"One Perfect Part at a Time"

Lighting Efficiency

I am a professional Certified Energy Manager (CEM) with a few other credentials (BEP) (CSDP). So let me say my real occupation is in energy management and conservation. I am not one of the radical “save the planet” phreaks, but I do take a very practical sustainable approach to energy management.

So anything that can be done with reasonable expectations and return on investment is on my todo list. Many things being promoted today are more political fodder than a practical solution.

One great advance today is in LED lighting. Where there is a need for good lighting, very low heat and a huge reduction in power, the LED lamp has come into it own. Here is what I have begun in my own shop.


LED LightingThis is my X3 small mill. I have two task lights, one mounted on each side. Each fixture is rated for 100 watts but I always used 50 watt PAR20 bulbs. You can see one illuminated in this picture. Using both fixtures, it is 100 watts and most of that power is radiated as heat rather than light.

You can see how “warm” the color tone of the light is. This is typical of incandescent bulbs, especially as they age.





LED LightingHere is a closeup of the same picture as above. On the left is the incandescent 50 watt bulb next to the 9.5 watt LED PAR20 bulb. On the right is how the LED bulb is packaged. You can see on the package it is a PAR20 FLOOD, lasts 30,000 hours and is 500 lumens. I chose the 5000°K bulb which is a very white “outdoor” natural daylight color. So it uses more than 5 times less power and will last 15 times longer than the old bulbs. The LED lamp is built far more rugged than the frail thin glass incandescents. Much safer in this environment.





LED lightingThis is the LED lamp illuminated inside the fixture. You can see there is only a slight band of light around the edge of both the white and the black reflectors. The bulb directs most of the light out in a 38 degree cone angle. Almost none is wasted inside the fixture. With two bulbs I have 1000 lumens of light on my work. (Bright!) LEDs do produce a little heat in the bulb but they do not radiate heat onto the working area. They are very cool to work under.





Led ightingHere is a fixture with the LED PAR20 and the power off. The bulb is fairly heavy and made of ceramic. It is designed to conduct the heat directly from the diode junction and into the ventilated shell. This is part of the reason for the long life. What we have here is a 9.5 watt bulb in a 100 watt fixture. Good safety factor. I never have figured out what the spring clip on the shade is for. With 100 watt bulbs the shade may get hot and the clip is a cool place to grab to adjust the light direction.






LED LightingThis final picture shows the lighting in use. The change to a bright white light color (degrees Kelvin) and the 1000 Lumens do a wonderful job of illuminating the workspace. I expect the initial cost of the bulbs to be offset by the very long life, but the real benefit is the greatly improved visibility on the mill table. Not all energy management is strictly payback or ROI.




Update 11/29/14:

I just upgraded two more shop task lights to the LED bulbs as above. This time they were Sylvania brand, made in Mexico. All stats are the same except 9 Watts for same lumens. I also upgraded a three fixture track light with PAR30, 3000ºK LEDs inside the house. We went from 65 watts to 12 watts per bulb. I have changed them 4-5 times in the last 17 years. It’s hard because they are 18 feet high above the fireplace and requires an extension ladder (inside the house) to change them. With LEDs it may be my last time. The LEDs are dimmable like incandescents so the existing dimmer switches work fine. There is also much more light (on high) with the LEDs. Dimmers recommended for proper “mood” setting. Note: The color (Kelvin) of an LED seems to be constant even when dimmed. These lights are almost never on full high.


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