Name: Fuel Cells
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<div class="rich-text">(This video is no longer available for streaming.) Hydrogen fuel cell cars, whose only tailpipe emission is water, are often hailed as one solution to our energy woes. But many hurdles remain, including lowering the cells' cost, building filling stations, and finding green ways to produce hydrogen. Meantime, our NOVA scienceNOW host test-drives a prototype fuel cell car, with "Car Talk" hosts Tom and Ray Magliozzi along for an amusing ride.
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Hydrogen fuel cell cars promise pollution-free driving, but will we see them anytime soon?

<div class="rich-text">Hydrogen fuel cell cars promise pollution-free driving, but will we see them anytime soon?</div>

Fuel Cells

Tech & Engineering

<div class="rich-text"><h3>
 FUEL CELLS
</h3>

 PBS Airdate: July 26, 2005



 ROBERT KRULWICH:
 
 Hi, I'm Robert Krulwich, and welcome to NOVA
ScienceNOW, where we consider not one, but several science stories. Tonight,
they're basically puzzles beginning with a problem, so just...


 Come on back. Come on back and...all right, stop. Good. The internal
combustion engine, which fouls the air and uses gas which comes from
oil—which is getting expensive, involves the Middle East, gets us into
all kinds of fights—who wouldn't want to replace this with a more
efficient and affordable alternative?


 But is there an alternative?


 Well, there is this engine we keep hearing about which is supposed to be
fabulous. It's coming "soon." But the puzzle is, how soon?


 Every year, Detroit unveils, with much to do, a "Car of the Future." And
the hoopla here isn't about what this car does. It's about what this car
doesn't do. This car doesn't use gasoline, none, because it is powered by a
fuel cell.



 GEORGE W. BUSH
 
 (President of the United States, 2001- )
 
 :
 
 Fuel
cells...



 NEWS ANCHOR :
 
 ...fuel cells.



 NEWS CORRESPONDENT:
 
 ...powered by a fuel cell.



 GEORGE W. BUSH:
 
 Fuel cells are the wave of the future.



 NEWS CORRESPONDENT:
 
 The wave of the future.



 ROBERT KRULWICH:
 
 Really? This is the future? Well maybe we
should take a closer look.


 So I decided to test drive a fuel-cell car, and I invited a couple of
friends to come along.


 What do we think?



 TOM MAGLIOZZI:
 
 We don't know anything.



 ROBERT KRULWICH:
 
 Tom and Ray Magliozzi, the
 <cite>
 Car Talk
 </cite>
 guys from National Public Radio.



 RAY MAGLIOZZI:
 
 What was that whistling noise?



 ROBERT KRULWICH:
 
 Yeah, what is that whistling?



 RAY MAGLIOZZI:
 
 What's that about?



 ROBERT KRULWICH:
 
 Mmmmmm.



 TOM MAGLIOZZI:
 
 That sounds like F above middle C. I would like to open
the hood just to see what's there. Don't shut it off.



 RAY MAGLIOZZI:
 
 And don't lock the keys in it. I'll leave a window open.
I'm dying to see what's under here.



 TOM MAGLIOZZI:
 
 What the heck is this? See, I knew it. It's not an
engine!



 ROBERT KRULWICH:
 
 Well, it has a box, and it has lots of things
connecting to it.



 RAY MAGLIOZZI:
 
 Yeah, my intuition tells me this is an electric motor.



 TOM MAGLIOZZI:
 
 This is basically an electric car.



 RAY MAGLIOZZI:
 
 You know what it sounds like? It sounds like my Norge
refrigerator used to sound.



 ROBERT KRULWICH:
 
 Tom and Ray know a lot about regular cars,
the ones with internal combustion engines.


 This, on the other hand, is an electric car. But you don't plug it in,
instead, it's powered by this mysterious fuel cell thing.



 RAY MAGLIOZZI:
 
 This is stuff, this is technology that none of us
understands.



 TOM MAGLIOZZI:
 
 No one told us this.



 RAY MAGLIOZZI:
 
 Do we need help? We need help.



 ROBERT KRULWICH:
 
 Maybe we should ask...



 RAY MAGLIOZZI:
 
 We need someone, a passerby, just some ordinary
citizen.



 ROBERT KRULWICH:
 
 Dan.



 TOM MAGLIOZZI:
 
 Who?



 ROBERT KRULWICH:
 
 Oh, my god. Thank goodness the car comes with
its own expert, Dan Kelly, who works for a company that actually makes fuel
cells.



 RAY MAGLIOZZI:
 
 So it has an electric motor. What runs the motor?



 DAN KELLY
 
 : All the electricity comes from the fuel cell. And the fuel
cell is really made up of a collection of these.



 ROBERT KRULWICH:
 
 This is a fuel cell? It looks like a
black plastic license plate.



 DAN KELLY:
 
 This is one cell. And it's like a sandwich; you just stack
them up. You want more power, add more cells. Make a bigger sandwich. And what
goes through, if you look at it...



 RAY MAGLIOZZI:
 
 It's a piece of plastic!



 DAN KELLY:
 
 ...and the grooves that are in it...



 ROBERT KRULWICH:
 
 Yeah, what is this?



 DAN KELLY:
 
 ...you get...Hydrogen runs through these grooves.



 ROBERT KRULWICH:
 
 So what's really going on inside these little
holes? How is this thing making electricity?


 Well, inside the fuel cell, there are two sets of tiny passageways
separated by a membrane. And if you look very close, the two main sections are
kind of like the two sides of a tennis court. On one side is hydrogen and on
the other side oxygen, and then there's the membrane that separates them. It's
kind of like a net.


 So here we are in a tennis court. I, of course, you'll notice now,
represent the atom oxygen, and for those of you who are oxygen atoms
yourselves, you'll, of course, recognize that I have eight electrons. This is a
fuel cell, so oxygen is opposite hydrogen. There are two hydrogen atoms, and if
you'll rotate please, you'll see that they too each have one electron. Now it
is in the nature of this kind of chemistry that hydrogen and oxygen are
attracted to each other.



 RAY MAGLIOZZI:
 
 I yearn for you, Robert.



 ROBERT KRULWICH:
 
 You yearn for me, but there is a membrane
between us. Now the rules of the fuel cell are you will try to come to
me—try to come to me—but you'll have to go under or through the
membrane. Try under the membrane.



 TOM MAGLIOZZI:
 
 Try under. Okay.



 ROBERT KRULWICH:
 
 Down they go, the two hydrogen atoms
approaching the oxygen with ardor, but notice now...



 TOM MAGLIOZZI:
 
 We can do it! Robert, I love you!



 ROBERT KRULWICH:
 
 ...through the membrane...



 TOM MAGLIOZZI:
 
 We made it, Robert! We made it! Oh, my god, finally.



 ROBERT KRULWICH:
 
 Now, but—and I use the word "but"
advisedly—could you please rotate? So show the audience your butts at
this moment. You'll notice that this has got no electron; no electron here. The
question has to be asked, "Where are the electrons?"


 Remember when the hydrogen had to come through the membrane? Well, when it
did that, its electrons were stripped off. Electrons simply aren't allowed
through the membrane in a fuel cell.


 But they do want to come to the other side. So very cleverly, they go
around the membrane, right at the edge of the fuel cell, over and over and over
again. And moving electrons, well, that's electrical current. That's what
lights up a light bulb, or, in this case, what powers your car.


 And here's what makes the fuel cells so clean: after the electrons get to
the other side, they rejoin their old friends, hook up with the oxygen, and
before you know it, you've got H
 
 2
 
 O—water—pretty
neat.


 So in these cars, when you check the tailpipe, instead of exhaust, what you
get...



 RAY MAGLIOZZI:
 
 ...is water.



 ROBERT KRULWICH:
 
 Oh, how do you know?



 RAY MAGLIOZZI:
 
 'Cause it looks like water.



 TOM MAGLIOZZI:
 
 Take a drink. Lick it. Lick it!


 He's dead! I didn't like him anyway.



 ROBERT KRULWICH:
 
 The very idea that a car's motor could be
this clean has an enormous appeal, especially to certain politicians. They act
like it's going to be easy—well, sometimes they do—but as it turns
out, there's a catch, actually, a bunch of catches. Fuel cells are still very
expensive to make, they wear out more quickly. And, oh, yeah, there's another
thing...



 DANIEL NOCERA
 
 (Massachusetts Institute of Technology)
 
 :
 
 A fuel
cell needs fuel, so we've been talking about hydrogen and oxygen as our fuel.
There's lots of oxygen. But where are we going to get the hydrogen in the
first place?



 ROBERT KRULWICH:
 
 MIT chemistry professor, Dan Nocera, says,
"Remember, you've got to have pure hydrogen, all by itself, on one side of the
membrane to get things going."


 So where do you get pure hydrogen? Well, there's plenty of hydrogen on
earth; it's just not pure. It's stuck to other stuff, like oxygen, in water, of
course. And hydrogen can be found in fuels like natural gas, you know,
hydrocarbons.


 But if you take it out of there—and that's where most hydrogen comes
from today—you do get a waste product, carbon dioxide. And that's one of
the bad guys in global warming.


 So what's the answer?



 DANIEL NOCERA:
 
 I think water is the key for the future.



 ROBERT KRULWICH:
 
 Every high school chemistry student knows how
to split water into hydrogen and oxygen. You just run electricity through it.
That's electrolysis.


 But hydrogen and oxygen are so cozy and comfortable together, you use up so
much electricity prying them apart, it could cost a fortune. So we are facing a
significant technical problem here: how do we find a cheap, clean source of
hydrogen?


 Oh, and there is another issue...



 RAY MAGLIOZZI:
 
 Excuse us for a minute.



 TOM MAGLIOZZI:
 
 We'll be right back.



 ROBERT KRULWICH:
 
 Yeah. Don't we worry a little bit about the
danger problem?



 RAY MAGLIOZZI:
 
 What about the Hindenburg?



 ROBERT KRULWICH:
 
 Yeah, what about the Hinden...the huge
balloon the Germans...



 RAY MAGLIOZZI:
 
 Yeah. Oh, the humanity...the whole thing.



 TOM MAGLIOZZI:
 
 We've got to ask him.



 RAY MAGLIOZZI:
 
 Yeah, Come on.



 TOM MAGLIOZZI:
 
 Dan...



 RAY MAGLIOZZI:
 
 What about the Hindenburg? Remember the Hindenburg?



 TOM MAGLIOZZI:
 
 Yeah, what about the Hindenburg? Yeah.



 DAN KELLY:
 
 The Hindenburg?



 ROBERT KRULWICH:
 
 The Hindenburg pretty much ruined hydrogen's
reputation. But after the explosion, the fire here, the continuous flames that
you see, some say they came from the canvas blimp which was coated with highly
flammable shellac.



 DAN KELLY:
 
 Are you comfortable getting back in now?



 RAY MAGLIOZZI:
 
 Not really, no. I'll be walking back.



 ROBERT KRULWICH:
 
 One moment, one moment.


 Of course, gasoline is flammable, too, and we drive around with gallons of
that in our cars.


 It's something else about hydrogen...



 NATHAN LEWIS
 
 (California Institute of Technology)
 
 :
 
 Well,
hydrogen's a gas.



 ROBERT KRULWICH:
 
 Okay, so?



 NATHAN LEWIS:
 
 That means most of the space between the hydrogen
molecules is not useful to make energy. There's nothing there.



 ROBERT KRULWICH:
 
 So says Nate Lewis, a scientist at Caltech.


 Getting enough hydrogen into a car is a challenge, because it likes to
spread out, and you've got to squeeze a lot of it into a small place.


 You can't use an ordinary gas tank to hold it, because it would burst open.
And you wouldn't want that.


 Did I run a stop sign?



 RAY MAGLIOZZI:
 
 Noooooooo.



 ROBERT KRULWICH:
 
 No? All right.


 So the hydrogen tanks have to be super strong, to hold hydrogen squeezed in
at pressures up to five to ten thousand pounds per square inch. But even with
that special tank, it's tough to get enough hydrogen in the car. For instance,
to drive 300 miles, you might need a gas tank four times the size of the one
you've got now.


 Which leads Professor Lewis to suggest the best place for hydrogen fuel
might be in power stations, to light up cities and factories.


 After all, why rush to put this fuel out on the road, when you can easily
store plenty of it in a factory basement?


 So you're a put-it-in-the-basement guy?



 NATHAN LEWIS:
 
 Put it in the basement first. And then, if we ever figure
out how to use it to move us around, that will be great. But your car is the
last place that you want to put hydrogen.



 ROBERT KRULWICH:
 
 But the dream of a car that spews out nothing
but water is so appealing. And if we could use water to fuel the car, that
would be even better.



 TOM MAGLIOZZI:
 
 When the technology is really there, you'll be able to
open up that little gas fill and fill it up with water like my brother used to
do when he was a kid.



 DAN KELLY:
 
 Yeah. So the car will run...



 ROBERT KRULWICH:
 
 But the technology to get hydrogen from water
efficiently and affordably? That technology doesn't exist yet.


 Well, is there anything that we know of that does this regularly, that
breaks apart water and...?



 DANIEL NOCERA:
 
 We do. It's the leaf.



 ROBERT KRULWICH:
 
 The, the what?



 DANIEL NOCERA:
 
 Leaf.



 ROBERT KRULWICH:
 
 The leaf. It turns out the leaf is a pro at
splitting water. In photosynthesis, leaves take water and break it down. The
oxygen goes into the air—thank goodness, because that's what we
breathe—and the hydrogen hooks up with carbon to make carbohydrates,
which the plant needs for fuel. And the energy to do all this comes from the
sun.


 So does Dan Nocera want to "make like a leaf?"



 DANIEL NOCERA:
 
 So what we've been doing is trying to actually, not
duplicate what a leaf does, but we're saying, "Can we generate hydrogen and
oxygen by entirely new ways?"



 ROBERT KRULWICH:
 
 In his lab, lasers stand in for the
sun.



 DANIEL NOCERA:
 
 What we do is we bring this laser beam in, and now you
see, actually, here's a compound that's capturing that green light.



 ROBERT KRULWICH:
 
 So this is your version of sunshine, and this
is your version of something that sunshine is acting on?


 The laser shoots through a liquid mixture concocted in Nocera's lab. He's
trying to design a chemical, something like this pink peapod thing, that does a
special trick, so when light hits it, it will pull apart the H from the
O.


 Have you ever taken a droplet of water and found a way to just release
hydrogen?



 DANIEL NOCERA:
 
 We haven't done water, but we've done hydrochloric acid
and we've been able to make hydrogen.



 ROBERT KRULWICH:
 
 So that's a "no." But there are labs all over
the country now working on hydrogen. Some work with algae, some with solar
collectors. And these guys are making hydrogen from water and sunlight.


 But at least for now, it's very expensive. And just last year, the National
Academy of Engineering and the National Research Council reported there are
"major hurdles" on the path to a hydrogen economy, and that clearing them "will
not be simple."


 So even though the President is saying we could have hydrogen cars for
today's generation...



 GEORGE W. BUSH:
 
 The first car driven by a child born today could be
powered by hydrogen and pollution-free.



 ROBERT KRULWICH:
 
 If the car's really going to be
pollution-free, the hydrogen in the tank will have to come from a clean source,
and so far, when it comes to splitting water, we're way behind the leaf.


 Dan and other scientists are trying to catch up and will keep trying, but
the secret, he thinks, may be very subtle.


 So how long did it take for the leaf to figure out how to separate hydrogen
from oxygen?



 DANIEL NOCERA:
 
 That took between two and four billion years.



 ROBERT KRULWICH:
 
 But how much time do you have?



 DANIEL NOCERA:
 
 I'm guessing around 20 more years.



 ROBERT KRULWICH:
 
 And so, whatever the politicians may say,
learning to "make like a leaf" could take a while.


 Okay, so we do have time then for a very short puzzle? This one lasts fifty
seconds, exactly, unless, of course, you happened to guess the answer earlier.



 MAN:
 
 The key ingredient of this substance was originally extracted from
the sapodilla tree. Nowadays, the formulation is coated with fine particles of
sucrose and enclosed by a thin layer of aluminum seven microns thick. It
contains synthetic materials blended with natural products, such as leche caspi
and masuranduba. On contact with the enzyme amylase, secreted by glands
in the buckle cavity, its texture is transformed to a malleable compound with
elastic properties. After several minutes grinding in a heterodont interface,
oral fatigue often leads to removal of the sticky molecular structure and
adhesion to a suitable surface.



 ROBERT KRULWICH:
 
 Well, if you got that one, we do have another
one at the end of program. It involves a filter-feeding sedentary metazoan. We
think you'll probably want to stick around for that.
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