Compact Fluorescent light bulbs (CFLs)

[Bluenose]

Regarding the total energy budget of CFLs.

Although glass is used in both incandescent bulbs and in CFLs, in the former it is made by blowing a thin bubble of glass into a mould, a simple relatively low energy process.  CFLs on the other hand are made from tubes of relatively thick glass that is bent into a complex shape and then undergoes the manufacturing process to line it with the fluorescent coating, gas, electrodes and so on.  With respect, I think it is thus disingenuous to dismiss the difference in energy in making the glass component, it take a lot more energy to make the glass part of the CFL compared to the incandescent bulb.

The electronic components in CFLs all require significant manufacturing process themselves, including the extraction of minerals, refinement and fabrication etc, then there is assembly of the electronic unit from the components including soldering etc.  More energy at every step, with no comparable processes in an incandescent bulb. 

The CFLs have a plastic moulding which has to be made, the raw materials of which probably come from oil, require refining and creation of the raw polymer and then )probably) injection moulding.  All these take a lot of energy, again unique to CFLs.

I am not suggesting that CFLs should never be used and there may well be cost saving benefits for some uses, such as our beloved Chatty's front door lamp.  Making a decision to use CFLs on the basis of over all cost is a legitimate exercise and indeed, I use them this way at times myself.  I also use them in fittings that have relatively low wattage rating but I want to get more light.

However, the question of whether CFLs really represent a true energy saving when considering all energy inputs over its entire life is IMO far from certain.

[Bob in a quantum-state-of-faith]

Regarding the total energy budget of CFLs.

Although glass is used in both incandescent bulbs and in CFLs, in the former it is made by blowing a thin bubble of glass into a mould, a simple relatively low energy process.  CFLs on the other hand are made from tubes of relatively thick glass that is bent into a complex shape and then undergoes the manufacturing process to line it with the fluorescent coating, gas, electrodes and so on.  With respect, I think it is thus disingenuous to dismiss the difference in energy in making the glass component, it take a lot more energy to make the glass part of the CFL compared to the incandescent bulb.

The electronic components in CFLs all require significant manufacturing process themselves, including the extraction of minerals, refinement and fabrication etc, then there is assembly of the electronic unit from the components including soldering etc.  More energy at every step, with no comparable processes in an incandescent bulb. 

The CFLs have a plastic moulding which has to be made, the raw materials of which probably come from oil, require refining and creation of the raw polymer and then )probably) injection moulding.  All these take a lot of energy, again unique to CFLs.

I am not suggesting that CFLs should never be used and there may well be cost saving benefits for some uses, such as our beloved Chatty's front door lamp.  Making a decision to use CFLs on the basis of over all cost is a legitimate exercise and indeed, I use them this way at times myself.  I also use them in fittings that have relatively low wattage rating but I want to get more light.

However, the question of whether CFLs really represent a true energy saving when considering all energy inputs over its entire life is IMO far from certain.

Your points are well taken--but.

If one stops production of a CF bulb on a specific assembly-line, then that line will simply switch to something else.

Lowering demand for CF's will not lower the total energy cost of manufacturing--that remains pretty much the same, regardless--something will get made using the processes--may as well be a CF lamp which does save electricity during it's lifetime.

And I do not agree with your assessment that the costs between the envelopes are hugely different. The main cost with glass production is the initial gathering and mixing of the glass formula.  Once it's melted, it can be shaped into simple or complex with pretty much the same heating-budget.  The manipulation-machinery is more energy-intensive, but not that much. 

And consider:  a typical CF will replace between 8 and 10 standard lamps.

I cannot believe that the expense is 8 times that of making a standard bulb--just to break even.

Factor in:  NO ONE recycles standard bulbs AT ALL.  The glass recycling people won't take them, metal contamination issues, plus whatever the white frosting on the inside is made of.  Won't touch'em.

But, the CF's have a high potential for recycling-- the white coating on the inside of THEM is quality chemicals.  The tiny fraction of mercury is worth recovery. The metals in the very small electronic circuit board is usually worth recovery. Even the plastic housing can be recycled.

And--you only need to recycle 1 per every 8-10 of the standard bulbs.  Or--that is an 8-to-1 reduction in waste, if it's not recycled.

If one is going to look at the big picture, one must look at ALL the picture, and not just a single component.

[Aggie]

One reason for buying CF - increased demand will likely lead to further improvements in design and hopefully lowered consumer prices/energy production.  The tungsten-filament bulb is pretty much going to stay the way it is.

[beagle]

There's a theory that the combination of cheaper solar cells and efficient LED lights will sweep across the developing world, particularly in places which don't have conventional power line infrastructure. The important factor there is efficiency at the point of use, not the overall power balance including manufacture and disposal. Some smart financial cookies are backing the idea, as in this article from last Christmas.

[Bob in a quantum-state-of-faith]

There's a theory that the combination of cheaper solar cells and efficient LED lights will sweep across the developing world, particularly in places which don't have conventional power line infrastructure. The important factor there is efficiency at the point of use, not the overall power balance including manufacture and disposal. Some smart financial cookies are backing the idea, as in this article from last Christmas.

What sort of secondary (rechargeable) batteries are they proposing?

I know in many 3rd world areas, primary (disposable) batteries are rapidly becoming a serious hazard-- these folk are used to a "midden heap" for their trash disposal.

When it was mostly organic, no big dealio.  When you dump in toxic metals (battery waste) things change drastically.

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In a related note, cell-phones are rapidly moving into these countries, too.  It's MUCH cheaper to put up line of sight towers than it is to string wires.  All the towers need is a source of power--sometimes they are 100% powered by local generators run off of a variety of sources (the local electric mains are insufficiently reliable)

[beagle]

I don't know if they've come up with anything better than deep cycle lead acid gel batteries yet.

[Sibling Zono (anon1mat0)]

Some crank flashlights have NiMH batteries, I believe those aren't as toxic as other types.

[Griffin NoName]

I don't know if they've come up with anything better than deep cycle lead acid gel batteries yet.

They have come up with all kinds of amazing batteries while building for use in space. One of the briefs: must fit in strange space and don't forget the exact speification of that space will change 7 years down the developemt programme as they discover a different other vital part has to be unexpectedly enlarge. Sounds like the UK Olympic budget.

Must work at extreme temperatures. Lots of other parameters too.

Don't know details (remember) but there sound like lots of potentially useful common battery issues that might well improve earth-bound batteries. But I doubt if anyone is doing joined-up thinking let alone putting up the money. <cynic>

And how about batteries for cars.

Nah!! I definitely see a battery revolution ahead. Will it arrive before Global Warming wipes us out?

[beagle]

I think mobiles/laptops tend to drive the terrestrial battery technology market, but as we've seen with Sony/Dell laptop batteries there are "issues" with very high energy densities. 

[Swatopluk]

Methanol fuel cells are under development. The problem I see is that methanol is a bit unhealthy (though the amount needed to power a laptop may be sublethal).

[beagle]

With solar power in the developing world I was wondering whether you could use electrolysis in the day to create Hydrogen and Oxygen, and then a fuel cell at night to recombine them to generate the power for lights. Is that a very lossy form of power storage (ignoring the possibility of someone inadvertently having a smoke too near the apparatus)?

[ivor]

From what I remember it's fairly easy although a bit dangerous.  You need really pure water to keep impurities from hosing up the process.

[Bob in a quantum-state-of-faith]

From what I remember it's fairly easy although a bit dangerous.  You need really pure water to keep impurities from hosing up the process.

You also may want to use DC current as well, that way, you get the H₂ on one electrode, and the O₂ at the other one.

If you use AC current, you get a mix of gasses at each electrode.  (Useful, if you are a high school nerd trying to fill up a balloon for the purpose of making a dramatic *bang*.  A bit more dramatic than pure hydrogen balloon, in my opinion.  The gas mix that results is EXACTLY the proper volumes to have complete combustion ... )

As for using pure water-- you can't.  Distilled water is not conductive unless you use HUGE voltages-- thousands of volts, I seem to recall.  The USUAL low voltages generated by solar cells is not good enough.  120v mains is not good enough. 220v European mains is not good enough to force current through distilled or pure water.

You need at least a TINY bit of impurities - preferably an ionic sort, like NaCl, to conduct the electrical current.

Again, in HS, we discovered THIS, too.  We'd start with a gallon of distilled water (purchased).  NOT the "de-ionized" stuff, by the way.

Put a pair of electrodes into a glass container. (we'd make these from old carbon-zinc D-cell batteries.  There's a nice thick carbon rod in the middle of these.  Perfect for a water-splitting electrode.)

Have a light bulb in series with the electrodes as "proof" there is a current flowing through the water. Fill container with distilled water.   Light remains dark -- no current (we were using 120v from the mains).  Add a TINY PINCH of salt.  Viola! the bulb comes on, and bubbles form around the electrodes.  Keep adding distilled water, and the salt is never used up -- at least, WE never did see that.

[Griffin NoName]

(ignoring the possibility of someone inadvertently having a smoke too near the apparatus)?

Maybe that's why they are banning smoking in England?

My laptop battery is only useful in the sense that I can remove it when in a black hole. Other than that, I regard it as useless.

My last mobile phone battery came with large warnings about explosions and instructions to disconnect from charger when fully charged. My new one, identical battery, same make phone, says don't worry about leaving it charging all night. From this I deduce two things. One, very few, if any, people got blown up by the first model, and two, they obviously haven't been listening to all the ads about chargers wasting energy when left on all night....

Light is an easier issue than laptop batteries. All those stars out there just giving out light. If we started towing a few in closer now we'd solve the problem for some future generation. 

[Swatopluk]

Or installing some powerful lenses to concentrate the star-light.

The old-fashioned potash lye fuel cells powered with O₂/H₂ have the dilution problem too. The water formed by the reaction dilutes the lye and thereby reduces the conductivity until the cell stops working.