by Barbara Quinn
Burned out incandescent bulbs in the Castaic Lake Pressure Control Structure
weren’t just a nuisance for the Metropolitan Water District, which is
responsible for the California Aqueduct that transports water from the Sacramento-area
Oroville Dam to some 17 million people in Southern California. Operators needed
dependable light to operate machinery and process controls – and with
up to a third of the facility’s 500 incandescent lamps down at any one
time, they weren’t getting it.
The district chose LED (light-emitting diode) lamps from LEDtronics as an alternative
to its traditional incandescent lighting system. The advantages of the lamps
were compelling: a 100,000-hour lamp life, sharply reduced energy use and virtually
no labor expenses for system maintenance or bulb replacement. Simple replacement
of the incandescent bulbs with LED lamps eliminated retrofitting costs. And,
by preventing the disposal of thousands of burnt-out incandescent lights, the
LEDs eliminated a significant source of pollution.
LED technology has evolved substantially in only a few years. At its most basic,
an LED is a semiconductor diode chip mounted the reflector cup of a lead frame.
The frame is connected to electrical wires and encased in a solid epoxy lens.
Light is emitted when energy levels change in the semiconductor diode. Unlike
incandescent bulbs, which give off the full spectrum of light in a spherical
pattern, LEDs emit a focused beam of a single wavelength at a variety of angles
but in only one direction.
Early LEDs were limited to marginal uses, such as switch illuminators, but
the technology’s range of uses changed when multi-chip arrays and high-flux
LED chips were developed. Other technical advances dramatically increased LED
light output. Today’s LEDS can transmit both visible and infrared wavelengths,
with colored light determined exclusively by the semiconductor compound used
to make the LED chip.
An LED produces no heat and is virtually impervious to shock, vibration and
temperature extremes, making them almost indestructible. Also worth noting,
LEDs don’t burst; when they need replacement, their light gradually fades,
allowing time for replacement.
Expanding applications Although not yet optimal for all applications, such as
general lighting, LED technology incorporates unique characteristics that have
made it the preferred choice for some uses.
For example, a doctor with the Royal Danish Air Force burned his hand on a
hot halogen bulb that promptly burned out when a swing-arm task light above
the examination table in a medevac helicopter made the light fixture too hot
to reposition. The Danish Air Material Command immediately sought an alternative
that would provide the necessary light without the accompanying heat. LEDtronics
supplied a direct incandescent replacement that conformed to the standard European
E27 socket, allowing a simple swap-out of lamps.
In another application, blue LED lights now illuminate the Vincent Thomas Bridge
in Los Angeles. The mile-long span features 80 lamps, each one containing 360
LEDs but using only 19.5 watts of power to produce light equivalent to a 150-watt
incandescent bulb. To offset energy costs yet further, 4.5 kW solar panels,
located near the bridge, generate electricity, which is sold to the Los Angeles
Department of Water and Power.
Total lifetime costs for LED lighting compare well to incandescents needed
for the same time period. For the bridge, lifespan savings are estimated to
be $688,400, with energy savings alone of $184,000. Initial LED lamp costs have
shaken more than one potential buyer. LEDtronics website features an interactive
program that produces a direct comparison between incandescent and LED lamps
for individual projects.
Founded in 1983, LEDtronics® leads where others only follow when it comes
to designing, manufacturing and packaging state-of-the-art LEDs to meet the
world’s constantly changing lighting needs. Our inventive product line
encompasses an array of direct incandescent lamp replacement Based LEDs, low-cost
snap-in and re-lampable Panel Mount LEDs, high intensity sunlight-visible Discrete
LEDs, PCB LEDs circuit board status indicators, surface mount diodes SMT LEDs,
full-spectrum rainbow RGB LEDs, Ultraviolet (UV) and Infra-Red (IR) LEDs.
For additional information, contact LEDtronics toll free at 1-800-579-4875,
telephone 310-534-1505, fax at 310-534-1424, click here to email us
or mail at LEDtronics Inc., 23105 Kashiwa Court, Torrance, CA 90505. Visit our
website at www.LEDtronics.com.