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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."
Did you notice all the LED xmas lights this year?
Although I agree with some points of your post, most of your belief is not quite accurate. LEDs now make the best flash light illumination, and the power drain on batteries is minimal. I've been using LED headlamps for years, so this is nothing new, as your post implies.
The problem with them being used in homes is that they direct their illumination to a specific spot. This is not a bad thing though. I've recently seen them configured as spot lamps. Perfect for recessed lighting.
The optics in LED technology can easily be modified to diffuse light to make a great replacement for CFL & incandescent. Give it time.
"Suppose you were an idiot...and suppose you were a member of Congress...but I repeat myself." Mark Twain
If a 25W CFL replaces a 100W incandescent bulb, and the CFL lasts 8000 hours, it will save 600 KWHrs of energy. .11 gallons of diesel for the journey. That is about 6 KWHrs of energy.
If a shipping vessel can hold 35,000 tons of cargo and the shipping weight of a CFL is 1/2 pound, the vessel can hold 140 million bulbs. Of course there is not enough space for them all, but they can ship with heavier items, and I am assuming costs are allocated by weight.
If a 7,000 mile journey burns 875 tons of fuel, or 15.75 million gallons, then each bulb is allocated
Therefore, the shipping costs don't even come close to negating the energy savings.
You are either buying CFLs from a completely incompetent manufacturer, or simply have a bizarre situation where reality is bending around you.
I replaced all bulbs in my home with CFLs three years ago. None have burned out to date, and I saw a small but measureable decrease in home energy use, as my home energy costs are very stable. Everyone I know who has replaced all or some of their bulbs have had the same experience.
There's demonstrable energy savings to be had, and a measureable lifespan increase simply due to the physics of CFL versus incandescent.
A 20' container is approx 19' x 7' x 7' or 1.6M cubic inches (it's a bit bigger, but I left room for pallets, etc).
If a CFL + packaging is 3" x 4" x 6" = 72 in^3 then you can fit around 22,000 of them into a 20' container
This site claims you can ship a 20' container from China to the US for $3800 USD
Let's say that 75% of the shipping cost goes toward fuel, the rest goes to labor, paying off the ship, container rental, etc. Sounds reasonable.
I'm going to use Diesel for the energy calculations. I know that ships run off bunker fuel, not diesel, but I have to think that the cost per unit of energy for bunker fuel is cheaper than diesel since it's less refined, so by using Diesel I'm being conservative. Right now you can buy diesel for under $2/gal, so with 75% of $3800, we can buy 1425 gallons of diesel.
Diesel has 38 MJ of energy per liter (143 MJ/gal), or 40KWh according to the units command.
So, each light bulb uses 40KWh / 22,000 = 1.8 KWh (1800 Wh)of energy
A 29 Watt CFL can replace a 100 Watt incandescent bulb, so that's a 71 watt savings... 1800Wh / 71 W = 25 hours
Sooooo....a CFL will save the energy used to ship it in about 25 hours of operation. CFL's are supposed to last 5000 hours, so over its lifetime, it will save over 200 times more energy than used to ship it. (of course, this is only this shipping energy, and ignores the extra energy that it took to manufacture the CFL it as compared to an incadescent. I don't know how to do that math).
No, it's valid if they're both made extra-nationally, but in different places. Most incandescents are actually made in the United States by GE, but the vast bulk of the remainder are made in Mexico, and shipped up by rail, which is far more efficient than slow-boating them from China. It turns out that there are more than one country outside of America, and that those countries aren't actually all in the same location.
Of course, if anyone actually did the math, they'd find out that the energy cost of shipping is offset by the energy savings in usage in under three days; sometimes I wonder whether people have any idea how many lightbulbs fit on a large boat, or how little fuel a large boat actually needs.
But hey, made up math is great for making arguments, right?
StoneCypher is Full of BS