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Why LEDs Don't Beat CFLs Even Though They Should
TaeKwonDood writes "LEDs don't beat CFLs in the home yet, but it's not simply because PG&E is getting rich making people feel like they are helping the environment buying CFLs made in China that are shipped to the US using a lot more fossil fuels than they save. It's a problem of indication versus illumination. However, some new discoveries are going to change all that."
You're seriously trying to claim that the savings of CFLs are offset by shipment? Really?
I would go into the obvious math or the economics, but honestly this is just simply too stupid to even deserve further comment, except that it is a completely asinine, baseless statement that I'm sure will be picked up and repeated by a lot of ignorant contrarians.
Sorry but I don't buy the optics issue. It really can't be THAT hard to put a lens or reflector in the armature and point multiple LEDs in different directions. If anything LEDs should be preferable to incandescents because it is easier to take something very directional and spread the light than it is focus the light from a divergent source. I think the main reason LEDs are not popular yet is cost and "it's not what I'm used to". Seeing the type of crap people will buy even when there are better alternatives I simply don't believe that something as sophisticated as the beam profile of an LED will be a huge issue.
But what if you had to ship 6 lights for every one due to lifespan differences?
Wow. Way to sneak in that lie under the radar. Politically motivated, or just simple ignorance?
In any case, no, the manufacturing and transport of CFL bulbs absolutely does not generate more CO2 than that saved by using them (assuming coal/natural gas powered, the only logical comparison in this case). Let's run some simple numbers.
Assuming an average 60-watt equivalent (12 watt nominal) CFL bulb with a lifespan of 10,000 hours, it will draw 120kWh over the course of its life. The 60-watt incandescent, if it lasted as long, would draw 600kWh. Of course, it doesn't last as long, but rather an average of 1/5 as long.
So the savings are roughly 480kWh for an 800lm fixture. That's the equivalent of over 400 liters of gasoline burned in an internal combustion engine, and that doesn't include the fuel used building, shipping and shopping for replacement incandencents, which as mentioned burn out far more frequently.
Now for some logic. How is it that a bulb which apparently requires >480kWh of energy to build/ship ($48 at $0.10/kWh) sells for a few dollars? Hint: it doesn't require >480kWh of energy to build/ship, or anywhere near that.
CFLs offer a massive net efficiency gain, and by extension, a net reduction in CO2 emissions. Even factoring in disposal costs at 5 times the manufacturing cost (silly), CFLs are a net win. So please don't spread that tripe!
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Have you done it recently? The CFLs I bought in the nineties are still working. The ones I bought last year aren't measurably any longer lasting than the few incandescents I still use. I suspect that now everyone has jumped on the bandwagon, there are a lot of crappy cut-rate CFLs being made. And I'm pretty sure that this isn't being taken into account in figuring overall real-world environmental impact.
Contributing to this, as Fred and Ethyl Mertz buy eight-packs of CFLs at Costco, they're certainly using them in situations where they don't work well -- like areas where the lights go on and off frequently. (I made this mistake initially -- couldn't figure out why CFLs were lasting months rather than years in the bathroom.) Which, as you point out, really is doing it wrong. CFLs work well in narrowly-defined environments -- they're not a replacement for every bulb in the house. The general public doesn't appear to realize this, and the retailers are in no hurry to correct their misunderstanding.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
A glass of cloudy water would do what you ask, quite easily.
Space Shuttle was a program that strapped humans to an explosion and tried to stab through the sky with fire and math
Without even doing any calculations of the amount of fuel needed to ship the CFL, it's obvious that this environmental cost is more than offset by the savings in power of using a CFL vs an incandescent. The simple way to figure this out is to look at the price, and the cost savings of the bulb over a couple months time. A new CFL only costs a couple dollars to buy. That means (unless companies are selling them at a loss) that it costs less than this amount to ship the bulb to you. Assuming for a minute that the cost of energy in fuel and coal powering a power plant are the same (with the same efficiencies etc, in reality the power grid powered by coal is generally cheaper per watt, but that's okay), if you can make up the cost of the bulb in a matter of months by lowering your electric bill, you have more than made up for the cost of shipping.
I always laugh when people start talking about carbon footprints and all that. Currently the simplest and only real way to drastically reduce your carbon footprint is to spend less money. Things that cost more in general have a greater carbon footprint (there are exceptions to this rule, but it often holds true). So the footprint of manufacturing a new stove is roughly proportional to how much the stove costs (obviously if you're buying a gold plated stove with platinum racks this won't quite hold true). So the quickest way to halve the US's carbon footprint is to cut the US's spending power in half. Of course, with the steps the government is taking to reverse the current economic crisis, they could easily accomplish this.
Phil
That article repeats a bunch of CFL myths. I find it amazing to watch some in the geek crowd glob onto any "science" related conspiracy ("global warming is fake", "the Hindenburg didn't burn from hydrogen", etc) the same way tin-foil hat people glob onto the "moon hoax" or "there was no plane crash at the Pentagon on 9/11".
We even were treated to one in the header of this article:
"CFLs made in China that are shipped to the US using a lot more fossil fuels than they save."
Oh, really, is that so? Shipping cargo takes about one gallon of gas per ton of cargo per 500 miles. Shanghai is ~6500 miles from LA. Thus, 154 pounds can cross the Pacific per gallon of diesel. A gallon of diesel contains 130MJ. A CFL weighs perhaps a quarter pound. Therefore, it takes 211kJ of fuel energy per bulb. If we assume the big diesel engine is roughly as efficient as a power plant's electricity generation, we can compare them directly. 211 kilojoules is 0.05 kilowatt hours. If usage that bulb reduces 60 watts down to 15, thus saving 45 watts, it'd take barely over an hour to pay off the energy used in shipping it.
Of course, you also need to include train shipping energy consumption to get it to and from the ports, which is more like one gallon per ton per 300 miles, but that too is trivial to pay off.
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