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LEDs, The New
Option
For decades the choice came down to an incandescent bulb or a
fluorescent. Even with the relatively recent introduction of
CFLs (Compact Fluorescent Lights), incandescents almost always
won. CFLs are much more expensive and still don't give off the
same spectrum of natural-looking light that 'ordinary' bulbs
come much closer to.
Enter LEDs.
Light emitting diodes have been used for over 40 years, first
making their commercial appearance in watches and small clocks.
But for almost that same length of time, they gave off too
little light and of limited color to be useful for home
illumination. No one could read or cook by a dim red light.
But LED bulbs have come a long way in recent years. While still
much more expensive than an incandescent bulb, they have
overcome many of the disadvantages of fluorescents. They
produce bright, natural-spectrum white light that can
illuminate a medium-sized area with one bulb. Actually the
bulbs are made of multiple LEDs in one enclosure.
And, not the least consideration, they last practically
forever. A LED bulb can burn for over 50,000 hours. Some are
rated at 60,000 hours. Even if in use for as much as 10 hours
per day (4 hours/day is closer to average), that works out to
almost 14 years of use.
Add up all the money spent on incandescents - which last from
750-1,000 hours - and the total savings is substantial. If a
75-watt bulb costs $1 and an LED bulb costs $50, most will opt
for the incandescent. But if the LED lasts 50 times longer, you
break even. That doesn't even include the time spent picking up
bulbs, changing them and so forth.
Apart from the initial outlay costs, the difference in
electricity use is equally dramatic, but in the LED's favor.
Keep in mind that the standard label on an incandescent is how
much power it consumes, not how much light it puts out. A
60-watt incandescent bulb puts out somewhat less than 900
lumens.
A LED bulb costing roughly $50 is available that is the
equivalent of a 60-watt incandescent in terms of the light
given off. Yet, it consumes only 2 watts of electricity.
Multiply that electricity savings by 4 hours per day over 10
years and the cost savings will far outweigh the cost of the
LED bulb. At 10 cents/kWh, the total savings over 10 years is
about $350. So, the bulb will pay for itself in about 18
months.
At the same time, a LED bulb runs cooler so there's no danger
of burning as so often happens with incandescents. A 100-watt
bulb placed in a socket designed for a 40-watt will burn the
covering plastic shade in a matter of hours or less. Also, how
many times have you singed your skin when touching an ordinary
bulb? That doesn't happen with LED bulbs.
The color spectrum of LED bulbs is also superior. While
incandescents do a good job or providing a reasonable emulation
of natural sunlight, LEDs are far better. Incandescents are
somewhat yellow, LEDs are white and much closer to the color
temperature of natural daylight. And, unlike fluorescent bulbs,
LEDs contain no mercury, which is hazardous if the bulb
breaks.
Still LEDs have some drawbacks, apart from the higher cost.
They don't currently put out as much light per bulb as a single
incandescent so it may require more than one for particular
lighting applications. They light a little less than CFL
bulbs.
Since LEDs are more directional, they'll do better in reading
lamps, recessed ceiling lamps and other such applications than
as general ambient light. But where a long-lasting and/or
always-on bulb is needed they can be very cost-effective.
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