Although
the origin of Light Emitting Diode or LED technology can be traced back to
1927, it did not enter the commercial arena until much later. This was largely
due to its high production cost; it is, however, rapidly gaining ground in more
recent times. With the increasing demand for greener, more energy-efficient
products, as well as the worldwide environmental strain on energy resources, is
LED technology the answer to our lighting needs? What does the future hold for
LED technology and does it have what it takes to overpower the traditional
light bulb, which was perhaps the most life‐changing invention in human
history?
LED
lights are likely the most environmentally friendly lighting options available
in the current scenario. So what makes it the leading choice in industrial,
architectural, and horticultural applications around the world? LEDs last as
much as 20 times longer than other lighting sources, and therefore don’t need
to be replaced as often. This reduces the impact of manufacturing, packaging,
and shipping. LEDs are also designed to provide more than a decade of near
maintenance-free service. Less servicing also reduces environmental impact.
Additionally, LEDs consume much less
energy than incandescent and high-intensity discharge (HID) lights. LED
lights use only 2–17 watts of electricity, which is 25%–80% less energy than
standard lighting systems. And while compact fluorescent lights are also
energy-efficient, LEDs burn even less energy. LEDs contain no mercury, unlike
their HID counterparts, whose mercury-laden remnants can seep into the water
supply and adversely affect sea life, and those who consume it.
According to the U.S. Department of Energy, “Widespread use of LED lighting
has the greatest potential impact on energy savings in the United States. By
2027, widespread use of LEDs could save about 348 terawatt hours (compared to
no LED use) of electricity: This is the equivalent annual electrical output of
44 large electric power plants (1000 megawatts each), and a total savings of
more than $30 billion at today’s electricity prices.”
The electrical maintenance required for lighting
systems in public buildings that receive harsh and prolonged use, sometimes 24
hours a day, 365 days of the year, is overwhelming. In
public building management, time is money, and because changing LED fixtures
happens far less often than traditional lighting, public building management
will have to spend less time on the ladder changing bulbs. LED lighting
contributes to energy savings and sustainability by improving working
conditions through deliberately directed light and by reducing the energy
needed to power lighting fixtures.
A groundbreaking advancement in this area
came to the forefront when Isamu Akasaki, Professor at Meijo University,
Hiroshi Amano, Professor at Nagoya University, and Shuki Nakahmura, a
Japanese-born Professor currently at the University of California, Santa Barbara
won the Nobel Prize in Physics earlier this month for inventing the world’s
first blue light-emitting diodes (LEDs).
While red and green LEDs had been around for some time, the elusive
blue LED represented a long-standing challenge for researchers in both academia
and industry. Without this critical last piece, scientists were unable to
produce white light from LEDs, as all three colors needed to be mixed together
for this to happen.
The white LED lamps that resulted from this invention emit very bright
white light and are superior in terms of energy efficiency and lifespan when
compared with incandescent and fluorescent bulbs. LEDs can last some
100,000 hours, whereas incandescent bulbs typically last only about 1,000.
“With 20% of the world’s electricity used for lighting, it’s been calculated
that optimal use of LED lighting could reduce this to 4%,” said Dr. Frances Saunders, President of the Institute of Physics. “This is
physics research that is having a direct impact on the grandest of scales,
helping protect our environment, as well as turning up in our everyday
electronic gadgets.”
What’s more, these LED lamps have the potential to improve the quality
of life for more than 1.5 billion people in
the world that do not have access to electricity grids. Since LEDs require very
little energy input, they can run on cheap local solar power.
Steven DenBaars, a research scientist at UC Santa Barbara, has been working on
LED lights for 20 years. In his laboratory, he is already onto the next big
thing: Replacing a substantial portion of indoor lights, and the archaic bulb
and socket infrastructure on which they depend, with lasers.
According to DenBaars, the working of lasers is very similar to an LED
lightbulb. “It’s the same materials, but you put two mirrors on either side of
the LED and it breaks into a laser. Once you get reflection back and forth, you
get an amplification effect, and it goes from regular emission to stimulated
emission.”
Simply replacing the light emitting diodes in a
typical LED bulb with a laser diode wouldn’t work. This hypothetical laser
light bulb would catch on fire from all the waste heat it would generate, not
to mention an ungodly amount of light, more than enough to blind anyone who
looked at it. Rather, DenBaars imagines using just a handful of tiny but
powerful lasers, and then redirecting their light into fiber-optic cables and
other types of light-transmitting plastic that could take that light and evenly
distribute it into a warm, diffuse glow.
BMW’s “hybrid supercar,” the i8, uses headlights that are the latest
example of laser-based lighting technology. Like all lasers re-appropriated for
conventional illumination, blue laser diodes were aimed at a phosphor that
transforms the blue laser light into more diffused white light. The result is
headlights with such a long working life that they could “easily outlive the
automobile” in which they’re installed, notes IEEE Spectrum.
Laser lights could solve the problem of how to bridge
the gap between traditional light sockets and more radical configurations of
new lighting technologies. With just a few point sources of laser light
installed in a building, their illumination can be redirected throughout a
structure via plastic fiber-optic cables that could run along ceilings and
around corners, just as the cable company runs its wires into buildings and
through rooms without having to tear holes in walls or interface with the
electrical system of a building. “Rather than route the electricity to the bulb
you can route the light to the sources. LEDs let you do that too, but lasers
would take it a couple steps further,” says DenBaars.
LEDs are helping change the way we light up our world, facilitating the
development of environmentally friendly, energy-efficient light sources that
offer a dramatic improvement from the incandescent bulbs pioneered at the
beginning of the 20th century.
For our
relevant BCC Research report on LED, visit the following link: