Increasing your lighting efficiency is one of the fastest ways to decrease your energy bills. ENERGY STAR-qualified LEDs (light-emitting diodes) can last more than 25,000 hours, using 80 percent less energy than incandescent bulbs. That's about three years if left on for 24 hours a day, seven days a week.
Replacing 15 inefficient incandescent bulbs in your home with energy-saving bulbs could save you about $50 per year.
Replace old incandescent bulbs with ENERGY STAR-qualified bulbs, and consider purchasing ENERGY STAR-qualified fixtures.
Use task lighting; instead of brightly lighting an entire room, focus the light where you need it. For example, use fluorescent under-cabinet lighting for kitchen sinks and countertops under cabinets.
Consider three-way lamps; they make it easier to keep lighting levels low when brighter light is not necessary.
Keep curtains or shades open to use daylighting instead of turning on lights. For more privacy, use light-colored, loose-weave curtains to allow daylight into the room.
Decorate with lighter colors that reflect daylight.
For spot lighting, consider CFLs with reflectors. The lamps range in wattage from 13-watt to 32-watt and provide a very directed light using a reflector and lens system.
Many homeowners use outdoor lighting for decoration and security. When shopping for outdoor lights, you will find a variety of products, from low-voltage pathway lighting to high-pressure sodium floodlights. Look for LED products such as pathway lights, step lights, and porch lights.
Source (click to view): U.S. Department of Energy, Energy Saver Guide