The refrigerator consumes about 8% of a home's electricity. It's is far and away the single most energy-intensive appliance. But it serves an important purpose. It keeps our beer cold. Also, it keeps our food cold. There are a half-dozen ways of greening up your fridge: Keeping it full, covering the food, cleaning the compressor coils, etc.
A book called the Carbon-Free Home suggests a novel way of dealing with the fridge's energy consumption. The book's authors explain that we can carpet our fridge.