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Creating Hydrogen With (Very) Hot Water
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."
no, PVT diagram shows that you have very hot water without steam at high pressures.
A pot of boiling water on your stove will probably not reach a higher temperature. This is because of the surrounding air pressure. If they put this in a closed system like a "pressure cooker", it could get hotter.
That's why a pressure cooker works faster than an open pot. The increased pressure allows the water to boil at a higher temperature.
Is it just me or water can't be very very hot? At about 100 degrees Celcius, it vaporize...
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.
It depends on the pressure the water is kept under...that's the reason that you're able to prepare food faster in a Pressure Cooker.
Water can be superheated as much as you please, it simply has to be at a high enough pressure. Past water's critical point (about 650 K and 22 MPa), it becomes a supercritical vapor, indistinguishable from liquid or vapor. Additionally, the boundary between liquid and gas dissapears, and the properties of the substance are somewhat different.
Article Link, Sans first born
Already invented:
Mini nuclear reactor could power apartment blocks
A nuclear reactor designed to generate power in the basement of an apartment block is being developed in Japan
It has been known for some time that blowing hot steam across coke results in hydrogen, which is how most commercial hydrogen is made.
Here's the reaction
Because when its hot, it uses less energy to do the electrolysis. RTFA. Currently it takes 3-4 times the energy to do the electrolysis than you get out by putting the hydrogen and oxygen back together.
> In fact how is this make more pure hydrogen? there isnt another gas in distilled water and when the gasses seperate, they did not come in contact with any outside objects.
The goal isn't to make purer hydrogen, it's to produce hydrogen using less energy.
http://jlnlabs.online.fr/cfr/index.htm
If you were being serious about that statement your stupidity is showing. Hydrogen is less explosive than gasoline, and unless you can heat it to a temperature of a few million degrees or so you won't see hydrogen exploding like at bikini atol.
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).
Generation IV Nuclear Reactors
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
The fellas at Ballard Power Systems seem to have an interesting vision in this regard. (I'm trying to recall what I heard on a CBC interview with one of the company's founders, so what I describe here may be partly my own fabrication). Anyway, they describe an electrical grid in which individual cars help generate and store electricity for the entire system. Something about micro power plants. You may choose to sell your power to the grid (when your car is unused), benefitting from the current market price of the power. Similarly, you can purchase electricity and store it in your car (in hydrogen form) hopefully taking advantage of a cheap power rate. Buy low, sell high. Anyway it all seems very interesting to me, an idea of millions of micro power plants contributing to the greater power grid. One big distributed storage and generation system, probably better at absorbing peak power demands too -- you see that it's 1 pm on a hot summer day and the grid will pay big $$ for your power, you take advantage of that.
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!
I assume you also have touched a cup of microwaved H2o and had it instantly boil over on your hand.
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.
If you don't understand any of my sayings, come to me in private and I shall take you in my German mouth.
What would be far more influential in building the hydrogen economy is solar powered electralysis made cheap. I've heard about some prototypes, but I think they're currently far more than your average gas station can afford. Local production would have to be the intermediate solution that bridges between a concept and widespread adoption.
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Open Source Sysadmin
the waste produced is no more dangerous than the junk that a coal plant makes. all that is different is that it is more confined and does not affect the health of the population.... but why should we care about that?
also, you do know that the longer the waste takes to degrade, the less harmful it is, don't you?
also, if we reprocessed our waste, we could reuse it., I mean, we WANT controllable radioactive materials and reprocessing helps turn the waste into a controllable substance.
I am the Alpha and the Omega-3
Only 900 plants needed!
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
Thats at standard pressure. The boiling point of water is entirely dependant on the ambient pressure. Some recipies even need to be modified for use at high altitudes because the water will boil at a tempurature significantly less than 100. Nuclear reactors have coolant water at about 700 degrees F, which is fine until the pipe cracks and boils the three guys in the room at the time.(This really happend and is the only known deaths directly reated to nuclear energy production in this country! What a way to go though. Wonder how fast it was?)
Smoking is an expensive, slow, and unreliable method of suicide.
Nuclear companies have nuclear power reactors to put out hydrogen (as a byproduct) ready and good to go, and have had them ready for quite some time. The hold up, in America, is that people are afraid of Nuclear Power, but in a few years as coal rises in cost (it will this winter for example--the cost of the coal has tripled on the East Coast of the U.S., but not the West Coast), there will be a demand for new reactors. However, the reactors that are desired are high energy steam generators, which are NOT the hydrogen power byproduct generators.
The reason being is because they are still fine tuning these hydrogen byproduct generators to not waste so much energy actually creating the hydrogen (costs energy to split from the other molecules, such as H2O), which is a big concern for the power companies, as they want to maximize profit and that means not wasting energy. Sure, you have the hydrogen eventually, but a lot of the energy is just lost in the conversion process.
Hydrogen has about 120MJ/kg of energy (lower heat value). They're saying that it either makes 300 MW of electricity or 2.5 kg/sec of hydrogen, which would imply 100% efficiency for electricty->hydrogen (2.5 kg/sec is the same as 300MW).
I wonder if they're just making up numbers, as 100% efficiency seems unreasonable good.
Nuclear plants are built in places where the conditions are right. Primarily where there is a large source of water for cooling. Usualy big lakes or rivers, sometimes oceans. You need a massive amount of water to keap them going without killing all the fish and such in the water source when the hot water is dumped back in.
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.
Read the article on geothermal power. Once the water has been heated, it will return as high-pressure steam. In California, the temperature difference can be as much as 3632F per mile drilled downwards.
Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads
Has everyone forgotten the Three Mile Island and Hindenburg accidents?
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.
Dedicated Cthulhu Cultist since 4523 BC.
WASHINGTON, Nov. 27 - Researchers at a government nuclear laboratory and a ceramics company in Salt Lake City say they have found a way to produce pure hydrogen with far less energy than other methods, raising the possibility of using nuclear power to indirectly wean the transportation system from its dependence on oil.
The development would move the country closer to the Energy Department's goal of a "hydrogen economy," in which hydrogen would be created through a variety of means, and would be consumed by devices called fuel cells, to make electricity to run cars and for other purposes. Experts cite three big roadblocks to a hydrogen economy: manufacturing hydrogen cleanly and at low cost, finding a way to ship it and store it on the vehicles that use it, and reducing the astronomical price of fuel cells.
"This is a breakthrough in the first part," said J. Stephen Herring, a consulting engineer at the Idaho National Engineering and Environmental Laboratory, which plans to announce the development on Monday with Cerametec Inc. of Salt Lake City.
The developers also said the hydrogen could be used by oil companies to stretch oil supplies even without solving the fuel cell and transportation problems.
Mr. Herring said the experimental work showed the "highest-known production rate of hydrogen by high-temperature electrolysis."
But the plan requires the building of a new kind of nuclear reactor, at a time when the United States is not even building conventional reactors. And the cost estimates are uncertain.
The heart of the plan is an improvement on the most convenient way to make hydrogen, which is to run electric current through water, splitting the H2O molecule into hydrogen and oxygen. This process, called electrolysis, now has a drawback: if the electricity comes from coal, which is the biggest source of power in this country, then the energy value of the ingredients - the amount of energy given off when the fuel is burned - is three and a half to four times larger than the energy value of the product. Also, carbon dioxide and nitrogen oxide emissions increase when the additional coal is burned.
Hydrogen can also be made by mixing steam with natural gas and breaking apart both molecules, but the price of natural gas is rising rapidly.
The new method involves running electricity through water that has a very high temperature. As the water molecule breaks up, a ceramic sieve separates the oxygen from the hydrogen. The resulting hydrogen has about half the energy value of the energy put into the process, the developers say. Such losses may be acceptable, or even desirable, because hydrogen for a nuclear reactor can be substituted for oil, which is imported and expensive, and because the basic fuel, uranium, is plentiful.
The idea is to build a reactor that would heat the cooling medium in the nuclear core, in this case helium gas, to about 1,000 degrees Celsius, or more than 1,800 degrees Fahrenheit. The existing generation of reactors, used exclusively for electric generation, use water for cooling and heat it to only about 300 degrees Celsius.
The hot gas would be used two ways. It would spin a turbine to make electricity, which could be run through the water being separated. And it would heat that water, to 800 degrees Celsius. But if electricity demand on the power grid ran extremely high, the hydrogen production could easily be shut down for a few hours, and all of the energy could be converted to electricity, designers say.
The goal is to create a reactor that could produce about 300 megawatts of electricity for the grid, enough to run about 300,000 window air-conditioners, or produce about 2.5 kilos of hydrogen per second. When burned, a kilo of hydrogen has about the same energy value as a gallon of unleaded regular gasoline. But fuel cells, which work without burning, get about twice as much work out of each unit of fuel. So if used in automotive fuel cells, the reactor might replace more than 400,000 gallons of gasoline per
We have secretly replaced these Slashdot mods' sense of humor with a rusty nail. Let's see if they notice!!
I don't think it's that hard actually.
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.
Even a tiny nuclear reactor contains more radioactive material than the Hiroshima bomb. Blowing one up with a truckload of conventional explosives may not kill a lot of people, but surely will contaminate a large area for a long time.
One of the "problems" with so called dirty-bombs fashioned from reactor material is that you really can't kill a lot of people. The effect will be mostly psychological.
Thankfully, the material inside anything but a research reactor is very low enrichment. Say 3-10% at most. To make a real Nuke, you need 85-95% enrichment. And a pretty sophisticated bomb design - you can't just pack it with TNT and hope.
So what are we left with?
If you just blow the thing up: really, really deadly stuff (like radioactive Xenon, etc) has a short half-life or otherwise quickly clears out. What you're left to deal with are several chunks of uranium. They're harmful, but only localy. The area can be closed off and decontaminated. Few people will die.
If you want a much bigger disbursion: You have to first grind the nasty stuff down into a fine powder. Very risky to do for a terrorist, even with lots of fancy equipment that likely wouldn't have. When you blow it up, it spreads the dust over a much larger area. The downside is that the dose to any indiviual is going to be much lower. You'll make some people sick, sure, but you won't kill many people.
This is all Good For Us(tm).
A much greater threat is theft of radioisotopes from hospitals, etc, which are relatively unguarded. Nothing like putting "deadly radioisotopes" in a town's water supply to comepletely freak out the general populace.
Which is what they* want.
*insert your favorite evil terrorist group here.
A preposition is a terrible thing to end a sentence with.
1) New reactor designs need far less water, and some of them need no water at all. Two of these designs have been featured here on /. within the last 4 months.
;-)
:-)
2) There is a nuclear reactor located in Ft. Calhoun Nebraska. Suprisingly there are these things called "Rivers" running through there.
3) Much electricity is shipped all over the place,even between countries here on the North American continent, despite "losses" over these other thingies called "high tension lines".
4) Coal sucks.
These "spots" of super heated water occur around what are called black smokers. The magma, or more accurately, mantle, is drawn up at mid ocean ridges 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.
Looks can be deceiving. Or CAN they?
No, you're not the only one who's worried, but you also don't have a clue. TMI was 25 years ago, presumably we've learned a few things about nuclear power since then. Also let's look at what happened at TMI, there was an accident, and the reactor containment worked. End of story.
As for the Hindenburg, puhleeeze, could you pull your frickin head out of your ass for one frickin second here? Firstly do you have any natural gas powered appliances in your house (stove, dryer, gas fireplace, furnace)? If you do then you might be shocked to know that they burn methane gas, which is made largely of gasp hydrogen. Has your house exploded yet? No? OK. Let's also look at the fact that recent analyses (you can find one here) have shown that while the hydrogen in the Hindenburg contributed to the fire the proximate cause was the doping on the dirigible's fabric skin, which was composed of aluminum, iron oxide and cellulose nitrate, all of which are flammable. Hell, NASA has been handling liquid hydrogen for nearly 50 years, how many rockets have they had explode because of an accident with it? Not any that I can think of (the Challenger went down because the Solid Rocket Boosters, which contain aluminum powder similar to that used to coat the skin of the Hindenburg, burned through).
Finally, if you want to see some really nasty and horrific burns just head down to your local hospital burn ward and check out the guys who have burned themselves with gasoline. That's right, gasoline, that stuff you pump into your car every day is really, really, really flammable and nasty and if you get some burning gasoline on your skin you're pretty much guaranteed at least a second degree burn, if not worse. Yet despite this we manage to fuel millions of cars which drive millions of miles every day without having too many flaming wrecks along our roads and highways.
As for the threat from terrorism we've already seen what terrorists can do. Did we stop flying airplanes? No, we just put largely ineffective security measures in place. But if a terrorist ever tries to hijack a plane with a box cutter again he's going to find himself head first up to his shoulders in that blue liquid they put in the airplane toilets while hordes of angry passengers pound that box cutter right up his ass. Terrorism is a risk, but it really pisses me off how many people just throw it up as an excuse not to do something rather than as a risk that needs to be taken into account as part of the overall cost / benefit analysis of a specific action.
cheap labor conservatives - they want to keep you hungry enough to be thankful for minimum wage.
The big problem with geothermal is keeping the hole "clean".The water you dump down comes back full of various minerals which have a tendency to clog the plumbing. Nobody has yet found a good way of dealing with this.
If a job's not worth doing, it's not worth doing right.
polar h20 molecules are flipped or spun as the microwave passes by them. because the em field emparts energy into the molecules, they can contain enough energy to phase shift. Think about covering a gym floor with basket balls so that none are touching. Then somehow make every ball spin at 10000 rpm. At first the balls would continue to sit on the floor spinning really fast. They have a ton of energy, but are still floor balls. Then a single ball is nudged into it's neighbor. Suddenly a chain reaction would happen with basketballs flying everywhere as the spin energy is converted into movement energy.
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.
No, Standard Temperature and Pressure is what he means. When you say STP it refers to the surroundings, not the system.
Additionally, the boundary between liquid and gas dissapears, and the properties of the substance are somewhat different.
The change in properties is what's important to the separation of hydrogen and oxygen. Past the supercritical point, water becomes non-polar and more acidic.
From memory there was some work done a while back on producing peroxides using supercritical water, carbon dioxide and palladium catalysts. Acetylenes were the byproduct, and I wonder now if there might be an energy storage pathway in that reaction.
"I've got more toys than Teruhisa Kitahara."
Sounds like a good idea to me, but one thing to keep in mind is that hydrogen tends to leak out of just about any container you try and keep it in, so over a long distance pipeline you might lose a significant portion of your hydrogen to the atmosphere.
I don't care if it's 90,000 hectares. That lake was not my doing.
It's not a get rick quick scheme for anyone.
The point is that at peak, say a hot 1 PM, your car generates electricity to supply that peak. Subpeak, say midnight, your car draws power to charge its storage cells.
So instead of having the 300 power plants required to meet that peak demand and simply SHUTTING OFF 200 of those plants at night, you build 200 power plants and run them continuously at full power. You use massive numbers of parked cars to supply the peak power and to flatten the load. Building 100 less power plants saves money. Across the entire population the net cost of power is lower.
The reason you buy/sell energy from the cars is that, well, you need to pay to charge the car and you need to offer people money to get them to use their car to power the grid. Overall anyone using their car to power the peak grid will make slightly more money than they pay to charge their cars. So not only will their fuel cost be zero, but that small profit would subsidize the cost of the power-generating cars. People who own generators (cars) would be paid by the people using peak airconditioners. And yes, if you own both the car and the airconditioner you break even - you wind up powering your own air conditioner for free. You save money.
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- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
From the biodiesel page at the University of New Hampshire:
For information on better energy alternatives, check the above URL or the one in my sig.
Tech Public Policy stuff
Try a search on SEGS and Sandia. You don't need sterlings. Sterlings are great and they look cool with sunflower reflectors, but more conventional designs work great right now today here in California. Each of the newer SEGS units is 90MW and they use conventional steam turbines and trough reflectors. Nothing fancy. George Bush Sr. had nothing but praise for them because they were totally for profit and private and on a scale that no backyard solar freak could afford.
The intriguing thing about the SEGS literature, which is abundant, is that you find that they really didn't know what to expect when they started and were typically surprised by the amount of heat they had generated.
Which brings us to this Slashdot topic. SEGS uses elongated troughs, but using hemispheric dishes, or sunflowers as they are known, creates enormous point heat. After all, you're focusing the energy of a vast nuclear fusion reaction. In fact, the heat is often compared to that created in nuclear reactions for the obvious reason that it literally IS the direct result of fusion in the Sun.
So, why not try this same experiment with a, say thirty meter, sunflower?
Solar thermal and geothermal potentially put wind and PV and even hydro to shame and yet the surface has only been scratched because they involve such large scale projects there has to be a critical mass of political will.
It was produced by piping hot steam through a metal can containing red hot coal. The steam that went in one end came out as H2 + CO and CO2
The reaction was: 2H2O + C => CO + H2 + H2O => CO2 + 2H2
But since CO burns as nicely in a stove as H2, the reaction was set up not to go to completion so that a one to one mixture of H2 and CO was produced via H2O + C => CO + H2
This is the origin of the idea of committing suicide by putting your head in the oven ( like the Tom Petty song ). A mixture of CO and H2 was quite deadly and probably painless to breathe.