Here are some simple things you can do to start saving energy today.
Your refrigerator works best when the coils on the back of it are clean. The coils are essentially heat exchangers and when they are dusty and dirty they don't work as well as they could. This will cost you more money than normal, because dirty coils will make the refrigerator work harder to keep your perishables cold. You should clean them at least twice a year.
If you are lucky enough to have a dishwasher (not your spouse - the mechanical kind!), then you can use your dishwasher as the manufacturer directed: wash full loads. Washing a full load of dishes in the dishwasher actually uses less water than washing them in the sink or washing two half-full loads.
There are two things you can do to make your home cleaner, quieter, more comfortable, and less costly to heat and cool; caulking and weather stripping. Caulking is basically sealing any cracks or holes around drywall joints, outlets, vents, window and door frames, and wall penetrations. Weather stripping is the gaskets that seal your doors and windows when they are closed. Good weather stripping significantly reduces air leaking into or out of your house. It also makes your house quieter, cleaner (less dirt coming in through the leaks), and less drafty all of which equate to a more comfortable home.
Insulate the hot and cold water lines going into and coming out of your water heater for at least the first five feet of pipe coming out of the tank. This easy-to-do measure reduces the energy use of your hot water heater by reducing the conduction that occurs from the hot outlet pipe. It saves energy on the cold water side by reducing heat loss that occurs when "thermosiphoning" causes hot water to rise into the cold water line. If you have a recirculating pump on your hot water heater, insulate as much of your hot water piping as possible since this type of system keeps the hot water pipes hot throughout their length at all times.
When retaining existing hardwired fixtures, almost all of the incandescent light bulbs can be replaced with screw-in Compact Fluorescent Light bulbs (CFL). These lights last seven times longer than incandescent light bulbs and use one-fourth the energy to produce the same amount of light, with the added benefit of producing less heat. New technology allows these bulbs to produce a warm, pleasant light compared to old-style fluorescents. They are direct screw-in replacements for your existing incandescent bulbs. Most manufacturers have recommendations on their packaging on what wattage you should buy to replace your current incandescent bulb. So before you purchase CFLs be sure to determine the wattage of incandescent light bulbs you are replacing.