People striving to improve energy efficiency and cut CO2 emissions often over-simplify lighting.
Oversimplification led congress to needlessly prohibit the manufacture of most types of incandescent bulbs, so as to cut CO2 emissions.
This was an early manifestation of CO2 hysteria, and ignored advancements in lighting technology and the purpose of lighting.
Lighting has three primary purposes:
- Facilitate seeing
The amount of light on a surface, as measured in foot candles or lumens per square foot, determines how easily objects can be seen.
Standards have been established for light levels on surfaces under varying applications.
Machine tool surfaces can require 100-foot candles. Reading also usually requires 100-foot candles on the surface of the item being read. Some precision applications require much higher levels of lighting.
The Illuminating Engineering Society has published tables showing recommended light levels for various tasks in their handbook. These tables may also show required levels of light based on people’s age.
When selecting any type of lighting, it’s important to determine the amount of light that will reach the surface, which depends on the square of the distance from the light source.
This is why fluorescent lighting isn’t suitable for use in factory high bays. The required amount of light doesn’t reach working surfaces. High intensity discharge lamps have usually been used in these applications.
Homes with twenty-foot high ceilings will require more recessed light fixtures than rooms with eight-foot high ceilings, or, alternatively, bulbs that have higher Lumen ratings. When converting incandescent floodlights (R40 or R60 ceiling lights) to fluorescents or LEDs, it’s important to know the Lumen output, and not just the wattage equivalence.
The Lumen output will determine the amount of light, in foot-candles, that reaches the surface.
Safety is the second purpose for lighting.
Differing situations require different levels of lighting. A garage may only require 15 foot candles on surfaces to allow people to walk safely. Sidewalks, walkways and highways may require much higher levels of lighting to allow people to see objects in front of them or in surrounding areas.
Esthetics may initially seem trivial, but in many situations it is vitally important.
Different light sources produce different color readings and renderings.
|Sodium vapor lamps|
The basic measurement for how light is seen is color temperature, in degrees Kelvin. The accompanying table contains a short listing of color temperatures with examples.
Fluorescent lamps and LEDs can have a range of color temperatures. Incandescent lamps, by their nature, fall in a narrower range around 3,000 K.
Color temperatures affect how people see objects.
Department stores are prone to use white light, with temperatures around 5,000 K, for displays. This is close to daylight, which is how people prefer seeing clothing and objects.
Incandescent lighting typically creates a warm ambiance, which many find pleasing.
Artists and photographers are very sensitive to how color temperatures affect their subjects. Even shadows are important, especially in portraits.
Cities around the world appear bathed in a yellow hue from sodium vapor street lights when approached by air.
The architectural committee of Reston, a community of 60,000, insisted on white light for outdoor lighting. They prohibited the use of sodium vapor lamps, which were far less costly to operate than the metal halide lamps the committee desired for street lighting.
It was the committee’s belief that white light rendered objects and surroundings far more pleasantly than did sodium vapor lamps.
However metal halide lamps are estimated to be 200 times more expensive to operate, contain mercury and consume more energy than sodium vapor lamps. It’s also been established that people can discern objects better with sodium vapor than metal halide lamps.
LEDs have come to the rescue, as they last several times longer than metal halide lamps and consume less electricity.
In this instance LEDs provide lower cost and longer life. But, for the average homeowner, LEDs are more expensive and may not result in lower costs.
And this brings us to the point of the article.
It was ludicrous for Congress to outlaw incandescent lighting so as to cut CO2 emissions for ideological reasons, without considering the science and cost of lighting.
At the time Congress enacted the legislation, LEDs were being developed that could emit white light, suitable for reading and for replacing metal halide and other sources of white light. They would also be able to eliminate the use of compact fluorescent lamps that contained mercury.
There was no reason to prohibit the manufacture of incandescent lamps, other than for ideological reasons, when LEDs were becoming available.
Industry and science, under the free market system, had already developed the technology that would replace incandescent lamps in a far less costly and far more orderly manner.
Homeowners were forced to search for incandescent lamps that became increasingly scarce, and to use expensive LED lamps in applications where they were far more costly than inexpensive incandescent bulbs. A 60 watt LED lamp cost more than $20 at the time, while a 60 watt incandescent bulb only cost 60 cents.
While the cost of LED lamps have come down considerably, using an LED lamp in a closet for a few minutes each day, was, and still is, a terrible waste of money for the average homeowner.
Decorator lamps, emitting light at color temperatures similar to incandescent bulbs, cost far more than the incandescent bulbs that are no longer available.
The cost of LEDs continues to come down, which, when combined with their longer life, make LEDs a better buy than comparable incandescent bulbs. The life of LEDs for residential use is determined by when emitted light has been reduced 30%.
There was no need for Congress to prohibit incandescent bulbs. LEDs would have replaced most incandescent bulbs because of the LEDs longer life and lower operating cost.
LEDs use 80% less electricity, on average, than incandescent bulbs, and lighting represents 11% of total U.S. electricity usage, or 15% of residential and commercial electricity usage.
Environmental activists claim up to 75% of the electricity used in the U.S. could be saved by using efficiency measures that cost less than the electricity itself. This is a bogus and misleading claim.
LEDs are the only technology that can significantly improve energy efficiency over the next 15 years without adversely affecting peoples living standards. When other proposals are examined, they either achieve minuscule reductions in electricity usage or require people to lower their standard of living.
If a dramatic and massive switch to LEDs occurs by 2030, when LEDs could have 84% of the market, electricity usage for lighting would be reduced by 40%, or 261 billion kWh, and total US electricity usage would be reduced by 5% in 2030.
This is not the phony 75% reduction activists claim is possible, but it will be a remarkable achievement that can improve, not reduce, our standard of living.
Industry and free markets produced this revolution in lighting, not congress or environmental activists.
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