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sell you on LED lights as a solution to high utility bills
Increasingly consumers are turning their eyes towards LED house lights as a
way to conserve electricity. But will you really achieve the greatest savings by
buying this still expensive lighting now? Or would you be better off to save
your money for the time being, or to buy other energy-efficient light bulbs, and
use the money you save in electricity to buy LED house lights down the road?LED-TV
You have most likely seen LEDs before: camping headlamps, LED Christmas tree
lights, wind-up emergency torches. How about LED house lights? If LEDs are so
efficient, why aren't manufacturers lining up to sell LED lights for the home,
and why aren't we lining up to buy them?
I wouldn't try to sell you on LED lights as a solution to high utility bills
or as the most ecologically beneficial lighting solution around. Frankly, I
think LEDs have a ways to go yet, in terms of function, durability, and economy.
There are some LED products you should consider over the next year, such as LED
Christmas lights. And you might enjoy trying out a couple of LED light bulbs, if
you're the energy-saving type. But you are going to save more money by keeping
with your current lighting, and migrating to fluorescent lights in the next year
or so. Compact fluorescent lights, or CFLs, have a payback so short that they'll
pay for themselves before LEDs have matured enough to make CFLs out of date.
LED light bulbs are more efficient than incandescent or fluorescent lighting.
The problem is that LEDs have very directed light. An incandescent light shines
over a wide area fairly evenly, while LED lights are very focused, so that the
area they directly illuminate is very bright, while the further you go from the
direct beam, the less light there is. For LED Christmas lights, that isn't a
problem; you just want some shining points of light, which LEDs do very
efficiently. But an incandescent or CFL will do a much better job of brightening
up your living room than an LED bulb in the same application. The light will be
more evenly and broadly spread, and with a warmer color.
When you see LED packaging claims of LED light output, you should be
doubtful. A number in Lumens, which indicates light brightness, is misleading
for LEDs, because of their focused beam. Lumens levels are read from a sensor
placed right underneath the light source. A household LED light bulb at 2 watts
may have the same lumens rating as a 50 watt halogen bulb, or as a 15 watt CFL,
but the LED lamp may only send a focused light directly under it to the photo
sensor, while the incandescent light and CFL will light up a much broader area,
and still give that same lumens rating for the area immediately beneath the
bulb. This may be the source of a frequent negative comment among LED owners,
such as: "The packaging claims this 2-watt LED bulb has the same light output as
a 50-watt incandescent bulb but it feels more like a 25-watt incandescent if you
ask me."
When it comes to halogen lights, they are only as efficient as incandescent
lights, so the same efficiency considerations apply here. But since halogen
lights are typically much more direct than incandescent bulbs, LED lights that
are designed to replace halogen lights are both more efficient than the halogens
they replace, and work well for the direct light that halogen bulbs provide. You
can find LED replacement bulbs for the most common halogen fixtures such as GU10
and MR13, and this may be a good place to start the switchover.
LED house light designers work around the issue of the narrow beam of a
single LED, by building household LED light bulbs that are a collection of
individual LEDs, with each diode aimed at a different angle, so that a wider
area is highly illuminated. This increases the area of full light coverage of an
LED light. However very few such bulbs provide the breadth of area coverage of
existing incandescent bulbs or CFLs and at the same time are bright enough |
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