Artificial lighting consumes almost 15 percent of a household's electricity use. Lighting fixtures may be the easiest items to modify to save energy. According to ENERGY STAR, replacing your home’s five most-frequently-used light fixtures, or the bulbs in them, with high efficiency lights can save you as much as $70 a year in energy costs. ENERGY STAR-qualified lighting also uses 75 percent less energy, generates 70 percent less heat, and lasts up to 10 times longer than standard lighting.

• Turn off overhead lights and lamps when you leave a room.
• Buy CFLs to replace incandescent light bulbs in frequently-used fixtures around your home. CFLs use up to 75 percent less energy. See our Lighting Calculator to compare. 
• Consider “daylighting” – open blinds and curtains on energy-efficient, north and south-facing windows to allow sunlight rather than artificial lighting to produce light in a room.
• Use a timer to turn lights on and off, especially outside security lights, at pre-determined times.
• Consider an ENERGY STAR-qualified outdoor fixture, with a CFL if possible, for outside security lights and porch lamps that often remain on for long, consecutive hours. Try motion-detector lighting for outside lights, if possible.
• Perform a home energy audit of your lights.