LED has advantages but also drawbacks
LED light bulbs contain no mercury, & they offer other advantages over compact fluorescent light bulbs. LED light bulbs turn on instantly, last much longer & are more energy efficient. Their lifetime is not affected by frequent turning on & off, so they are suitable for lighting fixtures that don't stay on long -- or conversely, for lighting fixtures that stay on so long that the additional energy efficiency is significant. LED light bulbs are also less apt to break.
Reviews say that in the long run, the high cost ($20 to $80) of screw-in LED light bulbs will pay for itself in savings on electricity. However, they were unable to find any compelling proof that the rated life is exactly the specificated for every bulb by the manufacturer. It is one thing to bet on a compact fluorescent light bulb that costs $2 to $4, yet another to wonder if an $80 light bulb will last its rated life -- because light bulb ratings are based on ideal conditions of temperature & humidity.
The least expensive LED light bulb at present for everyday use is the EcoSmart LED A19 (*Est. $20), a 40-watt equivalent light bulb that is sold exclusively at Home Depot. We have seen no professional reviews for it, but around 30 owners post at HomeDepot.com and give it a solid rating overall. Most are pleased, but some drawbacks are noted. They saw comments that the EcoSmart LED A19 is liable to throwing off radio-frequency interference, which may cause static on nearby radios. One complains that the bulb burned out in its first month of use. Another says the bulb is directional.
Until recently, LED light bulbs designed to cast light in all directions (for use in a regular table lamp) did not put out lumens to make this realistic except for dim "atmospheric" background lighting. Some owners say the light from an LED is cold and bluish. Owners say they are dimmer than expected, even when used in a light fixture that takes advantage of their directional beam (usually a 60- to 100-degree angle). Led light manufacturers are making efforts to produce LED lights that are both affordable and offer light equivalent to that produced by incandescent light bulbs, as well as a few have cropped up that get positive reviews. Prices have begun to come down, also, making LEDs an up-and-coming contender for standard household use.
EarthLED also produces the EvoLux and ZetaLux models, which have multiple LEDs in a single casing. The EvoLux (*Est. $50) claims to deliver light equal to that of a 100-watt incandescent, while the ZetaLux (*Est. $40) claims to be equivalent to a 50- or 60-watt incandescent. The ZetaLux is rated for 50,000 hours. The EvoLux has fewer than 10 owner-written reviews on GreenOptions.com, but does maintain a rating of 4 stars out of 5, earning the sixth position in the website's overall light bulb rankings. Several owners say the brightness of the EvoLux is comparable to light produced by equivalent CFLs, but the light is very directionally focused. The ZetaLux has even less feedback, but what is there is mostly positive, earning this bulb an overall rating of 4.5 stars out of 5. Owners say the light quality is fine and the instant-on is a and over CFLs, but like the EvoLux the light focuses in one direction.
GreenOptions.com, an environmentally focused social network that allows consumers to rate and review environmentally friendly products, also offers a choice of reviews for LED light bulbs, but the volume of reviews is slim. Still, the EarthLED DesignoLux CL-3 LED (*Est. $30) light bulb earns the top rating among all types of light bulbs reviewed on the net site, with an average rating of 4.5 stars out of 5, based on over 10 owner-written reviews. Owners say the EarthLED DesignoLux CL-3 looks like a regular light bulb and produces soft, warm light -- using 3 watts to replace 30 watts -- that it is indistinguishable from an incandescent. The EarthLED DesignoLux CL-3 is rated to last for 50,000 hours, and EarthLED offers a three-year replacement warranty. Several owners do note that the DesignoLux CL-3 is most appropriate for smaller spaces, such as bathrooms, that don't need lots of light.
Several companies have recently announced LED light bulbs that objective to overcome the directional limitation of current LED bulbs, which perhaps will move them further in to the mainstream. For example, the GE Energy Clever LED bulb is an omnidirectional 9-watt LED that produces light equivalent to a 40-watt incandescent. The GE Energy Clever LED, to be released in 2011, has a plastic casing surrounding the bulb that looks like a series of fins, designed to help cast light all around the bulb in lieu of in one direction, as most current LEDs do. The GE Energy Clever LED has a life span rating of 25,000 hours. Osram Sylvania and Philips have announced 60-watt equivalent LED bulbs that are scheduled to be available in 2011.
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