We found the CREE (LLF) LR4 11W LED Recessed Light online listed for $137 retail. It’s one of many new recessed LED brands that are beginning to unseat airtight CFLs as the light source of choice-primarily at the high end of the new and retrofit market-but costs are dropping. Available at
www.discoverylighting.com
DIMMERS WITH AN ATTITUDE
Lutron’s energy-saving dimmers offer incentive to reduce lighting use for both the converted homeowner and the prudent landlord.
www.lutron.com
Virtue Is It’s Own Reward.
These “Eco-minder” dimmers include a green LED light that turns on when energy savings reach 15%.
Trust, But Verify.
The landlord-friendly “Eco-dim” takes charge of the situation, automatically dimming the circuit by a minimum of 15%.
Your Time is Up.
Eco-timers automatically shut off lights or bathroom fans after a set amount of time.
Sensors with Common Sense.
Wired and wireless sensors offer a middle ground between automatic saving and voluntary reduction, turning off lights when you leave the room.
SOME LED FIXTURES ARE MORE EQUAL THAN OTHERS
Would it surprise you to learn that some LEDs are less efficient than incandescent light bulbs?
The DOE CALiPER program tested 26 SSL products. The white line indicates the point where lamp is producing 70% of its initial output, and the descending white curve represents where a product’s lumen output should be when it hits 50,000 hours. As you can see, five products essentially failed-with light output dropping off precipitously and early.
That’s right. The Department of Energy has been testing new lighting products through its CALiPER program, which began in 2007. They’ve found that LEDs (also referred to as solid-state lighting, or SSL) don’t always perform as advertised. In fairness, the same can be said of CFLs, but for now, let’s focus on the LED problem.
Even SSL brands that look identical can perform differently, the researchers note. In most cases, problem brands tend to handle heat badly. In other words, they become overheated and damaged. Also, LEDs tend to start losing luminance right off the shelf. In better made brands, that loss is very slow. In others, it’s rapid.
They note that while some lamps maintain light output well over their first 6,000 hours, others drop off within 1,000 hours. Some demonstrate “significant color shift” in the first 6,000 hours. Their conclusion: “No generalizable patterns can be observed.” As is typical of government studies in this age of deregulation, CALiPER has been reluctant to identify which brands to avoid. We’d like to see the kid gloves come off.
BETTER LEDS IN THE PIPELINE?
One obstacle to LED efficiency has been maximizing and stabilizing their light output. Nichia Corp. says it has developed high power white light LEDs that have a luminous flux of 1913 lumens and a luminous efficacy of 140 lumens per watt at 1 amp. This enables it to emit more light than a typical 20W fluorescent bulb. The researchers also note that they have “drastically improved the lumen maintenance at higher junction temperatures.” Presumably, that should stabilize the light output and make early failure less likely.
www.nichia.com
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02.2011
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