Purdue University engineers develop cost competitive hydrogen on demand system

[HoosierRon]

As if Indiana isn't doing enough already to replace foreign oil with domestic energy, now we have this story from the Hoosier state.

Purdue Universtiy develops economic hydrogen on demand process

Written by Giles Clark, London
Wednesday, 20 February 2008

Purdue University engineers have developed a new aluminum-rich alloy that produces hydrogen, by splitting water, for transportation and power generation. Moreover, says the team, the process is economically competitive with conventional fuels.

"We now have an economically viable process for producing hydrogen on-demand for vehicles, electrical generating stations and other applications," said Jerry Woodall, a professor of electrical and computer engineering at Purdue who invented the process.
...
When immersed in water, the alloy splits water molecules into hydrogen and oxygen, which immediately reacts with the aluminum to produce aluminum oxide, also called alumina, which can be recycled back into aluminum. Recycling aluminum from nearly pure alumina is less expensive than mining the aluminum-containing ore bauxite, making the technology more competitive with other forms of energy production, Woodall said.

"After recycling both the aluminum oxide back to aluminum and the inert gallium-indium-tin alloy only 60 times, the cost of producing energy both as hydrogen and heat using the technology would be reduced to 10 cents per kilowatt hour, making it competitive with other energy technologies," Woodall said.

If you have a very, very, very deep interest in metallurgy, you can read the rest of the article.

[HotCarNut]

Good article, but it would require a massive change in infrastructure to accomodate the necessary recycling efforts. It would also take a large quantity of aluminum to make it all work. Guess if this comes to fruition, we'll be back to drinking Coke out of glass bottles again....

[Silverado14]

As a 2001 Purdue University Grad, makes me proud to be Boilermaker. Keep in mind, this is just the start, Purdue and other universities are developing many more ways to get us off of OPEC oil! Boiler up!

[MechEng]

Originally Posted by HotCarNut

Good article, but it would require a massive change in infrastructure to accomodate the necessary recycling efforts. It would also take a large quantity of aluminum to make it all work. Guess if this comes to fruition, we'll be back to drinking Coke out of glass bottles again....

This process would take a lot of aluminum but not as much as you think. The aluminum industry is already massive and the amount of aluminum needed would still only be a fraction of this. Considering the process is 100% recyclable. And Bauxite (Aluminum and gallium) is already one of the worlds most abundent resources.

I could see this work. Add pellets of the alloy to your tank. Fill with distilled (or highly purified) water [This I actually see as a bigger challenge]. And it produces hydrogen.

After the aluminum has reacted empty the tank to be sent to a recyler and refill it.

Of coarse you would have to have a system in place to determine fuel range. This too could be trickey.

[rsbaker]

Hybrids are good, biofuels are OK, but I have always felt that Hydrogen would ultimately be the answer to fossil fuels. It requires a rething and reengineering of our entire distribution infrastructure.

Assuming that the "Hydrogen Economy" comes to pass, there will certainly be a need for the typical refueling stations that we have always been accustomed to with Gasoline and Diesel but I don't think we would ultimatly have nearly as many of them. I invision every home having a hydrogen generating appliance in their Garage or back yard that produces Hydrogen 24/7 and and stores it in a tank maybe the size of a washing machine or refrigerator. Everyone with a hydrogen fuel cell car or even internal cumbustion engines converted to burn hydrogen could refill every evening at home. This would be the best way to liberate everyone from oil companies and foreign Oil imports. It's just going to take political will to push this and to educate the american people. I think the auto companies would jump on board with some directed tax incintives and rebates to consumers who invest in a Home Hydrogen generator and hydrogen powered vehicles in the beginning untill it really starts to catch on.

[jlt0x]

Cheap(er) hydrogen...wonderful. Could this new invention be the boost to propell hydrogen (and hydrogen-electric hybrid) engines to the forefront of the next generation of powertrain systems?

[Greg Burr]

[quote=rsbaker;1324364]Hybrids are good, biofuels are OK, but I have always felt that Hydrogen would ultimately be the answer to fossil fuels. It requires a rething and reengineering of our entire distribution infrastructure.

I feel (I don't quite know) that hydrogen and fuel cells is the best answer, but I also like cellulosic ehtanol, too.

Maybe hydogen fuel cells are worthy of a national effort, a Manhattan project.

[brianidaho]

Originally Posted by HoosierRon

As if Indiana isn't doing enough already to replace foreign oil with domestic energy, now we have this story from the Hoosier state.

Purdue Universtiy develops economic hydrogen on demand process



If you have a very, very, very deep interest in metallurgy, you can read the rest of the article.

Interesting, so the aluminum alloy is basically the "storage medium" for electricity, and the water supplies the source for H2. If I understand this correctly, you oxidize the Al alloy into alumina, basically reversing the aluminum production process, it is this released energy that seperates the water generating H2. Then you have to exchange the alumina for fresh Al alloy to refuel as it were.

While interesting, it doesn't strike me as very appealing to the consumer. The seperation of alumina into aluminum is very power and capital intensive, and is the prime cost of aluminum.

In addition, you are going through many conversion processes, electricity to aluminum to hydrogen and back to electricity, to get useful energy, how severe are the losses at the various conversion points?

[GMforME]

I read this article a while back and watched a video on it. Its a great breakthrough but it has a big deawback. When the reaction is done it leaves all the sludge from the reacted alumunium in the tank. So the problem is what to do with it. Its more than a trace amount. When the process is done about 50% of the origional alumunium/gallium volume is left over as black sludge.

[MisterMe]

Originally Posted by brianidaho

...

In addition, you are going through many conversion processes, electricity to aluminum to hydrogen and back to electricity, to get useful energy, how severe are the losses at the various conversion points?

This is an issue that you have with every energy conversion technology. It is called the Second Law of Thermodynamics. Look it up.

If you read the OP, then you should have noticed that this technology is projected to experience a price drop to $0.10/kWh. By comparison, gasoline at its present pump price of about $3.00/gallon is about $0.085/kWh. Where the price of gasoline exceeds $3.50/gallon, hydrogen produced by this technology promises to be cheaper than gasoline.

[brianidaho]

Originally Posted by MisterMe

This is an issue that you have with every energy conversion technology. It is called the Second Law of Thermodynamics. Look it up.

If you read the OP, then you should have noticed that this technology is projected to experience a price drop to $0.10/kWh. I am currently doing calculations to compare this to gasoline. I will report back when I am done.

Though it's been some 20 years since I took thermodynamics, I do recall that the second law of thermodynamics states that the entropy of a system will tend to increase over time. This is often summarised as increasing randomness. I'm not sure how it applies specifically to efficiency losses converting from one "energy medium" (for lack of a better term) to another, it's not just second law considerations, though they are part of the issue.

If you look further into the article you see:

"After recycling both the aluminum oxide back to aluminum and the inert gallium-indium-tin alloy only 60 times, the cost of producing energy both as hydrogen and heat using the technology would be reduced to 10 cents per kilowatt hour, making it competitive with other energy technologies," Woodall said. "

He is discussing both the production of hydrogen and (presumably waste) heat as $.10/kWh, not the end cost of the mechanical energy produced, after 2 more conversions. He also is not discussing the loss of the Al alloy throughout the process, one would have to wonder just how much of the original mixture is left after 60 conversions.

Still, looks like interesting technology, it will be interesting to see where it goes.

One more item, this may make sense for the "on-board" mobile production of H2 from Al, just because of how much easier it is to store solid AL, but it doesn't make sense for stationary applications. Why not just hydrolize H20, forget the whole Al step.

[MisterMe]

As you know, Al oxidizes very rapidly. For fresh Al metal, oxidation is almost instantaneous. The Al strips away the O2 from H2O giving rise to the rapid release of H2. Makes sense to me. I am anxious to read their papers to learn the details.

[D C]

Hydrogen is still a net-negative energy source. You need to make the aluminum from bauxite, you need to make the alloy. You put more energy into it than you get out of it.

[MechEng]

Originally Posted by MisterMe

This is an issue that you have with every energy conversion technology. It is called the Second Law of Thermodynamics. Look it up.

If you read the OP, then you should have noticed that this technology is projected to experience a price drop to $0.10/kWh. By comparison, gasoline at its present pump price of about $3.00/gallon is about $0.085/kWh. Where the price of gasoline exceeds $3.50/gallon, hydrogen produced by this technology promises to be cheaper than gasoline.

There is one big thing you forgot to factor in. You are comparing the processes on an energy to energy basis. But in a fuel cell vehicle more of that energy will reach the wheels than in a gasoline powered vehicle. A fuel cell vehicle is about 3 times more efficent than a gasoline powered vehicle.

So where 1KWh of power from a fuel cell does just as much work as 3KWh from gasoline. So using $0.10/KWh to produce hydrogen (assuming conversion efficency is very high) is far cheaper than using gasoline at $0.085/KWh.

[regfootball]

Originally Posted by D C

Hydrogen is still a net-negative energy source. You need to make the aluminum from bauxite, you need to make the alloy. You put more energy into it than you get out of it.

every energy source requires investment