Heavy or insulated drapes can help prevent heat loss through windows at night, while south-facing windows can help heat your house during winter days. Improperly installed insulation around bathtubs, pipes, ducts, and in the attic may also be raising your energy costs. To find out where your house needs a little extra caulking, you can have a blower door test done. It's an easy and effective way to gage your home's energy efficiency. Contact your energy provider to see if they offer blower door testing.
Many appliances commonly used in the U.S. are very inefficient.
Refrigerators and washing machines top the list. Most refrigerators are designed ineffectively, especially the frost-free ones. To begin with, the compressor is located in the bottom so that the heat rises up through the refrigerator, which makes the machine have to work even harder to keep your food cold. To stay frost-free, freezers actually have heating elements. It sounds counter-intuitive, but you're actually heating the walls of the space you're trying to keep cold.