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: