Close window blinds at night to prevent lights from shining outward. Turning off a few lights makes a big difference in conservation. Buy Design Use lights that have shields on their tops or sides so that they illuminate only where they're supposed to. Lights without shields, such as floodlights or globes, shine upward and sideways. Most exterior lights can be outfitted with shields.
Fluorescent lighting is about four times as efficient as incandescent lighting.
Though fluorescents are most popular indoors, their outdoor use is increasing. Be Clean Better housecleaning lessens the inclination to overlight. Dirt that builds up on room walls can reduce their reflectability, and dust that collects on lamps and fixtures can dull the light shining through. Together dirt and dust can reduce total illumination as much as 50 percent. If you use yard lights, consider ones that will minimize your contribution to light pollution.