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RE: Nuclear fusion - 7/21/2008 9:46:53 PM
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Bettawrekonize
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quote:
ORIGINAL: essentialsaltes
My guess is that, like with antimatter, the problem with hydrogen peroxide is that it doesn't grow on trees, or bubble out of the ground.
So, how much does it cost to produce hydrogen peroxide?
According to this website
quote:
In large quantities, 95 per cent hydrogen peroxide then cost approximately $1.00 per kg.
http://www.astronautix.com/props/h2o2udmh.htm
and I doubt the energy yield per gallon is less than gasoline (probably more).
Hydrogen Peroxide is H2O2, it's just one hydrogen atom less than water.
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RE: Nuclear fusion - 7/21/2008 9:49:01 PM
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Bettawrekonize
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quote:
ORIGINAL: iluvatar
It's also been used to fuel torpedos. IIRC, an H2O2 explosion is what's thought to have sunk the Kursk.
Do you think it has potential. If not, why not? If so, then why hasn't it been commercially used much (since we seem to already have the technology to use it)? It doesn't seem that expensive to produce.
I also found this website interesting.
Hydrogen Peroxide Car Motor
< Message edited by Bettawrekonize -- 7/21/2008 10:01:33 PM >
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RE: Nuclear fusion - 7/21/2008 10:38:31 PM
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iluvatar
Posts: 1647
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quote:
ORIGINAL: Bettawrekonize
Hydrogen Peroxide is H2O2, it's just one hydrogen atom less than water.
One more Oxygen, not one less Hydrogen.
quote:
Do you think it has potential. If not, why not? If so, then why hasn't it been commercially used much (since we seem to already have the technology to use it)?
I have no idea. I do seem to recall that it reacts with certain metals - not a good quality for an everyday fuel.
-Dan.
_____________________________
Well, I've been to one world fair, a picnic, and a rodeo, and that's the stupidest thing I ever heard come over a set of earphones.
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RE: Nuclear fusion - 7/21/2008 10:51:41 PM
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gluadys
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quote:
ORIGINAL: Bettawrekonize
quote:
ORIGINAL: iluvatar
It's also been used to fuel torpedos. IIRC, an H2O2 explosion is what's thought to have sunk the Kursk.
Do you think it has potential. If not, why not? If so, then why hasn't it been commercially used much (since we seem to already have the technology to use it)? It doesn't seem that expensive to produce.
I also found this website interesting.
Hydrogen Peroxide Car Motor
Hydrogen cars are currently in use in Singapore. You can even fill up your hydrogen tank at the regular service station where there are pumps for hydrogen fuel. This is one of the examples of already existing green technology mentioned by Chris Turner in The Geography of Hope
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RE: Nuclear fusion - 7/21/2008 11:58:49 PM
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Bettawrekonize
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quote:
ORIGINAL: iluvatar
One more Oxygen, not one less Hydrogen.
That's what I meant to say. Sorry, it's been a long day.
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I have no idea. I do seem to recall that it reacts with certain metals - not a good quality for an everyday fuel.
Yes. It reacts with silver. In fact, you mix it with silver and it produces lots of energy. That's the whole point. I think there are some other things you can use as well (ie: catalase (which isn't a metal) which wouldn't be practical to use, and I believe other metals as well) and one of the websites I linked to mentions them, but I'm much too tired to think coherently right now.
< Message edited by Bettawrekonize -- 7/22/2008 12:05:28 AM >
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RE: Nuclear fusion - 7/22/2008 12:17:42 AM
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Bettawrekonize
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quote:
ORIGINAL: gluadys
Hydrogen cars are currently in use in Singapore. You can even fill up your hydrogen tank at the regular service station where there are pumps for hydrogen fuel. This is one of the examples of already existing green technology mentioned by Chris Turner in The Geography of Hope
What I'm talking about is kinda different. With an H2O2 car, you have hydrogen peroxide (which is basically water with an extra oxygen atom) and you separate an oxygen from the molecule and this creates lots of energy. You end up with just water and oxygen, which are both environmentally friendly. You can use this energy to power a car (a car specifically built to run on H2O2 of course). I guess one website I linked to says that it has half the energy density as hydrocarbon burning. Like I said, something similar has been done before, so there should be little problems making it commercially available (but safety, from my understanding, is a huge factor. Then again, just about any fuel has its safety issues to some extent).
< Message edited by Bettawrekonize -- 7/22/2008 12:40:27 AM >
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RE: Nuclear fusion - 7/22/2008 12:43:53 AM
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ianz
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quote:
ORIGINAL: DanJames
1: We will never use up all the oil or coal on the planet. We continue to find more and more sources of oil as the days go by. Presently, the United States is the most oil-rich country on the planet. Perhaps you'd like to explain the $4/gallon price then, and the increase in food prices as land is used to produce bio-fuels. Fact: oil, gas and coal etc are finite resources. (Either they form over millions of years or they were put here by YECs' God.)
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2: Probably not Speculation at best, and in the face of an international panel of scientists on climate change.
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3:We aren't polluting large tracts of land, the waste can be stored in fortresses, transported by vehicles that are themselves fortresses. If by "hundreds of generations to come" they still haven't found something productive to do with it, then they deserve it. You must be a politician. Only a politician could label nuclear waste as a resource for future generations!
Consider this (mildly tongue in cheek):
Here, future generation, here's some nuclear waste for you. Sorry, but the limits of lifespan and our knowledge mean we haven't been able to test its long term impacts with certainty. We made it anyway. Hopefully it's ok. It's only stored in barrels round the back of some decommissioned plants because we couldn't agree on permanent storage locations (NIMBY and all that).
Oh by the way, don't forget to replace the sarcophagus on Chernobyl every hundred years.
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I'd say stewardship is not the issue. If you were worried about stewardship, why wouldn't you be all for nuclear energy since it is by far the cleanest most bountiful source of baseline energy? I didn't say I'm not for nuclear fission. I would however prefer to see just a fraction of the resources required on minimising energy usage first. And I think it is flat out irresponsible to create problems for future generations for purely material benefit, whether by using up finite resource, creating massive rubbish piles because we can't be bothered to recycle or re-use, or through generating nuclear or any other form of waste.
Regards, Ian
Edit: removed quoted post to shorten it up a bit
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RE: Nuclear fusion - 7/22/2008 2:04:46 AM
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gluadys
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quote:
ORIGINAL: Bettawrekonize
quote:
ORIGINAL: gluadys
Hydrogen cars are currently in use in Singapore. You can even fill up your hydrogen tank at the regular service station where there are pumps for hydrogen fuel. This is one of the examples of already existing green technology mentioned by Chris Turner in The Geography of Hope
What I'm talking about is kinda different. With an H2O2 car, you have hydrogen peroxide (which is basically water with an extra oxygen atom) and you separate an oxygen from the molecule and this creates lots of energy. You end up with just water and oxygen, which are both environmentally friendly.
That sounds exactly like the cars Chris Turner describes. I attended one of his lectures once where he showed slides. There was one showing the water coming from the tailpipe of the car. These cars are already being made commercially in Asia.
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RE: Nuclear fusion - 7/22/2008 8:53:50 AM
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Real_Solitude
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quote:
ORIGINAL: essentialsaltes
Personally, I think solar is truly beginning to come into its own. Solar probably could never support current levels of American energy usage, but I think as oil/gas get more rare and more expensive, we will be forced to make do with less energy - and in that scenario, solar power could well support a large fraction of our needs in a sustainable manner.
Why couldn't solar provide all of our needs?
According to Wikipedia Earth is hit by about 3,850 zettajoules per year. This is versus a usage of 500 exajoules energy useage. So we have 3.85x10^24 versus 5x10^20. If we can manage to get solar with near 100% efficiency we would "only" need to coat .01% of the Earth with cells to fulfill all of our needs. I'll grant that this would be a massive undertaking, but depending on the lifespan of the panels used it could be worth the effort.
_____________________________
"Instead of feeling alone in a group its better to have real solitude all by yourself."
~Faye Valentine
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RE: Nuclear fusion - 7/22/2008 10:14:35 AM
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essentialsaltes
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quote:
ORIGINAL: Real_Solitude
quote:
ORIGINAL: essentialsaltes
Personally, I think solar is truly beginning to come into its own. Solar probably could never support current levels of American energy usage, but I think as oil/gas get more rare and more expensive, we will be forced to make do with less energy - and in that scenario, solar power could well support a large fraction of our needs in a sustainable manner.
Why couldn't solar provide all of our needs?
I think I was playing within the bounds of the OP's "in the forseeable future". I think current mass-produced panels have a conversion efficiency of only about 10-15%, so that would mean we'd have to pave nearer 0.1% of the earth (or 0.3% of the land surface). That's a small fraction, but still a huge area, something like 5 million square kilometers. Looked at another way, the total solar power currently generated is less than 0.1% of the global demand, so we need to increase the current installation by a factor of 1000. Producers are certainly cranking up production, but it'll take some time to get there.
_____________________________
"My object in all arguments is not to make any preconceived opinion of mine seem right, but merely to discover and establish the truth, whatever the truth may be."
-- HP Lovecraft, letter to Robert E. Howard 7/27-28/34
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RE: Nuclear fusion - 7/22/2008 10:17:08 AM
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Bettawrekonize
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quote:
ORIGINAL: gluadys
That sounds exactly like the cars Chris Turner describes. I attended one of his lectures once where he showed slides. There was one showing the water coming from the tailpipe of the car. These cars are already being made commercially in Asia.
Not exactly. The following describes Chris Turner's position
Tall Poppy Interview: Chris Turner
Scroll down to where it says
"In the book, you mentioned that you got to experience using a hydrogen fuel pump. Could you talk a bit more about that experience?"
For the physics behind what you're talking about, go to.
Physics 10 - Lecture 05: Radioactivity
Start at about 8 minutes and 35 seconds (8:35). What I'm talking about is kinda the opposite.
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RE: Nuclear fusion - 7/22/2008 10:28:27 AM
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Bettawrekonize
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quote:
ORIGINAL: Real_Solitude
Why couldn't solar provide all of our needs?
According to Wikipedia Earth is hit by about 3,850 zettajoules per year. This is versus a usage of 500 exajoules energy useage. So we have 3.85x10^24 versus 5x10^20. If we can manage to get solar with near 100% efficiency we would "only" need to coat .01% of the Earth with cells to fulfill all of our needs. I'll grant that this would be a massive undertaking, but depending on the lifespan of the panels used it could be worth the effort.
From my understanding, the highest quality (most expensive) photovoltaic cells only provide like (at most, if you're lucky) 25 percent of the energy that comes from the sun per unit surface area. That means, lots and lots of surface area would be needed to really get a substantial amount of energy from them.
For the physics behind this technology, youtube Physics 10 - Lecture 17: Quantum I through Physics 10 - Lecture 20: Quantum IV from UC Berkley.
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RE: Nuclear fusion - 7/22/2008 10:57:31 AM
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gluadys
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quote:
ORIGINAL: Bettawrekonize
quote:
ORIGINAL: gluadys
That sounds exactly like the cars Chris Turner describes. I attended one of his lectures once where he showed slides. There was one showing the water coming from the tailpipe of the car. These cars are already being made commercially in Asia.
Not exactly. The following describes Chris Turner's position
Tall Poppy Interview: Chris Turner
Scroll down to where it says
"In the book, you mentioned that you got to experience using a hydrogen fuel pump. Could you talk a bit more about that experience?"
For the physics behind what you're talking about, go to.
Physics 10 - Lecture 05: Radioactivity
Start at about 8 minutes and 35 seconds (8:35). What I'm talking about is kinda the opposite.
OK. I'm not a techno-geek and this is going past my limits of comprehension. Just sounded much the same to me.
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RE: Nuclear fusion - 7/22/2008 11:55:49 AM
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Embedded
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Betta,
There are problems with H2O2...
1. By my calculations it only yields about 3MJ/kg (mega-Joules per kilogram) of 100% H2O2. Compare to about 40MJ/kg for gasoline.
2. While it has the advantage of being easy to control in the reaction chamber, it is also difficult to store and handle.
3. H2O2 in high concentrations can form dangerous contact explosives when it comes in contact with hydrocarbons (oil and asphalt). This makes it a problem to use in lubricated machinery and makes cleanup of a spill or leak on the roads especially hazardous.
There are numerous other problems.
While it is certainly feasible in concept to use H2O2 as an automotive fuel I think the costs per gallon versus the energy yield and the other problems far outweigh its practical use.
The main "nice" thing about H2O2 is that its combustion products are simply water and oxygen. Once it reacts it is very very clean... it is before it reacts, or AS it reacts, that there is a problem.
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RE: Nuclear fusion - 7/22/2008 5:25:03 PM
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Bettawrekonize
Posts: 1424
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quote:
ORIGINAL: Embedded
1. By my calculations it only yields about 3MJ/kg (mega-Joules per kilogram) of 100% H2O2. Compare to about 40MJ/kg for gasoline.
Sources?
According to the sources I linked to, the opposite is true.
quote:
The result is about half the energy density of hydrocarbon burning, but the result is just water and oxygen.
Hydrogen Peroxide Car Motor
quote:
High energy output.
Directory:Hydrogen Peroxide as Fuel
quote:
2. While it has the advantage of being easy to control in the reaction chamber, it is also difficult to store and handle.
Sources?
According to the sources I linked to, the opposite is true.
Advantages
quote:
Stable storage.
Directory:Hydrogen Peroxide as Fuel
quote:
3. H2O2 in high concentrations can form dangerous contact explosives when it comes in contact with hydrocarbons (oil and asphalt). This makes it a problem to use in lubricated machinery and makes cleanup of a spill or leak on the roads especially hazardous.
There are safety issues, but I suggest you do more research so that you better understand the ramifications. Start with some of the links I provided.
< Message edited by Bettawrekonize -- 7/22/2008 10:02:04 PM >
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RE: Nuclear fusion - 7/22/2008 6:00:19 PM
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Method
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quote:
ORIGINAL: Embedded
Betta,
There are problems with H2O2...
I work with both 20% H2O2 and many different hydrocarbons. The hydrocarbons are much easier to deal with. Concentrated hydrogen peroxide can not come into contact with most metals, it causes serious burns, can explode with very little provocation, etc. It's a pain in the rear in any large quantities. Hydrogen would be a much better option than hydrogen peroxide, IMHO. Hydrogen can be produced from renewable energies through electrolysis, so that is a plus.
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RE: Nuclear fusion - 7/22/2008 10:02:41 PM
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Bettawrekonize
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Thanks Method. Do you have any sources so I can read up on it more? Like I said, there are safety issues involved and those would have to be worked out.
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RE: Nuclear fusion - 7/22/2008 11:54:47 PM
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mikeman2
Posts: 281
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quote:
ORIGINAL: ianz
quote:
ORIGINAL: essentialsaltes
quote:
ORIGINAL: mikeman2
But I hear solar is also harmful to the evironment. Specifically, developing the solar panels is problamatic in that it pollutes the environment.
This is true. In a few more years, we'll be better able to see what the trade-offs are.
There's a pretty simple solution to all this.
Use less energy.
Regards, Ian
PS I should add - I realise it's not as simple as just reducing energy consumption. But a heck of a lot could be saved through more efficient use.
I don't think you get it my friend, we have an energy crisis on our hands. In addition, we are using fossil fuels which may be destroying the planet as well as making terrorists like oil man Bin Ladin rich enough to be a problem in the world. Oh yea, and I forgot to mention the current Iraqi conflict that has continued since the 1990's and is currently bankrupting the US and it is all over oil?
I know the answer for many is to not drive SUV's but this is like putting a bandaid on cancer. We need viable energy alternatives as of yesterday!!
_____________________________
Man will occasionally stumble over the truth, but most of the time he will pick himself up and continue on.
-Winston Churchill.
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RE: Nuclear fusion - 7/23/2008 12:03:54 AM
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Method
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quote:
ORIGINAL: Bettawrekonize
Thanks Method. Do you have any sources so I can read up on it more? Like I said, there are safety issues involved and those would have to be worked out.
A lot of it is personal experience. I spilled just a little bit of 20% HP on my finger and lost the top layer of dead skin. That was 20% HP. I also lost about 10 ml of 20% because I dipped my pipette in too far. The metal tip ejector shed enough metal to catalyze the release of enough oxygen to drop the HP below the concentrations I needed. And if you mix it with the wrong stuff, what most of us would consider safe chemicals, it blows up. As you said earlier every fuel has it risks, but concentrated HP is an explosion just waiting for an excuse. It's too strong of an oxidizer. I think we would be better off using the oxygen in the air as fuel instead of trying to package it as a fuel.
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RE: Nuclear fusion - 7/23/2008 12:09:44 AM
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Method
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quote:
ORIGINAL: mikeman2
I don't think you get it my friend, we have an energy crisis on our hands.
If carbon release was not a problem then the solution would be coal and electric cars, and this could be slightly mitigated by carbon dioxide sequestration. Nuclear fission is still a viable option. I really think that coal and nuclear could fill the gap until renewable sources are a lot cheaper and more effecient.
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RE: Nuclear fusion - 7/23/2008 4:45:04 AM
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ianz
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quote:
ORIGINAL: mikeman2
quote:
ORIGINAL: ianz
There's a pretty simple solution to all this.
Use less energy.
Regards, Ian
PS I should add - I realise it's not as simple as just reducing energy consumption. But a heck of a lot could be saved through more efficient use.
I don't think you get it my friend, we have an energy crisis on our hands. In addition, we are using fossil fuels which may be destroying the planet as well as making terrorists like oil man Bin Ladin rich enough to be a problem in the world. Oh yea, and I forgot to mention the current Iraqi conflict that has continued since the 1990's and is currently bankrupting the US and it is all over oil?
I know the answer for many is to not drive SUV's but this is like putting a bandaid on cancer. We need viable energy alternatives as of yesterday!!
I don't deny there is an energy crisis. I said: it's not as simple as reducing consumption. BUT it would make a huge difference. Taking your own suggestion, swapping vehicles that do 15miles/gallon for vehicles that do 30-40miles/gallon would have significant impact on oil usage. Increasing recycling of oil-based products would too. Encouraging efficient use of electricity reduces the reliance for new electricity generation. It all helps. We are a greedy society and taking these steps are an important PART of the solution, as well as finding alternative energy sources.
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RE: Nuclear fusion - 7/23/2008 5:18:14 PM
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Embedded
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quote:
ORIGINAL: Bettawrekonize
quote:
ORIGINAL: Embedded
1. By my calculations it only yields about 3MJ/kg (mega-Joules per kilogram) of 100% H2O2. Compare to about 40MJ/kg for gasoline.
Sources?
According to the sources I linked to, the opposite is true.
According to the sources you linked to? I didn't see any basic arithmetic on known enthalpies of reaction. On of you sources isn' much more informative than a bunch of links to other sources (the PESWiki one). Using one of your sources H2O2.com
Which (depending on how you want to use the info there) lists several values for the enthalpy of decomposition of H2O2. I will use the value that gives the greatest enthalpy. Please note that I use enthalpy of reaction or enthalpy of decomposition because it represents the maximum theoretical useful work that can be extracted from the reaction (delta-H or DH). So...
Given an enthalpy of decomposition of DH = -26 kcal/mole for H2O2. (The negative sign means it is exothermic and gives off energy)
Note: This value is for 100% H2O2 one has to reduce the value
accordingly for less pure H2O2. At 50% concentration the DH is about 50% less than the 100% value. For the purposes here I will ignore reactions that do not go to 100% completion.
Back to it... The mole is useful for chemical claculations but not all that practical for physical calculations. I shall convert it to kilograms. H2O2 has a molecular mass of 34 grams/moe
(2*16)+(2*1)=34. I think we can also drop the negative sign because we are discussing magnitudes at the moment.
DH = (26 kcal/mole) * (mole/34 g) * (1000g/kg)
multiplying through and cancelling units we get:
DH = 765 kcal/kg
Now I will convert it from kcals to MJoules (kilocalories to megaJoules) because I find Joule to be more useful for physical calculations.
DH = (765 kcal/kg) * (4186.8 Joule/kcal) * (MJoules/1000000Joules)
again mulitplying through and cancelling units we get:
DH = 3.2 MJoules/kg = 3.2 MJ/kg
So the maximum theoretically available work from one kilogram of 100% H2O2 is 3.2 MegaJoules. This does not account for any inefficiencies or other losses.
If you want to you can convert it into BTUs or ergs or whatever per liter or per gallon or whatever. This is all standard high school chemistry and physics unit conversion. I can do this all day long (and often do) because it is second nature to me. For me it is not boring or difficult but trivial and necessary. Also before you complain about the slight difference between my original 3 and the later 3.2 it is because I used a slightly lower number (also from your sources) to convert.
Now lets see what the DH is for a kilogram of gasoline... according to the Wikipedia page on Gasoline under energy content it lists it as
DH = 44.4 MJ/kg
for regular gasoline. So it appears to me that gasoline packs more than 13 times the energy per kilogram (or per pound) than 100% H2O2.
I looked through your links and many of the sublinks and I found nothing that would make me understand it as the opposite. Could you be more specific?
quote:
quote:
The result is about half the energy density of hydrocarbon burning, but the result is just water and oxygen.
Hydrogen Peroxide Car Motor
Not sure where venomx got that impression but... the fact that it is posted on a site dedicated to half baked ideas should tell you something. Also... "half the energy density" means it has less energy per unit mass than gasoline. I also found it to be less... but much less than half... more like a thirteenth. That link does not support your claim.
quote:
quote:
High energy output.
Directory:Hydrogen Peroxide as Fuel
I know it has a high energy output... but so does sugar, so does horse manure, so does a sneeze... but how much and compared to what? So quoting something that says it has a high energy output is meaningless out of context.
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quote:
2. While it has the advantage of being easy to control in the reaction chamber, it is also difficult to store and handle.
Sources?
According to the sources I linked to, the opposite is true.
Advantages
quote:
Stable storage.
Directory:Hydrogen Peroxide as Fuel
That source that you quote again is glossing over the difficulties. While, yes, it is true that high concentration H2O2 is stable when properly stored it completely ignores what properly stored actually means. Regular gasoline has the similar properties but can be stored in a much wider range of cheap materials. H2O2 will decompose spontaneously (via catalysis) if it comes in contact with a very wide range of materials.. many of which are common and extremely difficult to avoid. Rust for example or just about any reactive material.
I hope you understand the role of catalysts. It is not "used up" in a reaction.
In any case the PESWiki site leaves off the difficulties. Though they do mention. "Over about 80% H2O2 (where H2O is the impurity), it is explosive and extreme mechanical shock or heat can set it off."
I think if you dig just a little deeper you will find that PESWiki is misleading you. You need to read just a little bit more than what you want to hear. You also need to be able to understand some basic chemistry, physics, and properties of materials.
quote:
quote:
3. H2O2 in high concentrations can form dangerous contact explosives when it comes in contact with hydrocarbons (oil and asphalt). This makes it a problem to use in lubricated machinery and makes cleanup of a spill or leak on the roads especially hazardous.
There are safety issues, but I suggest you do more research so that you better understand the ramifications. Start with some of the links I provided.
I did start with those links. Most of them are pretty poor on the details and long on the hype. I actually work with this kind of stuff and I know first hand how it can react. I have not tried every possible scenario but there is good enough evidence from the ones I have tried that high concentration H2O2 is nothing to be taken lightly. When using it we have to be extremely careful that everything it will come in contact with is the correct material and is spotlessly clean. Even fingerprints can be a problem.
If you drop the concentration down to, say, 50% then a lot of these hazards become much less of a problem. Then, however, you have only 50% H2O2... the other 50% is regular old H2O, and not very useful.
You might want to read: this page on safety and other properties (linked from PESWiki). They also mention on that page that 90% H2O2 yields only 2.6 MJ/kg (even worse than I calculated).
Also read:
Hazards on some of the hazards. That link is also a sublink off of the PESWiki site. It is as if the PESWiki people never read any of that information in depth or chose to ignore it.
To summarize: All of the sites you listed (and sub-sites), when properly read in depth, support what I was saying and refute what you were claiming.
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RE: Nuclear fusion - 7/23/2008 10:49:49 PM
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Method
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quote:
ORIGINAL: Embedded
So the maximum theoretically available work from one kilogram of 100% H2O2 is 3.2 MegaJoules. This does not account for any inefficiencies or other losses.
If you want to you can convert it into BTUs or ergs or whatever per liter or per gallon or whatever. This is all standard high school chemistry and physics unit conversion. I can do this all day long (and often do) because it is second nature to me. For me it is not boring or difficult but trivial and necessary. Also before you complain about the slight difference between my original 3 and the later 3.2 it is because I used a slightly lower number (also from your sources) to convert.
Now lets see what the DH is for a kilogram of gasoline... according to the Wikipedia page on Gasoline under energy content it lists it as
DH = 44.4 MJ/kg
for regular gasoline. So it appears to me that gasoline packs more than 13 times the energy per kilogram (or per pound) than 100% H2O2.
Thanks for doing the footwork, Embedded. The instability of H2O2 that I complained about could be worked out in some way. However, I really don't see how one could build a car with a 260 gallon tank for a trip of 500 miles. You would waste a lot of energy carrying around the extra fuel.
If we are going to be using a fuel that we harness chemical energy from we need to be looking for a fuel that we can oxidize with oxygen from the air, IMHO. Ethanol would be great if we could ferment something other than readily available sugars. Methane would be great if we could derive it from renewable sources. Hydrogen sulfide packs quite a punch when it is oxidized but the release of sulfates would be just as damaging as carbon dioxide, perhaps even more damaging (afterall, low sulfur deisel is less destructive than high sulfur deisel).
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I did start with those links. Most of them are pretty poor on the details and long on the hype. I actually work with this kind of stuff and I know first hand how it can react. I have not tried every possible scenario but there is good enough evidence from the ones I have tried that high concentration H2O2 is nothing to be taken lightly. When using it we have to be extremely careful that everything it will come in contact with is the correct material and is spotlessly clean. Even fingerprints can be a problem.
That's my experience, too. In my lab we handle methanol, ethanol, acentone, acetonitrile, and other highly flammable hydrocarbons like we do water, more or less. Concentrated H2O2 is a different beast altogether. Outside of the lab most people are familiar with the hydrogen peroxide at the local grocery store. That's like 2-4%. People have the wrong idea about it's stability.
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RE: Nuclear fusion - 7/23/2008 11:07:33 PM
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Bettawrekonize
Posts: 1424
Joined: 4/17/2005
Status: offline
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Thanks for the criticisms Embedded
quote:
ORIGINAL: Embedded
You need to read just a little bit more than what you want to hear.
...
I did start with those links. Most of them are pretty poor on the details and long on the hype.
I couldn't find many (changed in edit, used to say "any" instead of "many," but even the sites I linked to before do mention safety. I didn't find any criticisms on the grounds of energy input before this post, but energy input needed to produce H2O2 is an obvious criticism regardless and that's basically what I was asking about) sites criticizing the idea (I was hoping someone could link me to one, which is partly why I asked for sources) which is why I posted it here (so someone else can criticize it and give input). I will look into it more when I have time. I always like to put my ideas through criticism (and overcoming that criticism if possible) and get input from others before taking a position. Thanks again.
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To summarize: All of the sites you listed (and sub-sites), when properly read in depth, support what I was saying and refute what you were claiming.
I haven't claimed anything yet, I'm just asking for input.
< Message edited by Bettawrekonize -- 7/24/2008 1:44:55 AM >
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RE: Nuclear fusion - 7/24/2008 12:42:03 AM
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Bettawrekonize
Posts: 1424
Joined: 4/17/2005
Status: offline
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quote:
ORIGINAL: Embedded
You might want to read: this page on safety and other properties (linked from PESWiki). They also mention on that page that 90% H2O2 yields only 2.6 MJ/kg (even worse than I calculated).
I think you're missing the point here. The energy doesn't primarily come from the heat (though I did mention it does produce a lot of heat), the energy primarily comes from the pressure. The 2.6 MJ/kg is the amount of heat energy that it produces. The amount of energy it produces total is way more than that.
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Actually, it does not burn, it decomposes, with a release of tremendous energy, close to the energy per mole of H2.
http://peswiki.com/index.php/Directory:Hydrogen_Peroxide_as_Fuel
So, it releases almost the same amount of energy as hydrogen, energy that can be used. More interesting questions are, how much energy is required to produce it and where will that energy come from? How much does it cost to produce?
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I hope you understand the role of catalysts. It is not "used up" in a reaction.
Of course. That's the whole point. You mix H2O2 with a catalyst and you can use the same catalyst over and over to keep on producing more energy from more H2O2.
< Message edited by Bettawrekonize -- 7/24/2008 12:53:02 AM >
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