New Flat & Flexable Plasma Lamp To Topple LED, But Not Just Yet - Page 1
Forum section: electronics / general

author: SgtRock
author_rank: Unknown
timestamp: November 22, 2011, 04:25:03 am
content: Greetings EEVBees:--See the below link for an article from TheRegister about a new plasma lamp.http://www.theregister.co.uk/2011/11/21/scientists_make_new_lightbulb/--The article is by Brid-Aine Parnell, who writes technology, business and science articles for TheRegister and other publications. She notes that the arrays are flat, flexible, can be dimmed, and have no mercury; but read the article. Ms. Parnell also mentions that fluorescent tubes are about 80 percent efficient, but that much of the light is wasted do to the 360 degree emission pattern, a drawback the the "Plasma Lamp" does not share. This led me to wondering about the spiral fluorescent bulbs. I was curious to know how much of their light is reabsorbed on the inside of the spiral coil, and if this fact is taken into consideration, when their efficiency is compared to that of a common incandescent bulb. It seems to me that the "Kentucky windage" estimate for re-absorption in a "curly bulb" would be about 25 percent.--Sometimes indirect lighting (bouncing it off of the ceiling) is a desirable characteristic, and sometimes it is not. Nuff said. Straight fluorescent tubes, spheroidal incandescents and LEDs, depending, of course, on how they are housed and reflected can emit all or nearly all of their light, without re-absorption, but the humble "curly que" cannot.--If anyone knows how the efficiencies for various types of lighting are arrived at, and whether a re-absorption factor is included; your comments are humbly solicited.--My thinking is that the "curly bulbs" may not actually be as efficient as claimed, but of course, I am not sure.--LEDs and other, soon to be, "highly efficient" light sources sometimes have a hidden advantage; I.E., if your abode is in a warm climate where the air-conditioning is on a good deal of the time. Heat created by lighting must be carried away by the AC. You have to pay to introduce the heat into your living space and then you have to pay, say 130 percent of that amount to get rid of it. When you are using the heat, the heat from lighting is a boon, so no worries there. Someone living in, say for instance, Sydney and using Wind Power might find it cost effective to use LEDs because of their absolute and working efficiency, plus the fact that the lower total instantaneous demand would provide more headroom. Are these good enough reasons to use LEDs or other highly efficient light sources? If only we knew someone who meets these criteria, he could tell us."If you build a better mousetrap, you will catch better mice."George Gobel 1919 1991Best RegardsClear Ether

author: PetrosA
author_rank: Frequent Contributor
timestamp: November 22, 2011, 04:54:55 am
content: Just as an aside, I don't recall seeing any changes to the NEC as far as calculating lighting loads based on energy efficient lighting for residential (not that I do lighting load calcs a lot...). That might mean that it's not really a prime time deal yet or that the NEC code panels are still playing catch-up or that they're still playing it safe since so many of the energy efficient lights are made to be retrofitted into high wattage lamp fixtures.I will say that LED vs. halogen lighting can have a huge impact on AC calculations. I wired a gallery/store a few years ago where the owner didn't tell the HVAC guys what the lighting would be. A few hundred halogen bulbs later, the AC system couldn't get the store below 85-90 degrees in the summer time with all the lights on. Sheesh.