Lighting and Daylighting

Lighting adds to the aesthetics and usability of any home. It is also "power hungry," accounting for nearly 15 percent of the average home's electric bill. Fortunately, homeowners can take easy, relatively inexpensive steps to reduce the cost and energy consumed in lighting their home. Using energy-efficient lights, fixtures, and controls can have a significant and favorable impact on home lighting costs. New lighting technology can provide energy savings of 50 to 75 percent.

A variety of lighting product choices are available to the homeowner:

Incandescent

The oldest and most common lighting product is the incandescent lamp or light bulb. It accounts for about 85 percent of indoor home lighting. Incandescent lamps emit light when electricity flows through and heats a metal tungsten filament. Incandescent lamps are popular due to their low cost, warm light, and excellent color rendition. They light up instantly and can be used with a dimmer switch. However, when compared to other lighting sources, they have a short life, generate more heat, and produce less light per watt of energy.

Fluorescent

Fluorescent lamps produce light when an electric current passes through mercury and inert gasses. They require a ballast to regulate the current and provide the high voltage pulse needed for start-up. The use of electronic ballasts to replace standard and electromagnetic ballasts has increased the energy efficiency and eliminated the flicker and noise of this type of lighting. Fluorescent lamps use only 25 to 30 percent of the energy consumed by incandescent lamps to provide the same amount of illumination. Fluorescent lamps also last about 10 times longer than incandescent lamps. These benefits and improvements in the color rendition and temperature of fluorescent lamps have expanded the applications for this type of lighting.

Compact Fluorescent Lamps (CFLs)

Compact fluorescent lamps combine the energy efficiency of fluorescent lamps with the convenience and popularity of incandescent lamps. CFLs can replace incandescent lamps with three to four times the wattage, saving 75 percent of lighting energy. While CFLs can cost 3 to 10 times more than incandescent lamps, they last 6 to 15 times longer. This longer life combined with significantly lower energy use more than offsets the higher initial price of CFLs. These lamps work much like a standard fluorescent and contain a ballast and gas filled tube. They are designed to screw into a lighting fixture just like standard incandescent lamps. Most CFLs are designed for indoor use, although several outside models can function in colder temperatures. CFLs are especially beneficial in areas where lights are left on for long periods of time. Because of their long operating life, CFLs are ideal for hard-to-reach areas. Learn more.

Solid State Lighting

The next frontier of lighting technology is solid state lighting (SSL) utilizing light-emitting diodes (LEDs) or organic light-emitting diodes (OLEDs).

• LEDs have been around since the 1960s, but they are just now reaching the levels of luminous output and power that open the door to more applications. For example, today's commercially available LEDs offer energy efficiency, maintenance savings, impact resistance, durability, and other benefits for traffic signals, exit signs, and other specialty applications. White LEDs are approaching performance levels that make them attractive for use in automobiles, aircraft, and elevators. For most general illumination applications, however, current LEDs cannot yet compete with traditional sources in performance or cost.
• OLEDs are based on organic (carbon based) materials. In contrast to LEDs, which are small point sources, OLEDs are made in sheets which provide a diffuse area light source. OLED technology is developing rapidly and is increasingly used in display applications such as cell phones and PDA screens. However, OLEDs are still some years away from becoming a practical general illumination source. Additional advancements are needed in light output, color, efficiency, cost, and lifetime.

More research is needed to increase the efficiency and decrease the cost of SSL technologies. Leading this research is a Solid State Lighting partnership between the U.S. Department of Energy (DOE) and the Next Generation Lighting Industry Alliance (NGLIA). The Department of Energy's solid-state lighting R&D plan spans 2000 through 2020. It includes core technology research, product development, and commercialization efforts focused on SSL.

Daylighting

Daylighting is the use of windows and skylights to bring more natural light into a home. It is the perfect complement to energy-efficient home lighting. Daylighting reduces energy demand for interior lighting. Homes that actively incorporate daylighting will be less reliant on artificial indoor lighting during the day and will enjoy quality, natural light. Maximum benefits from daylighting are best obtained when it is integrated into the design and siting of a new home. It can also be used during the renovation of an existing home.

Learn More

Look for more information about new lighting technology, including the types of lighting available and energy saving lighting controls, in the Consumer's Guide to Energy Efficiency and Renewable Energy.

An additional source of information on energy-efficient lighting products can be found at the ENERGY STAR^® program. ENERGY STAR, a joint program of the U.S. Environmental Protection Agency and the U.S. Department of Energy, helps consumers save money and protect the environment through energy-efficient products and practices. The ENERGY STAR website includes useful information about lighting.

 

 

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