When cooking a casserole or a yummy chocolate souffle, use ceramic or glass baking dishes; these materials outperform metal and will allow you to lower the temperature of the oven by 25 degrees Fahrenheit. Lower heat means less energy.
Keep the blustery cold air outdoors by stopping drafts at windows and doors. Place a draft dodger -- a long fabric tube -- along the edges where cold seeps inside to stop it in its tracks. For smaller windows, you can make your own dodger: Just fill a large sock -- like an athletic sock -- with pebbles, tie a knot at the end, and put in place.