DRIVING THE INDUSTRY SINCE 1991
affecting the industry. Manufacturers started developing LEDs for installation at the factory level, along with after-factory retrofit kits, and the increased visibility has improved reaction times within public transportation. “In the early days, 1999, when we set out to build the first LED loading lights for school bus- es, we were searching for an alternative to strobe lights minus the power pack and running wires from front to rear of the bus (ease of installation) and still obtain the rapid flash effect,” said Bran- don Billingsley, president and owner of Heavy Duty Bus Parts, Inc. “What resulted was in addition to rapid flash, which is proven for added attention, the various benefits of LEDs included lower power consumption and longer product life, which reduces maintenance, and an all-around winner other than the high cost back then. Te company recently introduced sur-
face-mount diodes, or SMD, technology that Billingsley called “an even more robust product” that is achieved at almost cost parity to halogen or incandescent with fewer LEDs. Tis, he add- ed creates “a very reliable, high-visibility lamp, which is affordable for all practice purposes.”
LED MANUFACTURERS OFFER EXTENDED WARRANTIES, LONGER LIFE CYCLES
In independent research studies, the reaction
time for the average driver is at least 250 mil- liseconds faster at an LED-operated stop, turn or tail light. Tis translates to a shorter stopping distance depending on vehicle speed and weight. With increased illumination, state regula-
tions allow a certain percentage of LED burn out, which increases the life cycle of the light. With warranty periods of up to five years, fleets can monitor failures and ship affected lights back to the manufacturer for processing. “Not only have prices dropped, but LED
manufacturers have also decreased the number of diodes, reducing failure rates while increas- ing illumination,” said Doug Revelle, manager of customer support at Florida Transportation Systems. “In Florida there is a 50 percent allowable burn-out rate, increasing service life. And since warranty is covered up to five years, fleet operators need to monitor bus LED light- ing and manage claims when required.”
FUTURE LOOKS BRIGHT WITH INDUSTRY ACCEPTANCE, INCREASED SALES
With the benefits of LED lights circulating
throughout the transportation industry, sales figures reflect the rising popularity. According to LEDs Magazine, the strongest segment for growth in automotive is for headlamps, which of course are utilized by school buses. LED head- lamps are expected to make up 38 percent of the
automotive revenues by 2016, up from 10 per- cent in 2011, the magazine wrote last Septem- ber. Daytime running lights made up the largest portion of the automotive market in 2011, at 26 percent. Automotive LEDs are expected to grow by 6.6 percent CAGR over 2012-2016. Te environmental impact has been doc- umented as well with less failed parts going into waste dumps. Researchers from the U.S. Department of Energy’s Pacific Northwest National Laboratory and from the United Kingdom published a first-of-its-kind report last September on the environmental effect of LED manufacturing and usage. It claimed that LEDs have a slight edge over compact fluorescent lights, or CFLs, and incandes- cent bulbs. But, the report continued, the carbon footprint of LEDs in comparison to traditional lighting will only decrease over time. “Te light-emit- ting diode lamp is a rapidly evolving technology that, while already energy efficient, will become even more so in just a few short years,” said Marc Ledbetter, who manages PNNL’s solid-state lighting testing, analysis and deployment efforts. “Our comprehensive analysis indicates technological advancements in the near future will help people who use these lamps to keep shrinking their environmental footprints.” Fifteen different impacts were considered
when evaluating environmental footprints, in- cluding the potential to increase global warm- ing, use land formerly available to wildlife, generate waste and pollute water, soil and air. Te researchers found that both LEDs and
CFLs are “substantially more environmentally friendly” than incandescent lights. Tey reported that incandescent light bulbs consumed 60 watts of electricity, while the LED model used just 12.5 watts and the representative CFL only used 15 watts to create the about same amount of light. “By using more energy to create light,
incandescent bulbs also use more of the natural resources needed to generate the electricity that powers them,” Ledbetter said. “Regardless of whether consumers use LEDs or CFLs, this analysis shows we could reduce the environ- mental impact of lighting by three to 10 times if we choose more efficient bulbs instead of incandescent lights.”
£ LED lights burn brighter but last longer, which increases safety and cuts costs, compared to traditional incandescents.
How Different Bulbs Work Incandescent light bulbs
produce light when an electric current runs through a wire inside the bulb’s glass globe. The current causes the wire to heat up and glow.
Light-emitting diodes, or LEDs, generate light when electricity flows through an electronic component called a diode. Compact fluorescent lamps, or CFLs, emit light when electricity excites a mix of gases inside the bulb, creating invisible ultraviolet light that is absorbed by the bulb’s fluorescent coating and trans- formed into visible light.
Source: U.S. Department of Energy’s Pacific Northwest National Laboratory
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