Controls and making good use of daylighting also reduce lighting energy needs. Let the sun shine in Using daylight effectively reduces electric lighting needs during daylight hours.
Daylight is the least expensive and most pleasing light source.
Light-colored interiors and window trim and good window placement make the most of natural light. The simplest way to save lighting energy is to turn lights off when you're not using them. Dimmers cut energy use by reducing power to the lamp. They give you control over how much light you need, when. A variety of new compact fluorescent lamps produce more light for a given amount of energy, compared to standard incandescent bulbs.