Anyone listening who has a solution for using LEDs for indoor plant growth (see www.atlanticlivingwalls.ca). I am looking for recommendations on what type and brand of LED's I can use to provide the proper light spectrum for healthy plant growth. The limitations I face is that the lights cannot be up near the plants. They must be effective from a distance of ten (10') feet or more.....
I build interior living walls (vertical gardens) with living plants (mostly house plants that require medium to low light levels). We would like to use LED's. However, the led's I have seen so far need to be within a few inches of the plants. Is there a high lumen, full spectrum led flood light that you can recommend for healthy indoor plant growth?
Thank you Alex and Carol. This was a very informative and interactive show. The Databeans 2011 LED Market Research Report will be available next week, anyone interested feel free to email me any questions about the market. Thanks! firstname.lastname@example.org
LEDs are wide spectrum compared to fluorescents. They lack the reds compared to incandescents. Reds are also inefficient to create, since your eye is not as sensitive to it. There are special LEDs with 90+ CRI. But they are dimmer.
Some companies add in red or amber LEDs to compensate.
People are also looking into using quantum dots instead of phosphors to improve color.
Since no one else is asking more questions, Ill post some more:
Are there are tips when desgning for light guide films with top as well as side firing LEDs? How critical does alignment/solder temperature become? Also how critical is it to keep the light guide surface pristine and prevent any fingerprints/dust/etc?
About AC LEDs. The concept is great. But the two manufacturers that I know of that make them do not have the most efficacious LEDs. Dimming is probably not compatible. The light output would vary when the line voltage varies. You would also need to add protection circuit for surges.
AC LEDs are patent protected. Maybe in the future, once the other improvements are exhausted, they will become more popular.
People complain about "the color", but I like the bluish light. I think it makes things look clearer and more like sunlight than the yellowish ones. So I hope there are lamp choices, not "one fits all".
Variability of color is a limit of the particular equipment. There are spectroradiometers that measure color precisely. Just a question of if you want to pay for it.
To borrow from integrating sphere practices, you could have a few "standard" lights, of blue LED, incandescent, to do a quick calibration across the equipment. Just keep track of the usage of the "standards" so that when they start aging, you replace them and transfer the calibration to the new "standard".
Color binning can be an issue if your specs are extreme. Generally, though, binning is not as bad as it might appear from the datasheet. Each reel of LEDs tend to be closer in color than the size of the bin indicates.
How can one account for the variability in color measurements in between different measurement equipment? It is really hard to calibrate color measurements between different colorimeter manufacturers in general.
Carol's comment about using LEDs in ways that make use of the new possibilities offered by LEDs is right on the mark ... economics seem to be driving manufacturers to develop retrofit products for fluorescent and incandescent, missing out on the best that LEDs can offer
Driver lifetime is a big concern. It can be engineered to your specs, though. Get a good power supply designer. Then can do an analysis on the stress of each component based on current, temperatures, ratings, and come up with a life time estimate or change to more expensive components to increase lifetime.
Databeans projects that LEDs will remain the largest and fastest growing optoelectronics product market in 2011 with $7.9 billion in global sales and a CAGR of 20 percent over the forecasted period. Meanwhile, total unit shipments will reach 95.5 billion in 2011 with a CAGR of 23 percent over the period. Its only a matter of time before they take over the market, environmental will definitely be the leader in this push.
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With strong marketplace demand for qualified engineers across the board that currently outstrips the available supply, there may never be a better time for engineers and project managers to advance their careers and salaries. Whether those moves are successful in the short-term and long-term is likely to depend on how the transition from one job to the next is handled.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.