Solid State Lighting Reality 101

Posted: November 19, 2008 in General SSL Commentary
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In the late 19th century, a new and seemingly magical science emerged in the form of distributed electrical energy. At the same moment, the automobile and airplabe were also entering the market. As the Civil War played itself out, the world changed in profound ways, for every person on the planet. The transformation changed our lighting from fuels sources to electric light. Horses stayed in the pasture as owners rode in new cars. The population of cities exploded, and farms blew away in dust storms. In this same period of time we suffered the Great Depression. Heading into World War One, everything had changed, everywhere.

We are on the verge of a new transformational period of similar proportions today. We MUST get control of our energy consumption. The population has doubled since 1970. We are consuming natural resources and fuel on an unprecedented level, with growth of developed nations threatening to double what we consume today.

Like the fires caused by gas lighting threatened cities, the filth of horses in the cities, the depression, and exploding population of the late 19th century, we are facing a period of necessary change. Lighting is in the very epicenter of this issue.

Energy conservation in lighting has evolved well in the last 30 years. Now its time to step up and press this even further. With incandescent technology, the best hope we have is an efficacy of 45 lumens per watt. Fluorescent will produce no more than 110 lumens per watt. HID white light sources are locked at about 90 lumens per watt. LEDs are capable of generating efficacies of 140 lumens per watt, likely 160 at their peak. This represents an improvement in the core technoloigy of no less than 40%. Add to this the directional efficiciency of LEDs in directed light application, realizing luminaire efficacies of up to 155 lumens per watt, compared to the best fluorescent systems at 100 lumens per watt in real-world application, LEDs can potentially produce savings of 55% over fluorescent sources, and 85 to 90% over incandescent.

These numbers are real, and will be reached in the next 5 years. As costs drop for LED devices, and manufacturers learn to employ the technology, their is a very real potential for a large scale transformation of lighting from glass tube resisters (incandescent), glass arc tube (fluorescent), and pressure arc lamp (HID) to solid-state devices within a period of 10 years. There is no doubt involved here. This is not a matter of a few rouge marketing nuts making unsubstantiated claims. This is the reality of millions of dollars of research and continuous improvement. Lab tests are proving the concepts, and the time from test bench to market are getting shorter each year.

The fact that energy production is costly, and dirty, will place a great deal of pressure on the lighting market to make the transofrmation reality as soon as it is possible – if not sooner. The additional cost of a luminaire employing LEDs is nothing compared to the total costs and impact of building a nuclear plant, or coal fire facility.

While at this very instant in time, solid-state lighting is just beginning to be viable for large scale general illumination use. In just 9 years, LEDs have evolved from 15 lumens per watt color effects lighting to efficiencies that challenge all incumbent technologies. In another nine years, this market will not only exceed its past performance, it will be adopted by an exponentially expanding number of manufacturers. Behind the transformation of lighting will be an equally, of not more dramatic transformation in how we generate energy. Wind and solar power are also gaining ground, just as gas and alternative fuels sources will reduce our dependance on fossil fuels. 20 years from now the energy and lighting markets will be as different as a rotary dial phone is from an iPhone.

Being cautious and moderately cynical of new technologies if you must. This is healthy, and will keep things real. However, don’t for a moment believe that LEDs and/or solid-state illumination is a fad, that it will eventually fade and be applied only in color or specialty applications. While many are fretting and wringing hands, and hanging on to the beleif that conventional lighting has a real future, there are others expending a large amount of time, energy, and money betting the hand wringers and cynics are wrong. These enthusiasts are well backed, include more PHDs and MBAs than lighting has ever seen, and are employing laboratories full of scientists who have never know the world without cell phones and iPods.

Solid-State lighting is here, it is upon us, and it is an exciting new horizon in lighting design and application. The next big step will be in loosening the grip we all have on past practice and familiarity with old technologies we grew up with. This is not easy, it is just reality.

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