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Creating Hydrogen With (Very) Hot Water
Posted by
timothy
on Sun Nov 28, 2004 03:57 PM
from the nukes-get-you-in-hot-water-anyhow dept.
from the nukes-get-you-in-hot-water-anyhow dept.
carbonman writes "NYTimes is reporting that a public-private research team will announce on Monday that they have discovered a new technique to produce pure hydrogen that is far more efficient than conventional methods. The advance could be a significant development in attempts to realize the dream of the hydrogen economy in taking gasoline-powered vehicles off the road, and without releasing carbon dioxide emissions that are linked to climate change. It does, however, require the use of advanced high-temperature nuclear reactors, none of which have been built on a production scale before."
swiftstream adds a link to the same story at the no-reg Indianapolis Star, and summarizes the method as "electrolysis of very, very hot water."
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Very, very hot water? (Score:4, Funny)
Re:Very, very hot water? (Score:4, Informative)
That's why a pressure cooker works faster than an open pot. The increased pressure allows the water to boil at a higher temperature.
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Re:Very, very hot water? (Score:5, Informative)
Yes it does at standard temperature and pressure. If you were to increase the pressure it would require a higher temperature to vaporize, just as lower pressures require lower temperatures.
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Re:Very, very hot water? (Score:4, Funny)
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Re:Very, very hot water? (Score:5, Informative)
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Re:Very, very hot water? (Score:5, Interesting)
Is it possible to take this naturally superheated water and use it to create hydrogen more efficently?
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Re:Very, very hot water? (Score:5, Informative)
These "spots" of super heated water occur around what are called black smokers [amnh.org]. The magma, or more accurately, mantle, is drawn up at mid ocean ridges [agu.org] due to the top-cooled convection of which plate tectonics is a direct result.
Mid Ocean Ridges rarely heat water beyond 400 degress C, but even so there could be potential there, since it's already heated to a great degree, requiring less energy investment. Plus, there's tens of thousands of kms worth of MORs on Earth.
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Re: Microwave heating (Score:5, Informative)
It's an interesting apparent contridiction because the water seems already hot enough to boil, yet it does't until the container is moved.
Anyone care to explain why this is?
To vaporize, water needs something to form a steam bubble around. Coffee grounds, sugar, or ridges on a metal pot will work for this. But, if you heat up pure water in a smooth ceramic cup in the microwave, there isn't anything to induce it to form steam. Thus, when you spoon that instant coffee in, it explodes.
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Re:Very, very hot water? (Score:5, Informative)
While I can't verify the temperature that the water was at, I had an incident this weekend that indicates this super-heating is not too difficult.
I put a 2 cup pyrex measuring cup in a microwave for about 2.5 minutes. The water appeared very calm and didn't have any bubbles. But as soon as I dropped my tea-bag into the cup, the water flared up and began to boil very vigorously for a few seconds.
The water was filtered drinking water from Walmart, and the pyrex was only cleaned with tap-water (rather "hard" water) and soap.
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microwwaves (Score:5, Informative)
same thing happens in a microwave to h20, or any other free floating polar molecule. h20 just happen to absorb the microwave em very efficiently.
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Re:Very, very hot water? (Score:5, Funny)
p.s. Don't drink your tap water! Check the news, it's been contaminated with dihydrogen monoxide, which at sufficiently large quantities can prevent breathing!
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Re:Very, very hot water? (Score:5, Insightful)
Whenever you convert energy from one form to another, you will always end up with less useful energy than you started with. Otherwise, you'd have a perpetual motion machine.
However, there are also considerable losses in transmitting electricity over the grid. There is the ability of hydrogen-powered fuel-cell cars to act as peak-power generators and remove the need for expensive extra generation capacity; given all that it might work out more economically efficient than the current grid if the losses from hydrogen production are not too large.
You're also missing another factor. Our current distributable, mobile, and convenient energy sources (crude oil derivatives) are an environmental disaster, have to be imported from nasty, unstable parts of the world, and are running out. So even if it's not super-efficient, if we can make hydrogen from non-fossil-fuel using energy sources with reasonable efficiency it might be a feasible alternative just as a mobile energy source.
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If they can scale it down, this tech could be... (Score:5, Funny)
Smartass (Score:5, Funny)
I wish I could start a nation at sea (Score:4, Interesting)
I think the reality is that there are so many unecissary regulations in the states, that nuclear power is impossible - and likely will be for a long time. I myself wish I had enough money to buy a ship and put a nuclear reactor on it out in international waters and sell safe and simple hydrogen back to the mainland. It would also be a cool way to reach the next generation of liberty - I mean we haven't really seen any new methods implemented to improve individual freedom and liberty (especially economic) in government in nearly 200 years. I wish I could start a nation at sea.
I want my Mr. Fusion! (Score:5, Funny)
Re:I want my Mr. Fusion! (Score:4, Interesting)
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Re:I want my Mr. Fusion! (Score:5, Funny)
You mean like a Hummer?
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Public-private research team? (Score:5, Funny)
That has already been done (Score:4, Informative)
Here's the reaction [64.233.167.104]
So obvious. (Score:5, Insightful)
I thought of this when someone first told me about fuel cells. To anyone familiar with conventional thermal cycles and the basics of thermodynamics, the approach is obvious. Thermal cycles take advantage of thermal energy gradients. That such a potential could be exploited with fuel cells seems to be an obvious extention. Hot water is easier to separate than cold water, duh! So you heat the water up, separate it and then combine it in a cold fuel cell. The difference is energy you can use but the devil is in the details. It seems easier than using a turbine but you'd want one of those too if you can't extract all of the heat in electrolysis.
I'm glad someone is finally working on it. People are so slow. I expect the petroleum and coal industries to step in and kill it before anyone can use it.
Newer nuclear reactors can produce hydrogen (Score:5, Informative)
Generation IV Nuclear Reactors [uic.com.au]
Very high-temperature gas reactors. These are graphite-moderated, helium-cooled reactors, based on substantial experience . The core can be built of prismatic blocks such as the Japanese HTTR and the GTMHR under development by General Atomics and others in Russia, or it may be pebble bed such as the Chinese HTR-10 and the PBMR under development in South Africa, with international partners. Outlet temperature of 1000C enables thermochemical hydrogen production via an intermediate heat exchanger, with electricity cogeneration, or direct high-efficiency driving of a gas turbine (Brayton cycle). There is some flexibility in fuels, but no recycle. Modules of 600 MW thermal are envisaged
Reactor designs. (Score:5, Informative)
This isn't really correct - although pretty much all the power reactors in the USA are water cooled (primarily due to the Navy's interest is nuclear propulsion), there are plenty of gas cooled reactors elsewhere. Most of our (Britain's) nuclear generating capacity is from either AGR (Advanced Gas-cooled Reactors) or Magnox (named after the Mg-alloy fuel can) reactors, both of which use carbon dioxide as the coolant.
So, the technology may be new to the USA, but there's are wealth of knowledge on designing and running these reactors elsewhere in the world.
Oh yes, they're arguably quite a bit safer than PWRs as well!
Suspicious numbers (Score:4, Informative)
I wonder if they're just making up numbers, as 100% efficiency seems unreasonable good.
Re:Hydrogen grid? (Score:5, Insightful)
You can build the plant in the boonies, but you still need to operate in a region where you can attract enough workers to staff the plant.
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Re:Hydrogen grid? (Score:5, Insightful)
You'd have to build something on the same scale as the current oil pipeline system, but with the added hurdle of being able to hold hydrogen.
The current system won't work since it can't hold hydrogen.
Also with no immediate profit, people tend not to like investing is something they won't see return on in the short term.
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Re:Hydrogen grid? (Score:5, Interesting)
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Re:Hydrogen grid? (Score:5, Informative)
There were interstate oil pipelines completed or under construction before World War II. U-Boat attacks on coastal tankers accelerated the process. Today, there are 200,000 miles of oil pipelines and 2/3 of US oil is transported by pipeline. Houston to New York, the cost is about $1 a barrel, or 2 1/2 cents a gallon at retail. Association of Oil Pipelines [aopl.org]
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Re:Balance the equation (Score:5, Insightful)
You know, I've never seen a post answered by its own sig before ...
No one person shoulders the cost of "total destruction of our environment", it is spread out among everyone. Yet, in your scenario, one person (or corporation or government) shoulders the entire cost, and thus risk. There will be many large corporations looking for this to fail, so you've got your work cut out for you. Until you can find a rich saviour, this won't ever get off the ground.
All we can do is point out the reasons why consumers want this, and the reward/risk ratio will change as consumers will demand it. The risk goes down (the competing energy sources won't be able to cause failure at this point), the reward goes up (there are consumers just waiting to empty their pockets into this rather than traditional fuels), and there will be competitors looking to get their own pieces of this pie.
This, by the way, is exactly how the capitalist "invisible hand" is supposed to work: consumers demand something, whether for purely selfish reasons (materialist), or for purely environmental reasons (it's a cause they're willing to pay for), or for any other reason. Point is, consumers demand what they want, and someone will eventually come along to give it to them. Thus, the key is to drive demand, in order to drive supply.
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Re:Hydrogen grid? (Score:4, Interesting)
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Re:Hydrogen grid? (Score:5, Informative)
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Re:Hydrogen grid? (Score:5, Informative)
Since the location of plants is defined by water, it tends to put them in the same regions where cities grew up, next to lakes and rivers. They try to put them in isolated spots, but by the nature of things, areas around them grow up.
You can't put them in the middle of nebraska cause they don't have a place to get anough water for cooling. Also you want your powersource near the place of use to eliminate losses.
Besides, their is nothing wrong with nuke plants in ones back yard, i would be perfectly happy with such a thing. Far better then any coal plant or similar. It's nuclear, their is nothing to fear, unless you are one with that bizare fear that something that is glassified then incased in indestructable storage containers that are then moved to remote areas has even a remote chance of ever harming you.
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Hot? (Score:4, Funny)
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Re:Heat pollution (Score:5, Informative)
Mini nuclear reactor could power apartment blocks [newscientist.com]
A nuclear reactor designed to generate power in the basement of an apartment block is being developed in Japan
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Re:The oil men (read Bush) (Score:5, Insightful)
They're not oil companies! They're energy companies.
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Re:The oil men (read Bush) (Score:4, Insightful)
The power people OWN the oil. If there was anything that started to interfere with that mechanism, then you will see Government refusal to grant licences to build facilities etc to produce an alternate energy supply. Mark my words.
Think of the oil people as a big version of MS.
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Re:The oil men (read Bush) (Score:4, Insightful)
Theres only two compelling reasons to abandon the current energy paradigm. 1) A new energy source. It has to be so much better than the last one that the profits will outweigh the investment within 5 years. 2) The old energy runs out.
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Nuclear + hydrogen = much higher throughput (Score:5, Interesting)
Fusion of helium-3 would be divine. Pity there isn't much here on Earth. (The moon is another matter.) It also usually costs hundred of dollars per litre. Bear in mind that there are several other reaction paths to fusion that don't require He-3. They aren't as ideal - just more practical.
Solar panels have their place, but they're never going to produce the amount of hydrogen needed for even a single nation's infrastructure. Even if solar panels were much more efficient, electrolysis itself isn't very energy efficient.
(As an aside, I was pleasantly suprised to run across an article about using good old Stirling engines & an array of mirrors to generate power from the sun - at higer efficiencies than panels and at costs comparable to fossil fuels. Have a read [eet.com])
Now, on to the point of the story. Basically, some of the Generation IV nuclear reactor designs* can be used to produce lots of hydrogen, more or less as a byproduct of their operation. (Because of the extreme temperatures) So the fact that you've suddenly got the means for a hydrogen economy is a side-benefit.
Gen. IV reactor designs are cleaner, safer, more efficient, and generally smaller than their clunky old (current) counterparts. Yes, they are still fission. And while MOX reactors (which compose some of the designs) have questions about fuel reuse, a bona fide fusion reactor can be used to re-enrich spent fission fuel. (ie, blanket of uranium around reaction chamber, etc.) Fusion lets you make fission clean, or as close to it as possible.
Why is that important? Because no one is going to initially drop the trillion or so dollars to build the first commercially viable fusion reactor, when and if one is ever designed. ITER [iter.org] itself will be just a stepping stone, if it ever actually gets built. In the mean time, we'll still be fissioning away...
*Because of irrational fear and paranoia in the USA, most commercial reactors are Generation I or II. Not much has changed since the 70s. Nuclear can be dangerous, but it generally isn't and needn't be. It's debatable whether government run power plants would be any better, but it scares the hell out of me that our reactors in the USA are run as cheaply as they can possibly get away with. Capitalism is great, but you just can't try to undercut safety.
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Re:Hydrogen bombs (Score:4, Informative)
BTW most of the people who died on the Hindenburg were burned by DIESEL FUEL, not hydrogen! (or they were killed by the sudden stop at then end of a fall).
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Re:no CO2, but U and Pu (Score:4, Insightful)
Ignore, for a moment, advanced passive power generation and fusion power. What do we have now to power our civilization? Fossil fuels and nuclear energy. If we could reduce our power consumption, or rely more on existing passive generators (like solar and hydro), then we would need less actively generated power. We could never reduce our power requirements to zero without our civilization collapsing (see Dyson's theories, as well as conservation of energy and thermodynamics). This means that we're still stuck with waste products, nuclear or otherwise.
Given only those two choices, I choose nuclear. I recognize the risks and long term hazards of it, but it is still a better alternative to climate change and air pollution. Moreover, in the long term, fossil fuels will run out far sooner than fissile fuel. My hope is that we get working fusion power, and alternative energy sources, but in the meantime nuke plants are the better route.
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Re:no CO2, but U and Pu (Score:4, Interesting)
At the levels of CO2 that we're putting into the atmosphere today, it's likely that biological sinks could reduce CO2 to preindustrial levels in about 200 years, but if we continue to burn fossil fuels for the next two centuries, the biological and short-term chemical sinks will have been saturated.
Based on what we know about the slow (geological) sinks, it could well take on the order of a few million years to get back to preindustrial levels of CO2 from the levels we expect if we burn up all the known coal reserves (estimated at around 250 years from now at current rates of consumption).
Therefore, I am much more concerned with CO2 emissions than with nuclear waste.
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Re:Water vapor is a greenhouse gas too (Score:4, Interesting)
We actually wouldn't have a problem with carbon dioxide emissions if they were a part of the carbon cycle. Biodiesle would not contribute to the greenhouse effect, since the amount of CO2 released and the amount absorbed by the plants producing the fuel would be in equilibrium. However by burning trapped fossil material, which has been out of the carbon cycle and buried for millions of years, we are altering the environment.
Carbon dioxide is normal in the air; animals emit it, plants consume it. Add more total carbon to the system, by depleting an ancient carbon sink, and the net level of CO2 in the air rises. Since the hydrogen you get from electrolysis comes from water, you aren't adding to the net levels of water vapour. For every ounce of water you're releasing into the hydrological cylce, you're taking an ounce out at the other end to get the hydrogen in the first place. No disruption in the hydrological cycle, no warming.
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Yes, it's tied to the hot water systems (Score:5, Insightful)
This system works on the heat production to heat the water. So hydro or wind wouldn't work efficiently. Other systems that use the steam cycle to power turbines probably would.
Using a hydrocarbon based power plant would be defeating the purpose, besides, there's more efficient methods of making hydrogen from hydrocarbonds than even hot water electrolysis.
The mirror type solar power plant might work too, but they cost an order of magnitude more to make per megawatt than a nuclear plant. And they're not manintenance free once built.
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Re:Only Nine Plants Needed... (Score:4, Informative)
Only 900 plants needed!
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Re:still dirty (Score:5, Insightful)
So isn't the stuff that comes out of a coal plant's stacks. Except the nuclear stuff is safely in a pool, rather than in the air that I'm breathing.
but a geopolitical crisis
Just because it's a political "crisis" doesn't mean that it's ultimatly a geological crisis. There are ways to handle the waste.
And factoring in the energy to build these reactors reduces their efficiency
The build energy argument can be used for every technology. Heck, Solar and Wind both have much higher build costs per megawatt.
How about biomass reactors that generate hydrogen from agricultural waste, which are neither radioactive nor wasteful?
Research is progressing on this option too. May the best technology win. Changing economics as well as scientific developments will favor one or the other depending on the situation. People in my area often have multiple fuel heating systems. We'll heat with everything. Wood, Oil, Corn, Electric, and Natural Gas. Price of electricity goes up? Switch to Gas. Gas/Oil goes up? Use electric. Are you really cheap? Chop down some trees. Or buy some dry feed corn and burn that.
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Re:Am I the only one worried? (Score:5, Informative)
Hmm... an incident (TMI) that happened over a quarter century ago? Another that happened 67 years ago? We've come a long way since these incidents. That's what progress is all about; living and learnign and USING this new knowledge for a better system.
And how is the hydrogen fuel to be transported?
With the use of the Texaco Ovonic Hydrogen Systems metal hydride containment units. It creates a stable form of hydrogen. The US DoT has already approved the system.
I'm afraid we'd be inviting disaster and a sitting target for terrorists.
These same circumstances exist today. We're not creating a new hazard.
(nucular for Dubya types)
This is a fairly wise remark from someone who seems to have posted before they sat and really given any thought on the subject. This is what's called a knee jerk reaction.
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Re:um... (Score:4, Insightful)
Which is solid, containable, and produced at centralized facilities which can be scrutinized easily, instead of being pumped out the back of millions of individual cars straight into the atmosphere every day.
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Re:Not enough hydrogen created (Score:4, Insightful)
There's an estimated 360 million gallons of gasoline consumed daily in the US. This plant will produce 400,000 kilos. This may not be enough for a truly large city but it's more than you think it is. It's certainly more than two gas stations worth. To put it into a bit more of a prospective; a gas tanker (semi truck type) holds 9,000 gallons of gas.
We're gonna need a bigger source than that if we want to use hydrogen.
Sure, it's not a singular solution but fuel creation today isn't a singular solution either. It's actually encouraging that we're going to have so many potential sources. If we weren't so reliant on our current sources of oil we'd probably not be in the situation we're in today. Also consider that in all reality fuel cell is a long way off. Is it still going to take a kilo of hydrogen to produce the same energy as a gallon of gas? doubtful. And this plant, if it takes off, will be modified and output will likely be increased.
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Re:Lots of upside, but there is a potential downsi (Score:5, Funny)
It is far worse than one would imagine. You can read more about the dangers here [dhmo.org] about the byproduct of hydrogen combustion. Truly sobering....were they to put these in automobiles, they would generate a key component of acid rain.
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Re:Reality Check pls. (Score:5, Funny)
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