I’m preparing a short persuasive speech (for class in College) with the intend to make people convert to use LED light bulbs instead of incandescent ones etc.
If somebody here knows of any good ACADEMIC sources about this topic, please let me know.
I can’t use websites; only physical high quality magazines like f.e. American Scientist or New Scientist so basically I’m looking for articles from scholarly magazines in English only.
(They can be posted online but the original source needs to be in print.)
I’m using academic databases like Proquest to get together my main information but posted this thread here just in case somebody knows something that I might not find easily searching with conventional methods.
I’m not sure what purpose this is for, but this is an MIT website
I would not currently recommend LED because of high cost, poor construction/failure rate and low output (at present) except in very specific applications such as on/off with short usage (ie bathroom) or outdoor (they don’t seem to attract insects)
LEDs are very reliable. When they fail, it's usually because of the driver. Even the well regarded Cree LED lightbulbs are limited by a component in its driver that's only rated for 1000 hours.
I doubt you'll find many articles in science journals about LED's because it's a commercial product, and as such, you'll find its articles in trade magazines and technical journals. True peer reviewed science journals are going to be mostly limited to development, and sometimes on development of minor parts of an LED. If I wanted to find about how HCCI works, it's benefits, and major developments, I wouldn't look at Science or Nature Magazine, I'd look at the SAE and its european equivalents. For you, I'd start looking at LEDs Magazine, and see if you can use its references to find something that looks better in your citations.
You can also find research and results by city governments that have rolled out LEDs in large public lighting projects. Los Angeles has that.
Books are great, even if you can only find one. You think that won't work because you need multiple references? All you need is one properly referenced book. Whatever the book cites, use that as your citation.
Male Bovine Feces! Yes, initial cost is high, but coming down rapidly. With a little creative shopping, I paid around or less for most of the 300+ LED bulbs in my house than halogens would cost… and that was 2-3 years ago. There were some bulbs I paid a lot for (like $30-$35 each)… the PAR20/95 CRI/550 lumen, the PAR16 500 lumen, and the MR16 490 lumen ones.
Construction quality far exceeds that of CFL’s. Output exceeds what any of my halogens put out. Failure rate has been exceedingly low… like three bulbs have died… all of them driver failures. Before, I was replacing at least one halogen bulb a week. Between electricity and bulbs (and not counting the time saved not replacing hotwire bulbs) I am saving around $100/month with LEDs. Total payback time was around 3 years (could have been a lot less, without some of the experimenting and splurging on those $30+ bulbs). I need to sell of some of the earlier bulbs that I bought and replaced with more advanced ones.
funny that i was thinking of you when i posted that, your in a rather unique situation, if i remember correctly you bought bulbs online from someone selling returns, you had many recall bulbs, and the cree bulb from home depot seems to not be keeping its shell on very effectively (and i believe you mentioned high temps and low lumens)
I would like to say todays LED bulbs are better then incandescent and cfl, but i don’t think they are there yet, but i hope they are soon.
I can’t buy a bulb, give it to a layperson and be confident it will outlast a quality cfl yet, when i can i will change my opinion and start promoting them (notice how i said currently and at present in the post you quoted).
I had high hopes for those cree bulbs at home depot.
I have 10 led bulbs up and running in my house, all lamps that get major use are led now, I expect (perhaps I'm wrong) that I will never change them again in my lifetime. They are all Philips 2700K 80+ CRI, with different forms (on avarage I paid 12 euro for them). My girlfriend never noticed that the bulbs were replaced. Then she came home with a cheap homebrand led bulb from some drugstore, and she knew the first day precisely where it went because of the horrible yellow colour.
My point is that the led bulb is already there, but there is so much rubbish on the market that the good bulbs do not get the use they deserve.
It all depends upon the bulbs that you buy. Three are good bulbs out there and awful bulbs.
Even at retail prices, the payback over incandescents is there now. When I started, a 15 watt/900 lumen PAR38 LED bulb retailed for around $70, and I paid around $10 or so for mine. 8 watt/400 lumen PAR20’s retailed for around $45. An equivalent incandescent bulb was around $5 in the same form factor. Today, good quality LED bulbs can be had, retail, for around $20. Note that all of the bulbs in my house are recessed spot bulbs… no plain ’old globe bulbs here… those seem to be a bit behind the development curve.
The recalled bulbs were a bit of a fluke… all made by the same manufacturer for different people. Their driver had a potential problem. There have been FAR more problems with CFL bulbs burning up than LEDs. I personally know two people that had house fires (one devastating) due to bad fluorescent lights.
People are way too shortsighted to see the payback potential for LED bulbs even at todays prices… a little math shows the decision should be a no-brainer. You can pay now, up front, or bleed bucks over the long term. I don’t see LED bulb prices falling nearly as fast as they have recently. Even with a zero emitter cost, driver/optic/heatsink materials cost is not going down anytime soon.
I would buy LED bulbs for me, i am not bothered by hiccups, and i have no qualms about payback period (though you are comparing to incandescent not fluorescent). I buy only quality cfls because for years i had longevity problems so i pay extra for quality and longer then 5 year warranties. I would not buy led bulbs (with an exception for the phillips if i can find it) to give to others saying they are maintenance free and going to last decades because there are far too many examples of that not being the case. A non LED person would not care its the driver that failed instead of the led or the glass covering fell off because it not joined correctly or with glue that can’t take the high temperature or cannot be installed base up, but for BLFers a few hiccups are practically par for the course. Most people turn on the switch and want maintenance free light that lasts as long as advertised.
I also want 1500 lumen output per bulb, because i use 23W cfls (100 watt equivalent) and led bulbs are not matching that yet.
Your situation is a bit different, you have many halogens, more bulbs then most people and you needed to replace them so often i’ve replaced no cfl bulbs for failure in the last 3 years, though mine that are running twice over their rated lifetime are probably on their last legs
Again i hope all this changes and soon, i would like to be able to give led bulbs to customers and acquaintances without a strain on my reputation because its reliability is not what they are expecting.