IRA FLATOW, host:
You're listening to TALK OF THE NATION: SCIENCE FRIDAY. I'm Ira Flatow.
A brief program note coming up on Monday - Neal Conan will be here for the discussion on where we should draw the line between political activism and domestic terrorism. Several members of a radical environmental group face sentencing as terrorists. Their supporters argue nobody got hurt; the government disagrees.
Terrorism defined - that's Monday on TALK OF THE NATION. This hour, we're going to be turning to a different approach to reducing carbon emissions: going to a hydrogen economy. And when hydrogen is used and fuel cells are burned in a car, no greenhouse gases are emitted.
But one of the stumbling blocks for using them in cars is the problem of getting the hydrogen to your filling stations. storing it there, then pumping it to your car. We don't have an infrastructure to do that, and people are not keen to the idea of driving around with a big tank of compressed hydrogen despite gasoline being much more dangerous and explosive, but that's another story. Well, hat if you could fill your car instead with a tank of water and make the hydrogen from the water right there in the car when you need it?
Scientists at Purdue University say they have come up with a method to do that: metal pellets, which when dropped into water, release hydrogen. Joining me now is Jerry Woodall. He's a distinguished professor of electrical and computer engineering and director of the Burton D. Morgan Center for entrepreneurship at Purdue University in West Lafayette, Indiana. He joins us from the studios of WBAA. Welcome to the program.
Professor JERRY WOODALL (Electrical and Computer Engineering; Director, Burton D. Morgan Center for Entrepreneurship, Purdue University): I'm glad to be here.
FLATOW: Thank you. Is it as simple as what I described?
Dr. WOODALL: Just about that.
FLATOW: How do you get that to work? It seems like alchemy.
Dr. WOODALL: Well, it's actually very simple high school chemistry. You know that we can use aluminum for lots of things. We can put it in the water and make boats out of it and cook with it. The reason you can do that is aluminum, in its natural state, has a thin native oxide on it that will prevent the water from getting to the core of it, and so the aluminum stays stable. So the oxide is the key to passiving(ph) aluminum.
If that oxide were not there, it would split water readily, and - though what I've done is just merely added another element - in this case, gallium - on the group III part of the periodic table. And when you put that together with aluminum, it - the gallium acts as to prevent the oxide from forming or passiving on the surface so water will freely react to it - with it.
The gallium itself is inert. The gallium itself cannot split water, although it can oxidize in air, so it's a good combination. So we can recover the gallium easily. The aluminum oxide, which is a product, can be easily recycled back to aluminum via commercial processes that are out there. We use them all the time to make new supplies of aluminum from bauxite. So, as far as I can tell, there are no showstoppers for this puppy.
(Soundbite of laughter)
FLATOW: So, you know, I'm going to give you the question that I've been asked many times before - they ask a scientist when they say that - is if you're so smart, why ain't you rich?
Dr. WOODALL: Ah.
(Soundbite of laughter)
Dr. WOODALL: Now that is a good question. You just wait…
FLATOW: Well, there's got to be a - well, describe. There's got to be a showstopper.
Dr. WOODALL: Give me time. I'm only 68 years old, so I've got another 40 years to go.
FLATOW: And you have a great track record. You've invented so many devices. You're not just a hydrogen guy; you invented the semi-conductor lasers that are in our CD players. You've invented transistors, components in solar cells. So people listen when you talk about something new, and I'm certainly interested to find out why. You know, you're at Purdue, this is something new - why hasn't anybody thought about this? And there's going to be a downside to it, or else somebody would have done it, right?
Dr. WOODALL: You're right. You and I believe the same thing. There is nothing new under the sun. So let me tell you why this happened. When you think about it, people have thought about aluminum being a very energetic material in the past. So you can make aluminum powder. You can add a concentrated sodium hydroxide. There are all the kind of things you can do to make aluminum generate hydrogen; it's just they were not thought to be commercially or practically viable.
This came about - in the discovery of my IBM lab back in 1967 when I was working on one of these compound semi-conductor projects that you were talking about. And I discovered that if I have a little liquid of gallium and aluminum together and add water to it, boom - I got hydrogen heat and aluminum oxide forming.
It scared the hell out of me, so I went back to my office and spent a couple of hours, figuring out. And I finally figured, ah, yes, the aluminum atoms at the surface of the liquid metal see - oxygen, I'm sorry, water - they strip the -they pull the water apart and formed aluminum oxides. So in retrospect, it became very obvious that this would happen.
But you ask yourself the question: who in their right mind are going to go around playing around with gallium or aluminum solutions when it's known that if I put gallium and aluminum, it makes the mechanical properties weak, and the main use for your aluminum at the time was its mechanic properties and not the chemical properties.
FLATOW: So how far are we from making this practical?
Dr. WOODALL: It depends on what you mean by practical. I think there are niche markets open to use to use it in a small scale. As you pointed out, the infrastructure is the big issue. I don't think there's any technical barriers. What has to happen is that both politics and the marketplace have to play a role here to move this thing along.
I mean, there are no aluminum filling stations, just like there are only a very few - practically zero number of hydrogen filling stations. They're there to show people that you can actually use hydrogen. BMW, of course, has liquid hydrogen in their tanks to run that really fancy 750-H, I guess, they call it around Munich. And that's exciting, although I don't - I'm not wild about liquid nitrogen in the back of my car, just as - so I wouldn't want compressed hydrogen in the back of a car.
So the thing is, this thing could - is going to be available, to answer your question specifically, in small applications. Like, we're considering making stand-by power units for medically fragile patients in the state of Indiana right now, and our business model is like that of Wal-Mart - you start a little store in Arkansas, you let it grow, and before Sears and Robuck(ph) and Penny can do anything about it, you have Wal-Mart's national - the biggest company in the world, practically.
FLATOW: So see…
Dr. WOODALL: Now I don't think we'll get there with this that way, but it's a start.
FLATOW: But you can actually say, just add water…
Dr. WOODALL: Right.
FLATOW: …and you've got what you…
Dr. WOODALL: Just add water.
FLATOW: …just add water, and out comes the hydrogen.
Dr. WOODALL: Tap water, to boot. It doesn't have to be very pure aluminum, it doesn't have to be pure gallium. So you get rid of the cost issues that way.
FLATOW: Now what about recycling the product that you have left over once you've used up all of the hydrogen that's coming out? Do you have stuff to get rid of?
Dr. WOODALL: Okay, so at the end of the day, at the process, you have hydrogen that you used, you have aluminum oxide - Al2O3, it is chemically. That you send back to the recycling plant, and they pass electric current through this, and it takes it back to the elemental form of aluminum. That process is currently - has an efficiency of 50 percent, which is pretty good. The Alcola folks think it will get to 75 percent in a few number of years. And so then I have to recover the gallium, but remember the gallium is a liquid, it's inert, and it doesn't get involved in the reaction, except there's a sort of like a catalyst to prevent the aluminum oxide from passiving the fuel.
FLATOW: Ah, but aye, there's the rub. If you have to use electricity to recover it, don't you now again have to generate electricity in the process?
Dr. WOODALL: Well, people tell me - yeah, but how do I regenerate dinosaurs? I don't know of a dinosaur form around right now…
(Soundbite of laughter)
Dr. WOODALL: So you tell me. I mean, look…
Dr. WOODALL: We can't violate - the laws of thermodynamics.
Dr. WOODALL: So you have to put more energy back than you get out. But so what? I'll use solar farms in the long haul. I can use wind turbines. And even - so economically speaking, if I use - if I co-locate aluminum recycling plant next to a nuclear power plant, I can recycle the aluminum oxide back to aluminum for two cents a kilowatt hour. And those are published numbers, so that makes the cost equivalent for the same amount of energy of aluminum about the same as gasoline.
FLATOW: So you could do the same thing with a wind power plant - you could just bring the aluminum…
Dr. WOODALL: Absolutely.
FLATOW: …to there, or so…
Dr. WOODALL: Throw the dice, let her rip.
(Soundbite of laughter)
FLATOW: You know, it sounds - we just did another segment with another scientist - maybe you were listening - who had his own idea…
Dr. WOODALL: I was, though, but (unintelligible).
FLATOW: You know, these things sound so good. They sound, you know, have you broached the government with this idea and maybe get some research funding for it, or do you not need it anymore? Why not private industry, go to Alcola or somebody like that?
Dr. WOODALL: So that's really a good question. The answer is, I've done that. With all modesty, when you make a revolutionary breakthrough, it takes some time for the people around you are interested in this thing to accept it. So at this point in time, my colleagues at DOE are still pondering this thing over. I hope to be able to get some funding from them someday. But I also - one of - at my age, I would like to commercialize this thing, get it out there. I mean, it's not about money. I think it's that my grandchildren are actually going to be driving cars with this stuff in it.
Dr. WOODALL: I predict that.
FLATOW: So why not get the car companies involved in investing in this?
Dr. WOODALL: Well, we will at some point in time. Remember, my role is to develop the fuel, so we have - there's a whole bunch of systems issues that need to be engineered that I need to put team - teams together to do this. But this stage of the project, I found something that's reproducible. It's real. You could come visit me in my laboratory, if you like, sometime. I'll give you a demo. I mean, it's not something you have to wait three or four days when the wind is right for it to work. It actually works every time.
FLATOW: Let's go to the phones. Chris in San Francisco. Hi. Welcome to SCIENCE FRIDAY.
CHRIS (Caller): Yes, hi. Thank you. I just - I applaud the science and the progress that's going on here with technology, but I think this discussion needs to address limits in that we need to be limiting our emissions. Fundamentally, we need to stop developing technological excuses for so much auto and jet and other kinds of use that pollutes the environment so profoundly.
And I guess what I want to contribute to this is that, you know, we need to remember that more cars on the road means more production of cars, which means more mining, which means more energy consumption and fossil fuel use for all the machines that are required to mine the metals and produce the rubber tires and all the things that go into - whether it's jets, cars, ships. You know, I'm not saying we're going to get rid of these things, obviously, but I think that, you know, the political solutions are critical in this, and we need to be talking about, you know, not just having some nice technological fixes. You know, and again, I applaud the science on this thing…
FLATOW: Let me get a…
CHRIS: By really trying to get the consumption of these fossil fuels and all the machinery that goes into that.
Dr. WOODALL: Yeah. Well, if this works out, there's plenty of aluminum on the planet. There's plenty of water. I mean, three-quarters of the planet is water, so this will work with salt water. So our missions are just water vapor out of the exhaust pipe. In fact, I have a picture of me over at the (unintelligible) labs with my nose on the exhaust pipe of an internal combustion engine. I'm still alive. So I claim that if we move to an aluminum economy and we use solar and other forms that don't heat up the planet, I'm not so much worried about green house; I'm more worried about the planet getting too hot. And so that's a longer haul thing, but we have to worry about it. So if we do all - if we make everything with hydrogen fuel, we don't add any more greenhouse gases to the planet, and we don't add extra heat to the planet.
FLATOW: Talking with Jerry Woodall this hour on TALK OF THE NATION: SCIENCE FRIDAY from NPR News. I'm Ira Flatow.
So Jerry, you're basically saying if we move to a hydrogen-aluminum economy, we can make the hydrogen we need to from water. We can then recycle the aluminum and use solar or wind energy as the electrical source so we don't have to worry about pollution stemming from new production of hydrogen using fossil fuels.
Dr. WOODALL: Right.
FLATOW: And we can make enough of this to have a real impact.
Dr. WOODALL: I think so.
FLATOW: You think so. You know, things move slowly in this country or other countries. You know, in Europe, they think a lot greener than they do over here. Any interest over the air in…
Dr. WOODALL: Well, I've - I have - I was in Singapore when the press release was released, and sort of seeing that it's not a big country, but I spent my evenings answering emails. I've got about 150 of these things from all over the world. I was really shocked about that. So this thing is getting pretty good coverage, so we'll see what happens as a result of this.
FLATOW: Do you have a team working on this? Are you assembling…
Dr. WOODALL: I have two students, a research scientist. I have a CEO that shows up at our meetings every week, and I have a few other consultants - informal consultants - at Purdue that work with me on this. So we're kind of a, you know, building this up from scratch, and hopefully more people will get interested in working with me on this.
FLATOW: Let's see if I can get another call in - from David in San Jose. Hi, David. Quickly.
DAVID (Caller): Hi. Yeah. I guess I'm just wondering how efficient is this process? How much hydrogen do you produce, and how much aluminum do you use? Is it like, (unintelligible) exact, like you have to use quite a bit of aluminum to make the hydrogen?
And also, the second question back to what Ira said about, you know, it takes energy to make the aluminum. So how much does it actually take to make the aluminum originally versus also recycling it? So is there a net? You can't buy (unintelligible) access(ph). I mean, how efficient is the process in terms of energy use overall?
Dr. WOODALL: Okay, I can answer that question. It turns out that two atoms of aluminum make three atoms of hydrogen gas - hundred percent efficient that way. So the only expenditure of energy is to bring the aluminum oxide back to aluminum. As I said earlier, that process is currently 50 percent. So when you consider fossil fuels and solar efficiencies of growing plants, which is about 10 to the minus four, I think 50 percent is a lot better than 10 to the minus four than growing plants. Of course, we have lots of land area - I won't argue that point - but still, this is one of the more efficient ways of making hydrogen, because the return process back to the aluminum is very efficient.
FLATOW: Do we have to mine a lot more aluminum if we go to an aluminum economy? And is that going to add to the energy burden?
Dr. WOODALL: Okay, that is a really good question. It turns out that the world has about a factor of two surplus capacity now. In other words, by the time they're finished making your Coke cans and other things you want to make with aluminum, now there's about 50 percent over capacity there. And if we were to use that, we could drive about - we could run about half the cars in the U.S. on that. So if you go worldwide, you want to get rid of all fossil fuels for energy - mobile energy applications, so yeah, we'll have to mine more, but there's plenty there to mine.
FLATOW: And it won't upset the environment with all of the…
Dr. WOODALL: No.
FLATOW: …energy it takes to mine it?
Dr. WOODALL: No.
FLATOW: No? All right, Jerry. Good luck. Thank you, Dr. Woodall, for taking your time to talk with us.
Dr. WOODALL: Well, thanks for having me on the show.
FLATOW: And we're always looking for new ideas and giving - you know, shining some light in those dark areas that never get any light for inventors and entrepreneurs like you. Thank you for taking time to be with us.
Dr. WOODALL: Thank you.
FLATOW: Jerry Woodall is distinguished professor of electrical and computer engineering and director of the Burton D. Morgan Center for Entrepreneurship at Purdue University in West Lafayette, Indian.
I'm Ira Flatow in New York.
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