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Questions Arising On Mercury In Compact Fluorescents
Patchw0rk F0g sends in an article from MSNBC on how some environmentalists are having second thoughts on compact fluorescent bulbs. Their relative energy efficiency is unquestioned. The problem is the mercury — enough in one bulb to contaminate 1,000 gallons of water, even in newer low-mercury bulbs. The EPA has an 11-step cleanup process to follow when you break a CFL in your home. The specialized recycling facilities that are needed are thin on the ground — about one per county in California, one of seven states where it is illegal to dispose of CFLs in the general waste stream.
The article barely mentioned the real facts. The power production for regular light bulbs over the lifespan of a CFL generates 2-3x as much mercury as is in the CFL. They are just fine.
Now it is a bit of a problem right now finding a place that will recycle them. Ikea is doing it, and Walmart is thinking of rolling out recycling bins in their stores. But industry needs a lot more motivation to start taking these back. Ideally most municipal recycling programs would allow the bulbs to be placed in their bins (maybe in cardboard protectors or something. A decent article would have focused on this aspect of the story, and it was again just mentioned in passing.
No, the mercury in a "bulb" is in liquid form..... well, liquid and vapor.
:D
The powder in a CF "bulb" is the phosphor, which is toxic and hazardous in an entirely different way.
And, because basically the same stuff is in fluorescent bulbs and white LEDs, nobody wants to make a big deal out of it.
Oh, and injecting mercury is not that bad. Metallic mercury is not especially dangerous, especially because your body is already equipped to excrete a reasonable amount of it. Organic mercury compounds, on the other hand, are hideously unsafe and some of them are toxic in quantities as small as a spilled drop, largely because they have an easy time crossing cell walls.
Gentoo Sucks
1. Mercury oxide is as toxic as metallic mercury. The worst are mercury alkyls since they are the most readily absorbed
2. Mercury in filling is amalgamated with other metals and practically stable against leaching or vaporisation. Some studies have suggested you absorb more mercury by having old fillings drilled out than by leaving them in for a lifetime.
To put the whole problem with the CFB mercury in relation, 100 Million light bulbs at 5 mg each contain a total of 500 kg of mercury.
The EPA estimate for mercury emissions from coal fired power plants is 50,000 kg a year.
I'm aging rapidly, I bought a new game and had no idea if my machine was good for it.
, they will STILL reduce the overall mercury emission into the environment over their lifetime, compared to equivalent incandescent bulbs.
Mercury (and uranium!) is present in the smokestack emissions from coal-burning powerplants. By reducing the amount of electricity used, CFLs actually reduce overall mercury emissions. And since the mercury they do contain is in a sealed glass tube (as opposed to being spewed into the atmosphere and settling out onto the ground), their toxic content is easily managed through recycling efforts.
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No. Elemental mercury at room temperatures is a liquid with extremely low vapor pressure, and will eventually (and slowly) evaporates. Long-term exposure (years) to high concentrations (break a CFL bulb and grind it onto the floor, every week, for a decade, in an unventilated room) mercury vapor is a bad thing. Oxides of mercury aren't really the point -- but for what it's worth, they're even less reactive than elemental mercury, and elemental mercury at room temperature isn't terribly bioreactive. You could swallow some (although I don't recommend it!), and you'd likely suffer no ill effects beyond some spectacularly shiny turds.
The scary MSDS sheet that someone else posted below speaks of mercury in its vapor form. Most metals, when heated to the boiling point, will present immediate dangers to life and health, and mercury is no exception. Because mercury boils at 365C (675F), liquid mercury is a Very Bad Thing to expose to fire.
The kind of mercury you really have to worry about is when it hooks up with organic compounds; dimethyl mercury is a potent neurotoxin.
The reason we worry about CFLs being introduced into the waste stream is that the minute concentrations of elemental mercury can work their way into (and up) the food chain, and because interesting chemistry can happen when water leaches through waste dumps, and/or through fish.
The reason CFLs are still a Good Idea is because the burning of coal also results in mercury emissions. If a CFL consumes 8 watts for 10000 hours, and is then disposed of into the waste stream, its mercury must be added to that released by 80kWh of coal-burning. (Actually, more like 40kWh of coal-burning, assuming 50% of your power can come from nuclear, geothermal, hydroelectric, natural gas, solar, or wind.) In contrast, ten mercury-free incandescents (consuming 100W for 1000 hours each, times ten bulbs for the same 10000 hours of light) produce zero mercury waste by themselves -- but they also produce the waste associated with 1000kWh (at 50%, 500kWh) of coal-burning. Since (500-80=) 420 kWh of coal-burning introduces more than 5mg of mercury into the atmosphere, you're still doing the environment a favor by using a CFL, even if you just throw it into the garbage 10000 hours later when it finally expires.
2. Isn't there more mercury in a filling. In other words, we're breathing mercury vapors all the time - if we have fillings?
Yes and no. Yes, there is mercury in fillings. No, this mercury doesn't vaporize because it's a solid, locked up in the form of the other metals with which it's amalgamated. Elemental mercury is a liquid at room temperatures, and yet your fillings aren't liquid. The amalgam in dental fillings is an alloy of mercury and other metals -- and much as bronze is an alloy of tin and copper, or solder is an alloy of lead and tin (or silver, bismuth, and copper for lead-free solder), the physical characteristics of alloys are, while well-known and researched, not intuitively derivable from the physical characteristics of their component metals.
> 3. Isn't it interesting that In the meantime, manufacturers of incandescent bulbs are not going down without a fight. and then GE is mentioned?
GE's lighting products make money for GE whether you use incandescents or fluorescents, or LEDs. If they can make an incandescent with the same energy usage and up-front cost of a CFL or LED, that'll be a winning product. GE's financial interest in MSNBC probably has something to do with it, but the sentence would be just as applicable to other manufacturers of lighting products.
Ladies and gentlemen, a bit of math.
Amount of mercury in 1 CFL light bulb: 5 milligrams (source: TFA)
Amount of energy saved by using a CFL bulb instead of incandescent, over the lifetime of the CFL:
10,000 hours * 75 watts * 75% energy savings = 0.6 megawatt-hours
(http://en.wikipedia.org/wiki/Compact_fluorescent_lamp#Lifespan)
Fraction of that energy that would be generated by coal-fired power plants: about 50%.
(http://www.eia.doe.gov/cneaf/electricity/epa/epat1p1.html)
Coal power plant energy savings: 0.3 megawatt-hours
Annual emission of mercury by US coal-fired power plants: 48 tons/year in 1999
(http://www.nescaum.org/documents/rpt031104mercury.pdf)
Power output of US coal-fired power plants: 1,900,000 gigawatt-hours in 1999 (about the same today)
Mercury emitted by coal plants: 48 tons / 19000000 GWh = 23 milligrams per megawatt-hour
Power-plant mercury emissions avoided by using a CFL bulb over its lifetime:
7 milligrams
So it's a wash. The amount of mercury in the bulb is roughly the same as what would be emitted by a coal-burning power plant, if you stuck with incandescent bulbs.
But the mercury in a CFL bulb is a lot easier to clean up than the stuff spewed into the atmosphere by power plants.
First, I will overlook the nonsense about GW.
:) ).
Second, why to use CFL? BECAUSE of mercury. The vast majority of power plants in the world ARE coal plants. If you burn the CFL for an average 1 year period AND you break the bulb outside of your house, you will still have introduced less mercury into the atmosphere than had you used the best incandescent over that time. Why? Because even Western American coal has a lot of mercury, and that is considered some of the cleanest coal in the world. Burn Eastern American or worst of all, most seams in Chinese coal and the mercury content is ENORMOUS. So, if you want to lower the total mercury in the air and environment, then use the CFL. If you are concerned about a mercury bulb breaking in your home, do not use them in places prone to breakage. For example, do not put it in a lamp that can be tipped. Likewise, do not use them around the mirrors in the bathroom or the garages. AND most of ALL, do not put them in the kids rooms. If there is a breakage, you must ventilate the house for a while AFTER the clean-up.
If you are still concerned about the mercury in your home AND want to lower your OVERALL energy bill, then get some LED lights. They will pay for themselves over a 1-2 year period, though hard to believe with a $1/watt bulb. Of course, like CFL, the light takes getting use to. I wanted to replace some halogen hockey pucks (10 watts each) in our kitchen with led pucks (2.5 watt), and the wife said not a chance after seeing it in action. Funny thing is that the leds was actually brighter. But, happy wife, happy life (of course, that statement ignores sociopathic ex's
If you're talking about the unnatural color balance, then LEDs are no better than fluorescents. If you're talking about the flicker, then you are probably basing your experience on old fluorescent tube fittings that use a magnetic ballast at mains frequency (50-60Hz). Modern compact fluorescent bulbs use a high frequency electronic ballast that eliminates flicker completely.
This particular topic has been discussed at least once as an article on slashdot, and almost every energy related topic ultimately wanders onto mercury in fluorescent light bulbs.
However, here's the abbreviated facts (and I apologize I'm not going to go look up all the numbers again, but if you don't take my word for it, you can look the numbers up yourself):
A typical compact fluorescent light bulb has about 5 mg of mercury in it. All NEMA manufacturers voluntarily agreed to this a maximum. This is roughly as much as is contained in 50 cans of tuna. The FDA recommends consumers limit their intake of tuna to 1 serving per week, so that's about the same as a year's supply of tuna. So is this enough to be a health hazard? Not really.
First of all, the tuna contains the compound methylmercury, which is formed by bacterial action and bioaccumulates much more readily than elemental mercury. A greater portion of the latter passes through the body unretained. Secondly, you eat the tuna. Nobody eats a light bulb. Not to mention, the FDA recommendation is conservative, except in the case of children and pregnant women.
Generally, the lightbulbs don't get broken until disposal, and therefore completely contain the mercury, but if it does, it can safely be disposed of in the garbage. The EPA recommends that you not touch the pieces with your bare hands, so use a broom and put it in a bag. Most of that tiny amount of mercury is actually condensed on the phosphor that lines the bulb, and therefore fairly effectively immobilized, although it will slowly evaporate.
Is it an environmental hazard? Again, not really.
The EPA has calculated, based on the US's current power source mix, that the mercury contained in a CFL is more than offset by the power savings, which reduce the amount of mercury released into the atmosphere by burning coal. Additionally, don't forget that the mercury is trapped inside the bulb until broken. Even then it's at best a small concern. Most of the mercury in the environment is naturally occuring, although in specific areas industrial pollution has resulted in significantly elevated mercury levels.
Additionally, due precisely to disposal concerns, many CFL retailers have implemented recycling programs so you can drop off you dead CFL's and they will dispose of them properly. Not only that, but non-commercial users are actually allowed to dispose of fluorescent bulbs in the trash in most cities. Sound bad? The average US citizen produces about 4 pounds of landfill waste per day. Mix in half a dozen CFL's per year with the trash of an average household, and the amount of mercury ends up being about the same as natural occurs in the earth's crust.
Again, you don't have to believe me, but if you search around for the relevant information (natural abundance of mercury, trash produced per capita, USDA recommended limits on tuna intake, EPA datasheets on mercury and methylmercury, etc) you can verify everything I just wrote.
The tubes are recycled. I used to to do that job a long time ago. Basically, you have a grinder that is fitted to a lid for a 55-gallon steel drum. The grinder has a feeder tube, you just shove the tubes into the feeder, they get ground up into the 50-gallon drum, and it is classified a solid low-level mercury waste and sent off to the reclamation facility.
So yes, CFLs could get into the same waste stream as for the tubes. But it costs money. The party with the burned out tubes pays for it.
Edith Keeler Must Die
PWM (Pulse Width Modulation - Highly efficient brightness control) can go at 200khz or more.
No matter how much you whine, you cannot see that.
If you can, then your only deluding yourself that you can.
No kidding.
Just look at Minamata (methyl mercury) and the tragic story of Karen Wetterhahn (dimethyl mercury).
I was testing LEDs today, and one in particular impressed me. It lit up my (very dark) cave
like daylight. Not blue, not yellow. It has 36 LEDs dotted around it, so it isn't in the
classic bulb form.
This is a similar one (Chinese products; could be countless copies):
http://evilidler.webofcrafts.net/S660E27-36D.jpg
One thing that should be remembered about the current regulations for mercury are very strict in contrast to the levels associated with deterministic effects. This is perfectly natural since the natural occurrence of mercury is in such low concentrations. In fact almost all practical problems with mercury and how to deal with it are somehow linked to the inability to accurately measure it at the concentrations it begins to harm organisms.
Second, the speciation (division between different compounds) of mercury makes a huge difference in how the body absorbs it. The elemental form, found in old thermometers, switches and these CFL's, is practically biologically unavailable when liquid. There was a man in Taiwan who drank, IIRC, around a kilo without permanent effects. Oxidized mercury (HgCl2, Hg(NO3)2, and a few others) are also generally quite unavailable--several were used as syphilis medicine for quite some time--but led to a number of occupational hazards and poisonings. Mercury sulphide, on the other hand, is so unavailable that it's considered a "retirement path" in the mercury cycle. Among the variety of questionable Chinese medicine are "herbal balls," which have been found to contain up to 1.2 g (over a hundred CFL bulbs worth of mercury) of HgS. Finally, there are organic mercury compounds which are extremely toxic, but these are irrelevant except when they are produced by man in large quantities (though not necessarily on purpose) or when large amounts of inorganic mercury are available to anaerobic bacteria.
Almost all large-scale mercury poisoning has been due to the organic form entering the food supply.
However, though elemental, the form found in CFL's would most likely be vaporized if it got loose in your home. Vaporized elemental mercury is readily absorbed into the lungs, and can cross the blood-brain barrier, leading to temporary neurological effects in the few well-studied cases of household aspiration of the elemental form. Irritability and hyperactivity are typical symptoms.
Five milligrams is a good round number for the Hg content of a single CFL bulb. What is that for a person? 0.1 ppm? Well, the onset of symptoms in the victims of the Minamata disease (organic mercury poisoning) was a hair concentration of around 50 - 125 ppm (as mentioned, the margin of error on everything related to mercury is HUGE). Ca 100 ppm blood concentrations were found in the mothers of newborns in Iraq after an incident there with fungicide-laced grain in the 1970's. Again, uncertainty is the rule, and due to widely-varying affinities for heavy metals between different organs, there's very little one can predict in a given incident.
On a side note, while doing my thesis on a power plant mercury control system, I found my first grey hairs.
Check this out:
http://www.superbrightleds.com/cgi-bin/store/commerce.cgi?product=MR16
They have bulbs ranging in brightness from $8 to $50. I've seen this site before, but never tried out the bulbs. $50 seems a bit much, but I might go for one in the $20 range and see how it works in my desk lamp.
Single LEDs without phosphor coating are moderately narrowband. Phosphor-coated LEDs can have a smooth, broad spectrum like daylight, as can a combined assortment of LED colors. Varying the chemistry of LEDs allows them to be tuned to any visible peak wavelength.
Contribute to civilization: ari.aynrand.org/donate
100 microseconds every 10 miliseconds is only 100Hz. I'm not sure why car makers use such a low frequency, but I can see it as well and it is kind of distracting. I can also see colors in DLP projectors and TVs if I move my eyes quickly enough.
I'm using a homemade LED light as a desk lamp right now, and I can't see any flicker. The PWM chip controlling the voltage is running at around 300KHz, and I can dim it all the way to zero without any flickering. Even if it was running at a lower frequency, the filter capacitor is smoothing the voltage.
I used a 95 lumen Luxeon Rebel Star for the LED (but you can get up to 180 lumens with no additional power used) and a MAX774 for the PWM. The total cost was under $40, and it is at least as bright as a 15W halogen light. I took the circuit from a Maxim application note.
Sunlight is pretty darn smooth, but it's not really necessary to emulate sunlight.
When you dim the lights for a cozy mood, you are trying to emulate firelight or candlelight - not sunlight. Dimming CFLs just get dimmer and dimmer, not redder and cozier. The effect is somewhat like leaving your LCD monitor on in a dark room - not a warm candlelight.
Here's a neat site that lets you see the actual spectrum of all these things...
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
In 2005, coal-burning electric plants emitted 45 tons (=4.5E7 grams) of mercury in the US. That year the electric power production in the US was just over 4 billion Megawatt hours (4E12 kW-hr), so the emission is 1.1E-5 grams = 11 micrograms per kilowatt hour.
A 60-watt bulb that is on for typically two hours per day uses 44 kW-hours, so the emission of mercury due to such a bulb would be about 480 micrograms per year; or roughly 5 milligrams per ten years.
A 60-watt (equivalent) CF lightbulb has (by EPA standards, "no more than") 6 mg of mercury in it. If it is 4 times as efficient as an incandescent, it emits 120 micrograms per year, or 1.2 milligrams in 10 years. So the difference in mercury emissions is 3.6 milligrams in 10 years. So if the bulb lasts 17 years or longer, it would emit less mercury than the CF bulb.
The expected life of a CF bulb is between 6000 hours and 15,000 hours (between 8 and 20 years, at 2 hours per year), so overall, if you credit the lifetime figures, the mercury emission is roughly a wash.
The exact break even point depends on what fraction of the electrical power where you live comes from coal, as well, and whether the coal plants have scrubbers. (the numbers above are average for the US, where electricity is about 50% coal, in 2005)
Whether it's break-even or not over the lifetime of the bulb does not depend on how long you burn the bulb per day, except that CF bulbs last longer if you burn them longer-- so if you leave your bulbs on all the time, you get longer life from them.
(Unfortunately, I don't much credit these predicted lifetimes. The lifetime of a CF bulb drops the more often you turn it on or off, and my guess is that these lifetimes are for bulbs that are never turned off, not for typical household conditions nor for ratty NEO power. It's also quoted for "brand name" bulbs, not the cheapo ones you buy at the dollar store. If your CF bulb has an EnergyStar rating, by law it's guaranteed for two years. So you should keep a logbook of every time you replace a light bulb, so you can get your five dollars back, and you can email the EnergyStar program at cfl@energystar.gov to tell them about it.)
This reference goes through basically the same calculation.
http://www.geoffreylandis.com
As someone who works on the equipment that they use as part of the manufacture of LEDs... let me just say that they aren't exactly manufactured with durability in mind. They actually turn off some of the quality-control circuitry on the assembly machines because it is cheaper for them to plow through a batch and ruin it then it is for a guy to come along and see what the machine is complaining about. To be honest, they'd probably just run the ruined stuff through the machine again. These things are pumped out by the gazillion in the absolute cheapest possible conditions in China.
Of course, they are still too expensive even with all that, so there will have to be some change in technology before they are used in mainstream lighting applications. Well, that and they look horrid.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
You might have to buy a special fixture to handle it... But, I'd reccomend finding a circline CFL or a really bright CFL from www.buylighting.com They got a 100watt CFL there. Puts out around 6000 lumens of light in the warm 2700k color. Still not quite the same as the 22000 lumens that a halogen will put out. But, it should be more than bright enough to light a room. If all else fails get 2 or 3 of them. You'll be pumping out the same light for 1/3 the price in power.
.20 an hour to use it. If its in a room thats used frequently you are probably paying about 10 bucks a month to use it. The price of a typical Satellite radio service.
Also, 1000w bulbs only last about 2000 hours compared to 10,000 hours for the CFL.
Think about how much that Halogen costs you in power...
At california prices you'd be paying at minimum about
The service life of CFBs and regular bulbs makes me suspicious. CFBs do not last much longer than incandescent bulbs used to. I've had 2 of 12 burn out over a year or so despite the 5 year promise on the box. Incandescent bulbs used to be that good and halogen incandescent bulbs still last longer than CFBs. Ask yourself when the last time you changed your car headlights was.
There are big quality differences between manufacturers. I converted much of my home lighting to CFBs when they first appeared several years ago; all of the GE or Philips bulbs are still burning 6-7 years later (including a couple I've left on continuously), whereas all of the 'Feit Electric' bulbs (a brand sold at Costco in my state) burned out within a year or so.It pulls 4W, costs a bunch and lights up better than the 60W I use for outdoor lighting.
The price list I've seen has them near $6 apiece (bulk purchase). After all the
middle-men have taken their cuts, expect those six dollars to reach double digits.