LED INFO

I scoped out a site with person named Pablo Päster who wrote an article about LED lights. The article itself is really informative and compares incandescent, CFLs and of course LEDs against each other based on efficiency and cost.

Here is the meat of it, once again this is written by Pablo Paster!

...A 7W LED can be compared to a 10W CFL, which also emits 500 lumens. The closest incandescent bulb that I could find was a 460-lumen or 40W bulb. The next thing is to compare the efficacy of the bulbs. This is done using the measure of lumens per watt, or light emitted per electricity input. The incandescent bulb has an efficacy of 12 lumens/watt while the CFL has an efficacy of 50 lumens/watt, only to be outdone by the LED at 71 lumens/watt. So it's clear that LEDs are by far more efficient than incandescent bulbs. But does this justify forgoing CFLs in favor of LEDs? At over $50 per bulb, the high upfront cost will give everyone pause. But is the long lifetime or the high efficiency worth the cost?

A 10W CFL, available online for $6.90, has an expected median lifetime of 10,000 hours. While this is about 10 times longer than the life expectancy of an incandescent bulb, it is only one-fifth the expected life of the LED. So LEDs have the potential of cutting down on ladder time by a factor of 50 over incandescent bulbs! At about 25 cents apiece, the incandescent has by far the lowest upfront cost, which is why many people still use them. If we normalize the cost of all the bulbs over a 50,000-hour period, the incandescent bulbs cost $12.50, while CFL bulbs cost $34.50, and the LED bulb costs $59.95. But, as you may already know, the upfront cost of a bulb is by far the cheapest part. It's the electricity required to operate the bulb that adds up.

Over a period of 50,000 hours, a 40W incandescent bulb will use 2,000 kilowatt-hours (kWh). At 15 cents per kWh, this will put $300 in the pocket of your local utility, bringing the total cost of the incandescent bulb, over 50,000 hours, up to $312.50. The CFL bulb only uses 500kWh over the same time period, or $75, totaling $109.50. Finally, the LED bulb will use 350kWh for $52.50, with a total cost of $112.45. So, in this example, the LED light does cost a few dollars more but the difference is negligible. Think of the time you will save by not running to the store to buy bulbs and climbing the ladder to change them.

As for their disposal, LED lights, unlike CFLs, contain no mercury and many of them are compliant with the European Union's Reduction of Hazardous Substances (RoHS) directive. Like CFLs they do contain electronic circuits, which are hard to separate back into individual materials for recycling. But with a life span of 50,000 hours, the relative amount of waste created will be quite minimal...."

http://www.salon.com/mwt/feature/2008/05/05/ask_pablo_leds/index.html

-CHRIS_C-