Tame the room's biggest energy hog: the refrigerator. First, make sure the temperature isn't too low. The fridge should be at 37 degrees, the freezer at 3 degrees. Then do a little fridge feng shui: Don't stuff it, but make sure it's adequately stocked so it doesn't have to work hard to cool empty space. Need to go shopping? Fake a full fridge -- and save energy -- by putting a few pitchers and bowls of water on the shelves.