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Plasma Plants Vaporize Trash While Creating Energy
Posted by
samzenpus
on Thu Nov 13, 2008 01:14 AM
from the Mr.-Fusion dept.
from the Mr.-Fusion dept.
Jason Sahler writes "Recently St. Lucie County in Florida announced that it has teamed up with Geoplasma to develop the United States' first plasma gasification plant. The plant will use super-hot 10,000 degree Fahrenheit plasma to effectively vaporize 1,500 tons of trash each day, which in turn spins turbines to generate 60MW of electricity — enough to power 50,000 homes!"
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Submission: Plasma Plants Vaporize Trash While Creating Energy by Anonymous Coward
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Environmental impact? (Score:5, Interesting)
Most of what we produce, most 'trash' is going to be hydrogen, carbon, and oxygen. So I have to wonder, is this 'burning' it, or is it going to be producing diatomic hydrogen and oxygen? Does anyone have any experience with plasma gasification that could explain why this wouldn't produce unwanted byproducts from the gaseous components cooling down?
Re:Environmental impact? (Score:5, Funny)
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Re:Environmental impact? (Score:4, Funny)
Oxygen is good.
Oxygen was invented by Shampoo.
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Re:Environmental impact? (Score:5, Interesting)
You got it. Supposedly at those temperatures, no molecule complex enough to be harmful will survive.
Of course, that doesn't much help with any metals that happen to get vaporized in there with it... but everyone needs a little more zinc in their diet anyhow.
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Re:Environmental impact? (Score:5, Insightful)
That's fine, but what about when you reach the end of the process and the atoms/molecules start to cool down? Unless you separate them out, they're going to start to react.
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Re:Environmental impact? (Score:5, Informative)
Yes, they seperate the bad stuff out. From TFA:
The intense heat of the plasma gasifies municipal waste, converting it into "syngas", which is then cleaned to remove volatile elements.
This process is not new -- it's been done elsewhere (Japan, Canada, UK) before. It works. They know what they're doing.
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Re:Environmental impact? (Score:5, Informative)
Aren't there plenty of simple molecules and elements that are toxic, not just metals?
Most elements are only toxic when part of specific molecules. They're toxic because they're highly reactive, and reaction means they're going to a lower energy state. At some point, the energy state should become low enough that they're pretty inert.
Ofcourse stuff that's toxic because of radioactivity instead of chemical properties is a different matter. But if you vaporize it and mix it with lots of inert material, you should end up with something that's about as radioactive as sea water.
We should focus on reuse and recycling, not vaporization.
Of course, but recycling isn't always practical.
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Re:Environmental impact? (Score:5, Informative)
1. Garbage contains a lot of energy (hydrocarbons in plastics, rubber, food, paper, etc).
2. Garbage contains some metals (aluminum, iron, copper, zinc, nickle, etc).
3. Garbage contains a far amount of inert material (earth, ceramics, etc).
So, you run everything through a big grinder, feed the dust to an electric torch which turns it into plasma, which of course breaks all those fancy compounds down into simpler elements:
1. Hydrocarbon gas - synthgas (methane like stuff).
2. Steam -- the water trapped in plant materials mostly (grass clippings, banana peals, stuff like that).
3. Metallic gas - which you can optionally separate by element if you have the right equipment.
4. Slag - inert silica mostly, mixed with other crud (which you can use as building materials).
Important thing to remember is the electric torch doesn't burn the garbage -- burning is inefficient and pointless. You want to separate all the various elements so you can make efficient use of them:
1. The hydrocarbons are pull off as synthgas, which you use some of to run a generator to power the torch and the surplus you sell to a conventional natural gas power planet for profit!
2. The steam which you separate and sell to as heat for commercial or residential use.
3. The metals you sell as scrap -- either high or low quality depending on your ability to separate the elements from the plasma.
4. The silica slag you can mold into pavers while it's still hot, or spin into a ceramic like wool as insulation, or into black pebbles as ground cover or whatnot.
The process has a number of advantages:
1. It is profitable -- it produces more energy than it consumes.
2. It's low tech -- you can set up the facility inside the garbage dump and avoid shipping the garbage around.
3. It sterile -- it consumes medical waste, contaminated material, toxic junk as readily as normal waste and it reduces it all to simple lemony fresh clean compounds (makes the birds sing). You can't feed it radioactive material obviously, as that would foul up the works.
4. It's happy -- converts garbage back into useful things.
Biggest obstacle has been the patents on the process which expired a year or two ago. Rejoice, garbage is the new valuable resource!
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Sunshine (Score:5, Interesting)
If ever the whatcouldpossiblygowrong tag were appropriate...
Re:Sunshine (Score:5, Informative)
What could possibly go wrong? I dunno, lots of things. The whole place could catch on fire. Or someone could be electrocuted by equipment on site. Or someone has an accident on a ladder and falls and hurts himself. Or gets in a car crash on the way to work. (That's probably the most dangerous risk right there!)
What, you wanted something exotic? 5,600 degrees C is weak. A lightning bolt can hit 30,000 Kelvin. Somehow the Earth escapes destruction though!
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seems a bit stingy (Score:5, Insightful)
1.2 kW per household? A hair dryer eats more than this.
You keep your dryers on 24/7? (Score:5, Insightful)
Do not confuse power and energy.
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Re:seems a bit stingy (Score:5, Funny)
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Technically true... (Score:5, Informative)
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Recently? (Score:4, Funny)
Yes, they recently announced that... Just a few couple after the first slashdot story, where they announced it:
http://hardware.slashdot.org/hardware/06/09/10/0026243.shtml [slashdot.org]
The Doc is Back! (Score:5, Funny)
No longer will I need Plutonium to generate the 3.3 Jigawatts nessecary to power my Flux Capacitor.
Artificial limits on power output (Score:5, Interesting)
From working with a garbage to energy plant in Virginia, they had the ability to generate much more then the 80MW (from memory) they were generating. They had to impose the limit or they would qualify as a utility under the state guidelines, and be subject to regulation. Since the plant was privately owned, and wanted run themselves, they had to let a lot of the power go as heat.
They would regulate it some by the rate at which the garbage went in, but when it starts backing up, you have no choice but to burn it.
Re:Artificial limits on power output (Score:4, Insightful)
Too bad they couldn't have had a water tap run to their place and use the excess energy to make hydrogen through electrolysis. And than sell said hydrogen. I mean, if it's free energy...
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Vaporware technology (Score:5, Informative)
Their web site [geoplasma.com] just screams "vaporware". In fact, the useful-scale project has been cancelled [tcpalm.com], and only a small "demonstration plant" will be built.
The real questions about this are 1) do they really get out more energy than they put in, and 2) how much processing of the exhaust gases is required? Westinghoue Plasma Corporation [westinghouse-plasma.com] (which, sadly, has little to do with Westinghouse) claims that 1000 tonnes (metric?) of solid waste produces the energy equivalent of 1 (one) barrel of oil. So this isn't a big energy producer. Ordinary waste-to-energy plants do better than that, but don't burn as clean as a plasma arc.
The other problem is what comes out. Organic compounds are literally blasted apart into atoms at those temperatures, so it deals with biowaste just fine. CO2 comes out, of course. NOx, maybe. Everything heavier (metals, etc.) is supposed to come out as a "molten slag" suitable for cement aggregate. Not sure what the cement industry thinks of this. They're usually quite picky about what's allowed in cement aggregate [cement.org]. Some contaminants interfere with the chemistry of concrete curing and make bad concrete. It might be good for filling in swamps and such.
Re:Vaporware technology (Score:5, Interesting)
Their web site just screams "vaporware". In fact, the useful-scale project has been cancelled, and only a small "demonstration plant" will be built.
To respond to these two points.
1. This is an established technology, even though it hasn't been commercial for all that long.
2. A lot of projects are being cancelled as collateral damage from the mortgage meltown.
To respond to the rest of your post:
http://science.howstuffworks.com/plasma-converter.htm/printable [howstuffworks.com]
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Reading and visualizing (Score:5, Funny)
Still asleep here, so my visualizing of this was:
"Plasma " ok that's the hot stuff
" plants " O, the beautiful trees, the nature... hmm, wait a second. Plasma trees? plasma grass?! What the...
" Vaporize trash " Dear freaking gawd! trash vaposizing red hot trees?!? Scorching grassy plains to vaporise trash on?
" While creating energy " They are self sustaining?! It's the end of the world! We're all gonna diiie!
Could work. (Score:4, Insightful)
It seams reasonable that a technique like this could get net energy out, since it's essentially a fancy trash burner. There's plenty of energy in trash to extract.
The slag could be interesting, though. It will few full of evilness and heavy metals. It probably won't be worse than landfilling since the evilness would otherwise be dumped in the same quantities. I'd be suprised if it was useful for construction. I'd expect water based leaching etc to erode the internal structure of it pretty quickly to a point wherre it's a porus, crumbly rock. I may be wrong about that, though.
Also, it might be easier to refine the slag, since a lot of the annoying bulk waste has been removed.
OK - I'll bite (Score:5, Informative)
Re:OK - I'll bite (Score:5, Funny)
I do a LOT of work on refuse disposal options, principally for the UK food industry
A back of the metaphorical fag packet calculation
Oh, you brits and your wacky words and silly sayings. As a yank, I never cease to be amused by it.
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Re:So.. (Score:5, Informative)
How much energy is used in generating that 10,000 degree plasma, hmm? Less than what it'll output by incinerating trash? I'd like to see that.
It's apparently self sustaining [tech-faq.com].
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Re:So.. (Score:5, Informative)
It is self sustaining in the way your car's electrical system is: It provides enough juice to start the engine, which recharges your battery and runs your radio/lights/cigarette lighter.
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Re:So.. (Score:5, Interesting)
exactly. it's unlikely that the initial electric charge will require more energy than is produced by the 1500 tons of garbage it burns each day (and presumably the plant stays on for more than a day at a time).
though i think a diesel engine is perhaps a better analogy since normal gas ICEs need an electrically-generated spark for each cycle, whereas a diesel engine uses compression-ignition thus only requires electricity for the initial compression stroke, after which point the engine is self-sustaining. so in this case the trash being vaporized is like the diesel fuel which is capable of sustaining the reaction on its own once the process is started.
in any case, this sounds like a great way to kill two birds with one stone. so long as the plasma plant doesn't generate any toxic waste or cause heat pollution it'd be a great way to get energy in practically any environment. now we just need to get more plug-in electrics on the road so that our transportation infrastructure can take advantage of cool sustainable technologies like this.
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Re:Your High School Physics Teacher Called (Score:5, Insightful)
I think you're seeing this from the wrong angle. The trash is "fuel" for the turbine. Think along the lines of coal burning power plants. The coal isn't free, it's a resource that is used to create electricity. I don't see how burning trash would be that different?
The article is offline right now.. so i'm really just guessing here. But the purpose of the plant isn't just another powerplant, it's a trash removal plant as well.
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Re:Slow down... (Score:5, Funny)
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Re:Slow down... (Score:5, Interesting)
I hate to be that guy on /. who can't take a joke, but... brine shrimp have a really important niche role in the food chain. This is a bit of an oversimplification, but basically without brine shrimp and things like it, there would be none of the larger tasty fish that we like so much to eat so much. This is why it drives conservationists nuts when people bitch and moan about environmental regulations aimed at protecting something which seems insignificant to the layperson. You fail to see the interconnectedness of it all.
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Conservation of energy (Score:5, Insightful)
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Re:Conservation of energy (Score:5, Funny)
See, this is my problem with you people who put all your faith and belief behind "science", it just leads to pessimistic attitudes. I mean sure, I know it's unlikely that this system would be the exception to conservation of energy or any other principle of physics, but there's always a possibility that maybe, just maybe, plasma garbage vaporizing is where physics breaks down. So, if you want, I'll let you live in your miserable world where you're always right and nothing exciting ever happens. All I ask is that you just don't disturb me in my world, a world of imagination and possibilities, a world where anything can happen, a world where flying cars, jetpacks and sophisticated sex robots are just around the corner and yes, a world where garbage vaporizes can run amok, producing more energy than is put into them thereby destroying the universe. Screw your science, that's the world I want to live in.
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Re:Conservation of energy (Score:5, Insightful)
These are the kind of energy the world has to seriously consider. Something that solves one problem (reducing the amount of rubbish that ends up in landfills), while also producing useful energy.
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Re:Conservation of energy (Score:5, Funny)
Screw your science, that's the world I want to live in
I am intrigued by your rant and wish to subscribe to your spam.
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Re:Conservation of energy (Score:4, Funny)
Because they don't have open minds.
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Re:Conservation of energy (Score:5, Insightful)
Why is it that so many people do not understand the difference between "an open mind" and "a hole in the head"?
A relevant quote I once encountered is: "You need to have an open mind to let new ideas in, but not so open that your brain falls out."
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Re:Conservation of energy (Score:5, Insightful)
About the "scientific consensus" : for starters, that is a very ill-defined concept. Second, the scientific consensus was once that the titanic was unsinkable, that the earth was flat, and that some cool looking naked bearded guy in the clouds threw lightning at ill-behaving children.
Your post is so astoundingly wrong that I don't really even know where to begin rebutting it. You start off with a plausible (even if the numbers are completely made up) premise, but then just go on about how we can't trust anything. Not sure what your point is, but it seems to be that since there is always doubt, we shouldn't go with ideas that you disagree with. That generally seems to be the "conservative" position lately. If the science supports what you want to do, shout it from the mountain tops. If it doesn't, bury it and do what you were going to do anyway.
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Re:Conservation of energy (Score:5, Insightful)
Are you saying there's no energy in garbage? I have a box of matches here that says you're wrong.
The theory behind it is this: If you can take the garbage molecules apart and put them back together in a lower energy configuration then you get to keep the profit.
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Pyrolysis may be more useful (Score:5, Informative)
One of the problems we are going to face Real Soon, is "Peak Oil". Another is funnily enough "Peak Soil"[1] and yet another is too much CO2 in the atmosphere.
A plasma turns everything into the basic element and from there to the lowest energy state, so yeah we get plenty of energy out, but it doesn't help so much with peak oil, peak earth or too much co2 in the atmosphere.
Some of the benefits of pyrolysis however:
1: Energy is produced.
2: Liquid fuels can be produced for transport.
3: Biochar/Agrichar byproducts can be used to improve agricultural soils.
The biochar byproduct can make the process carbon negative.
[1] Degradation of agricultural soils.
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Re:Pyrolysis may be more useful (Score:5, Insightful)
The reality is that we don't have enough planet for everyone to be a meat-eater, at least not in the American sense. For every 100 pounds of grain protein you give to cattle as feed, you only get back 10 pounds of protein as meat. So although American cattle typically spend their lives in a feedlot rather than on arable land, the fact still remains that that land must be used to grow grain to feed the cattle. We could support roughly 10 times more people with the same amount of arable land if everyone was vegetarian.
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Re:Pyrolysis may be more useful (Score:5, Insightful)
This is why we don't have enough planet for everyone to be a vegetarian.
uhhh... math fail.
very few of the animals you eat are grazing animals. exceedingly few. the amount of land it takes to graze an animal is huge. These cows are many hundreds of pounds, they need many more times that in feed. I would bet that very fiew of you could find anything in your markets that is not from an industrial (even organic industrial) farm. Whole foods doesn't have local farm food.
The animals are eating vegetation (the lucky ones) and are converting that into something you eat. that is a lossy process. the closer to the source (the sun) you are in the food chain, the more efficient.
I don't recall the exact numbers but the theory is along these lines. Sun shines energy, plants collect this energy and some local molecules and arrange this into a food like substance. This food substance now has (lets say) 20% of the energy that was put into making it available. Now we can eat that or we can let cow-creature eat it. Cow-creature converts it into a fabulously juicy steak for me. Negating any processing/picking/butching/carting/etc the sum of cow-creatures meat has approximately (again, lets say) 20% of the energy that it has consumed available to me in that yummy slab of flesh.
That leaves me getting about 4% of the initially available energy (100*.2*.2) whereas I could have gotten 20% had I eaten the damn carrot (or more likely, corn).
Like I say, numbers are off but no matter what numbers you substitute, you are never going to get out even the same amount of energy that went into making your animal.
As to your land argument, not only do you need space for the animals to live but you have to grow X% more food (and use X% more land) to feed them to get the same amount of food you would have needed.
hey, i like meat but it is not environmentally friendly.
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Mod the above post up. (Score:5, Interesting)
As I remember, farm raised catfish and free-range chickens get a 1:1 corn-protein to meat-protein ratio, mainly because they also eat bugs (or in China, the catfish/shrimp eat chicken poop.)
For cows, I think the number was either 8:1 or 20:1.
So yes, the poster who suggested that this is why everyone can't be a vegetarian is wrong. But I don't put it down to math. I put it down to his spouting off without having any actual facts.
Just as an aside, I might mention that this plant will likely poison the ground around it with such things as cadmium (NiCad, NimH batteries), mercury (coin batteries, thermometers... hospitals burn these up all the time), lead, arsenic, and other heavy metals.
The real shame is that a lot of these heavy metals actually should be classified, like gold, as precious metals. Right now when we are in deflation (with a specter of possibly hyperinflation once the credit bubble has burst), those metals are one of the few things that will maintain value.
I'd think that a few chemists who sat down and found a way to properly reclaim the lithium and other metals, could make a killing by collecting and sorting the waste, and then disposing of the non-toxic waste in standard ways, while mining the waste for all it's worth. The earlier you sort it, the higher your profits will be. Sorting a NimH from a NiCad will save a lot of extra effort and energy on the back end.
Then, as you identify more wastes (and the typical condition that it arrives in), then you can figure out a way to profit from that, too.
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Re:Pyrolysis may be more useful (Score:5, Insightful)
We have way more arable land than we do water to irrigate it. It takes 50x as much fresh water to grow a pound of beef as a pound of rice or soy beans. The fresh water constraint will bind long, long before we ever run out of places to grow or graze--in fact it's already being reached in the developing world. In your terms, we could stretch this planet a lot further as vegetarians than as omnivores.
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Re:Conservation of energy (Score:5, Funny)
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Re:Conservation of energy (Score:5, Interesting)
This process will NOT "create" energy. In fact, I doubt it will have any more efficiency than the current conventional methods of turning trash into useful components. Keep in mind that vaporization of any solids from room temperature it going to take a massive amount of energy. Spinning turbines with the gasses until it condenses is an obvious step to take, but there is a lot of legislation that can be made to supplant the need for more technology. Just take a look at Germany. You can get a hefty fine for putting a can in the bio-degradable receptacle, but those guys have one helluva disposal system.
Way to have no idea what you're talking about. I've read several articles [popsci.com] on this process and the man behind it.
Yes, it takes a lot of energy to start the reaction and form the initial plasma. Once it is started, however, as long as it is fed fuel (garbage, or any compound matter), the reaction will continue. The process completely breaks apart whatever is fed to it into its elementary components, thus effectively neutralizing virtually every known toxin and hazardous substance, the only exception is radioactive elements which cannot be broken down any further without undergoing a nuclear reaction.
Regarding energy output, this method produces energy in the form of heat from the plasma itself which can be harnessed and it produces syngas. Both of which are useful. this process has been in trials for some time now and has been proven to work. The reason everyone isn't running to it is that the plants are expensive to build, and never been done wide scale before. It's a new tech that the people with cities to run and people to protect are dubious about. New York and Ottawa Canada both plan on having plasma gasification plants, afaik.
Think of it like a really big fire. To start a fire a lot of initial energy is needed. Once it is started, it will keep going as long as it has fuel. The bonds in all molecules contain energy. This process breaks those bonds and release the energy and the result of the process is salable, environmentally friendly materials.
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Re:Conservation of energy (Score:5, Interesting)
I was thinking exactly the same thing - I'm still sceptical, certainly, but the Scientific American story [sciam.com] that's linked from the one above does say that "it will process 1,500 tons of garbage a day, sending 60 megawatts of electricity to the power grid (after using some to power itself).". They're definitely trying to claim that they've found a way to use random waste as a fuel source, which would be a breakthrough if true.
What worries me is a quick Google of the company. One of the top links is this [blogspot.com] interview with the company president. The fact that he keeps talking about "megawatts of energy per hour" puts my cynicism into overdrive - sure, it's not entirely damning; maybe the engineers are sitting hanging their heads at how the president doesn't understand what they're doing, but when the likelihood of their claims actually being what they say they are is this low, that really isn't who they need at the helm.
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Re:Conservation of energy (Score:5, Interesting)
I was thinking exactly the same thing - I'm still sceptical, certainly, but the Scientific American story [sciam.com] that's linked from the one above does say that "it will process 1,500 tons of garbage a day, sending 60 megawatts of electricity to the power grid (after using some to power itself).". They're definitely trying to claim that they've found a way to use random waste as a fuel source, which would be a breakthrough if true.
Using random waste as fuel source has been done already. Using random waste as a clean fuel source, now that's really a breakthrough. And if this process works the way I think it does, it should be pretty clean, no matter what you throw in.
Except for CO2 probably, which is kinda hard to prevent, and rather a big issue lately. I hope they can capture it in something safe. And if they can't, well, CO2 is still quite a lot better than dioxins.
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Re:"While Creating Energy" (Score:5, Insightful)
I have some doubts about it producing more energy than it uses, but it could because it is not an isolated system - you keep adding trash
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Re:supertoxins? (Score:5, Informative)
You are right, and I think that's one of the reasons they are proposing plasma (look it up... [wikipedia.org]). In that state of matter, all molecules break up, including dioxin and other poisonous compounds. However, what happens when you cool down the exhaust gases will depend a lot on the construction, so you might still get dioxin (or something worse than that); I suppose this is fairly implementation-dependent. Also, I am not so sure about what happens to particulate: does the cooling process create more of it, or does the plasma state break it down?
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Re:Summary, pt. 2 (Score:5, Insightful)
If you count landfill products as free fuel, then you're generating something. You're turning something that is unwanted into something valuable.
If you collect solar energy, you're not creating energy. You're turning those photons into something more useful than heat and reflected solar radiation.
I think a lot of people commenting on this article have a weird definition of generator/generation.
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