If you've committed to replacing your incandescent lightbulbs with compact fluorescent...

Energy efficiency is all about bang for the buck and a boon for the environment. Systems or appliances are called energy efficient if they use less electricity, fuel, or other power to perform the same function that conventional ones do. For example, a new refrigerator, featuring better insulation and a top-of-the-line compressor, won't have to work as hard to keep your food cold, or use as much power, as a ten year old fridge would-it's an energy efficient model. The more efficient an appliance is, the more power, and money, it will save.

Many homeowners know very little about their heating and cooling equipment-until something goes...