It should be noted that the general LED lighting market represents around 57% of the total LED market of $25.9bn projected for 2018. The others being signage, automotive lighting, mobile devices, backlighting in displays, monitors and other.
General lighting LED applications continue to gain traction in both commercial and residential markets, they are further accelerating growth.
According to LEDinside:
“Phenomenal growth was seen in the high lumen LED lighting systems for commercial use. This is because the LED lighting for household use is still too expensive for most consumers.
“Backed by its long-term benefits, energy-saving and environment-friendly attributes, and its relevant tax reductions, there will be a substantial increase in the use of LED lighting in commercial spaces such as the parking lot, office space, factory facility, and warehouse.
“LED lights can replace not only high pressure sodium lamps, halogen lights, incandescent bulbs, but also CFL and fluorescent lights in some areas. It is estimated that rapid growth and widespread adoption of LED commercial lighting took place in 2011, while LEDs used for household lighting did not take off until 2012.”
It is no surprise that commercial/industrial applications are leading the transition to LEDs as lighting generally represents anywhere from 25% to 40% of total energy use in commercial buildings. As these applications require long hours of high intensity light, the economic payback of the saved electrical power is relatively short-term.
Secondly, the long life of LED fixtures dramatically reduces the replacement cost of the bulbs. These replacement costs not only include the price of the bulb itself, but also the labor cost to physically replace them, which in certain applications, such as high bay lighting, is significant.
The primary driver behind the high growth rate of LED lighting is the dramatic reduction in power consumption that LED lighting offers over traditional lighting. Compared to incandescent lighting, LEDs require less than 20% of the electrical power to provide the same level of light (in lumens).
LED advantages include a lifetime orders of magnitude higher than incandescent bulbs, which dramatically reduces replacement costs. The ability to dim LEDs using the previously installed base of TRIAC dimmers is also a major benefit, especially in residential lighting. Instant turn-on eliminates the warm-up period associated with CFLs and LEDs are not sensitive to power cycling like their CFL counterparts.
Additionally, LED lighting fixtures do not contain any toxic materials to manage or dispose of, whereas CFL utilizes toxic mercury gas to operate. Lastly, LEDs enable new very low profile form factors that other technologies could not.
Nevertheless, another contributing factor driving the conversion to household LED lighting is the fact that the 40W and 60W incandescent light bulbs typically used in the majority of American homes were banned from being manufactured in the USA, or imported, at the end of 2013 (however; they can still be purchased). It should also be noted that the 75W and 100W bulbs were phased out in 2012.
The cause of their demise being primarily driven by the need for better electrical to light output efficacy demanded by the environmental protection agency (EPA). The predominant reason being to help lower electricity consumption (and, therefore, generation) due to the fact that residential household lighting accounted for roughly 14% of electrical power consumption (Source: US Energy Information Administration).
And so, the solid state LED equivalent, requiring only about one-eighth of the power to generate the equivalent amount of lumens output, has made its way into our modern world.
Cree’s selling price of its 60W LED equivalent is down to $7.97 at Home Depot. This Cree light bulb is designed to last 25,000 hours and saves 84 percent of the electrical energy when compared to the traditional incandescent counterpart.
Furthermore, and more importantly to the consumer, Cree claims that by replacing the incandescent bulbs with their LED bulbs in a home’s five most frequently used light fixtures, consumers can save an average of about $60 per year on their electric bills. So while most consumers still baulk at an $8 price for a 60W LED bulb, they cannot buy its incandescent equivalent any longer.
The good news is that competing suppliers such as Philips and Feit continue to offer special pricing incentives where the average cost for these bulbs is just under $3 each.
This sequence of evolutionary lighting changes, from the incandescent light bulb to solid state electronic equivalents, is analogous to the current migration occurring in the automotive industry with vehicle lighting.
While red LEDs have been used in taillights for over a decade, it is the changes in the car’s interior and forward illumination lighting systems which have only recently made significant strides in LED adoption rates. For example, LEDs are found in over 70% of interior indicator lights and over 45% for instrument display backlights. Contrast this with the daytime running lights (DRLs) at over 55% and headlamps at approximately 5% today.
So why is it that LED headlamps have not taken off as well as the LEDs used in the other forms of automotive LED lighting? Well, the answer is, of course, cost. The alternatives to using LEDs in the headlamp are: incandescent bulbs, halogen bulbs or HID xenon bulbs.
Comparable LEDs can cost up to 100% more than halogen headlamps (originally introduced in 1962 in Europe, but not adopted in the USA until 1978) and as much as 1.5 times more than HID xenon bulbs (achieving comparable performance to HID xenon headlamps requires a much more expensive LED solution than for lower-performance halogen alternatives).
Generally speaking, LED headlights are stacked in between the halogen and HID xenon lamps regarding their luminescence, but they provide much more focused rays and can also be played with to create different shapes. Also, thanks to their small size, LEDs allow for greater manipulation, with automotive manufacturers being able to create all kinds of shapes and assemblies that would perfectly match their models.
Although LEDs do not emit heat as they light up, they do create a certain amount of heat at the bottom of the emitter when the electricity passes through, thus creating a potential risk for adjacent assemblies and connectivity cables. For this reason, LED headlamps need cooling systems, like heat sinks or fans to keep them from melting.
Furthermore, these cooling systems are located in the engine bay, a not-that-cool area for some other system to maintain a decent temperature. This is another reason why LED headlights are also harder to design and implement in the vehicle, and thus more expensive than HIDs.
Furthermore, Audi recently announced an optional laser high beam in its high-performance R8. This system is excellent at not shining light on vehicles traveling ahead of it that the high-beam can remain on and adjust itself, even with as many as 8 cars in front. Compared to LED high-beams, Audi’s laser spotlight can throw its beam twice as far down the road (over 500 feet), allowing the driver greater distance visibility.
In conclusion, the heady days of the incandescent light bulbs dominance as the go-to choice for lighting needs are waning. It has been a long time coming, but the cost structures normally associated with LED equivalents have dropped dramatically over the past 5 years or so.
So much so, that their price points are now low enough for them to be embraced not only by the consumer, but also by major industries, such as the transportation market segment. Yes, I believe the future is bright for LED bulbs.
Tony Armstrong is director of product marketing for power products at Linear Technology