridge’s carbon footprint to zero, depending on where you live. And, of course, it frees up space at home for other stuff (a spa, for instance). Here’s a quick vid on how it works:

Sounds great, right? The devil, though, is in the details. To get at your food, you’ve gotta throw open the window, then slide out a panel of shelves. So now, making a sandwich involves an extra step — a trifling matter for the most part, unless, of course, you’re in Minsk in the dead of winter, when even cracking your window is an invitation to frostbite.

Plus, a facade attachment just won’t work for a lot of households. Think if the window in your apartment is in the bathroom. Do you really want to put a refrigerator there? Or if you live in a building with no operable windows at all. Or if you live on the 30th floor of a Manhattan high rise, and whoops there goes the chardonnay bottle, nose-diving, missile-like, to some pedestrian’s grave misfortune.