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Lifecycle Energy Costs of LED, CFL Bulbs Calculated
necro81 writes "The NY Times is reporting on a new study from Osram, a German lighting manufacturer, which has calculated the total lifecycle energy costs of three lightbulb technologies and found that both LEDs and CFLs use approximately 20% of the energy of incandescents over their lifetimes. While it is well known that the newer lighting technologies use a fraction of the energy of incandescents to produce the same amount of light, it has not been proven whether higher manufacturing energy costs kept the new lighting from offering a net gain. The study found that the manufacturing and distribution energy costs of all lightbulb technologies are only about 2% of their total lifetime energy cost — a tiny fraction of the energy used to produce light." The study uses the assumption that LEDs last 2.5 times longer than CFLs, and 25 times longer than incandescents.
Does anyone know if LED lighting can save on power over CFL with the same output (lumens)?
I purchased some LED bulbs and they tend to be much more expensive and the savings (watt rating) is very negligible. What makes LED more attractive? Is it just the longer life time?
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Is heat output. More or less, any energy that isn't becoming light is becoming heat. Now in some areas of the world, that matters little to none. However in hot climates, it does. An incandescent produces more heat which gets dumped in to the air in your house. You then have to run your AC more often. So you end up paying double for the power, in terms of using it and then eliminating the excess. That's one reason I rather like CFLs is that they heat up my place less. I live in the desert so that is a non-trivial thing.
Also, they can have a much more natural white point. I like the fact that you can get CFLs with a white around 6000, which is closer to what you get from the sun on a bright day. Just a much nicer quality of light. You do generally need to pay more to get higher quality ones with a better spectrum, but I'd say it is worth it.
Incandescent bulbs :
+ Cheap, we're used to the light
- terrible efficiency, short lifespan, fragile, sensitive to vibration, emit heat
CFLs :
+ much more efficient, very long lifespan
- not very dimmable, contain mercury, fragile, slow to start up in cold environs, reduced lifespan if toggled on and off
LEDs
+ extremely efficient, ridiculous lifespan (60,000 hours), almost bulletproof, can toggle on and off as much as you want, start up instantly in all environs, dimmable, no toxic materials. Basically almost perfect in every way.
- $$$$$$$$$$$$$$$$. Current generation light spectra is too high a color temperature to mimic incandescents. Current generation packaging creates a narrow, focused cone of light.
Summary : LED will pwn all once the problems are solved, and the problems appear solvable. Problems with other light technologies are inherent to the technology itself and not solvable. Once LED is perfected, the other two technologies will be useless.
i think while this report is bullcrap on how much of a saving you get from led's, in general it's right - there really isn't a reason to keep using incandescent bulbs anymore. I plan on building a new house next year and it'll be all led driven from a dedicated 12v circuit in my house that will run outdoor lighting as well as my bar fridge.
If you mod me down, I will become more powerful than you can imagine....
I suspect CFLs are less tolerant of a bad power supply than incandescent lightbulbs -- depending on how many power spikes you get they may fail sooner. Also, some makes seem to be better than others. For example, it may just have been bad luck, but all the CFLs I have ever bought from IKEA died fairly quickly. On the other hand, I have several others which have lasted several years.
Yeah it seems like CFLs are a great example of YMMV.
I simultaneously replaced all lights in my home with CFLs three years ago. Good quality ones with a nice spectrum similar to old style incandescents (to my eye, at least).
Since then how many have failed? Only one.
I must say I'm quite impressed. Even the outdoor ones haven't died yet (exposed to a typical yearly temperature range of almost 50C). I wouldn't ever go back to incandescents ... and frankly LEDs look even better (less waste heat, potentially better spectrum and range of colours).
To be honest, after having spent more than $400 in LED bulbs (that's not many bulbs trust me), most of them have died after a year or so. I'm talking about the bulbs, not the LEDs of course. I have no doubt they still have 25000 hours in stock, buit without the electronic to light them, it's very little use.
My blog on the subject (in french...)
Write boring code, not shiny code!
The still did not take into account the combination of daylight hours and when central heating systems are on. This is an important consideration for more northerly latitudes. At the moment my incandescent light bulbs are 100% efficient.
We have used a CFL (not the spiral type, but the stright type, philips) for our outdoor light for the last two years. Its still going strong, and we live in unpredictable London (hot-ish in summer, fscking cold in winter)
Have a nice day!
I have looked at it for CFL's (might have been Philipps, but I'm not sure). The deal there was that the shipping and handling cost of a warranty replacement was more than the bulb. With more expensive LED's, that may not be true, but I was pretty ticked off when I found that out (I had one fail in a few weeks that was clearly defective in some way).