Look for this sticker on energy-efficient lighting at local retailers.
Learning how your home uses energy is the first step to saving. Start saving today by using our Home Energy Survey to understand your energy use.
Switch the Switch: Replace your light switches with motion or occupancy sensors, and you’ll be saving both time and energy. Or set timers that “remember” when to turn off.
Light emitting diodes (LEDs), also known as “solid-state” devices, are an emerging technology with significant potential for energy savings and longevity. LEDs have already become the standard in many low-energy applications, such as washer/dryer indicators, cell phones, bicycle lights, and holiday lights. In the realm of higher energy applications, they're making inroads into the retail, grocery, and restaurant sectors for spotlighting merchandise and food. LEDs are also used in high energy outdoor applications such as street lighting, parking lots, traffic signals, building façades, and accent lighting. LEDs are fundamentally different from incandescent or fluorescent bulbs. They're made from materials such as silicon and nickel in a process similar to that used for manufacturing computer chips. LED lights offer longevity, durability, and efficiency. Today they come in a wide range of colors including white. Modern LEDs can last 7-15 times longer than CFLs, and are 30-66% more efficient—some LED table lamps use only 5 watts. Screw-in LED bulbs are available in various sizes, although costly at $40-$60 per bulb.
LEDs have been introduced in the last few years for household lighting applications. They're great replacements for halogens in spot light applications, such as recessed ceiling fixtures in kitchen and living room. While typical costs for CFLs is $5-$10 for a pack of four bulbs, depending on the wattage, LEDs can cost between $20-$50 per bulb and provide 7-15 times greater life. Both lighting technologies are available for dimmer-controlled fixtures, table lamps, torchieres, and wall sconces, as well as outdoor fixtures.
Efficacy is the lighting industry’s measure for energy efficiency. It measures how much light a source emits (lumens) per electric energy it consumes (watts). The higher the efficacy, the more efficient the bulb. A typical incandescent has an efficacy of 7-17 lumens per watt, while CFLs and LEDs today have efficacies of 30-90 lumens per watt. However, while the potential for efficacy improvements of CFLs have matured, LEDs have the additional potential to exceed 120 lumens per watt in the future.
Many CFL package labels report a “wattage equivalent” compared to incandescents, but these are imprecise and create confusion. For example two CFL products may both report equivalency to a 100-watt incandescent bulb, but one product is actually a 14-watt CFL while another product is a 23-watt CFL. The real measure of light output is called lumens. A typical 100-watt incandescent bulb produces 1,600-1,800 lumens, while a typical 60-watt incandescent bulb produces 700-800 lumens. Because CFLs and LEDs are more efficient, or “efficacious”, they produce the same amount of lumens with lower wattage bulbs.
When a light is on, the color appearance of the bulb is called the color temperature. It's measured in degrees Kelvin (K). Warmer color temperatures (red, orange, yellow) range from 2,700 K - 3,500 K. At the store, these bulbs are typically labeled as “warm whites." Cooler colors such as green and blue, have higher color temperatures from 3,700 K - 5,000 K. These bulbs are typically labeled as “cool whites." Fluorescents also produce colder whites with lots of blue at color temperatures from 5,000 K - 7,500 K. Natural sunlight is about 5,500 K during midday and about 10,000-12,000 K at twilight. The human eye is more sensitive to blue light, and higher color temperatures improve visual acuity for detail oriented tasks. Use higher color temperature lights in garages, sheds, kitchens, and studies. Use warmer color temperature lights in living rooms, bedrooms, dining rooms, and bathrooms.
Bulb life isn't usually reported on lighting products packaging, but is important to consider when choosing between different options. The longer the bulb life, the fewer replacement bulbs you'll need to buy over a given period of time. Incandescent lights have lifetimes of 1,000-4,000 hours while CFLs have lifetimes of 6,000-15,000 hours. LEDs have the longest life, typically 30,000 hours for screw-ins and 50,000 for fixtures.
Turn off any unecessary lights between 11 a.m. to 6 p.m. on Reduce Your Use days and you may earn a bill credit. Sign up for alerts or learn more.
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