Replace incandescent bulbs with compact fluorescents (CFLs). Compact fluorescents use four times less energy, and last eight times longer (8,000h instead of 1,000h) than incandescent light bulbs. For example, a typical 75W incandescent bulb can be replaced by an 18W compact fluorescent. The compact fluorescent will be more expensive to buy, but you will need to replace it eight times less often and it will use less electricity, which often makes it the biggest electricity saver in your house.  At a minimum, we recommend replacing the bulbs in all lamps that are used for 30 minutes a day or more.