Car Tech 101: Another kind of electric car: Hydrogen fuel cell
-Now we talk about a hydrogen fuel cell vehicle today, a couple things to understand.
We're talking about a PEM fuel cell, Proton Exchange Membrane.
That's what goes on inside this box-shaped thing about [unk], it's not very large.
Secondly, it's hydrogen fuel, in other words, you're putting hydrogen in on one side to create the chemical reaction that generates the electricity.
Hydrogen from a tank in the car, if exposed to a plate coated in platinum on one side
of a sort of sandwich, the platinum plate causes the hydrogen to break up into protons and negative electrons.
A membrane in the middle of this sandwich only allows the positive ones to get through, so those negative electrons have to go around.
That circuit creates the positive and negative poles, the potential that makes the electric current.
When the electrons and protons do meet on the other side, they combine with oxygen from the air to form H2O and a huge PR whim for hydrogen backers.
So what's it like driving a fuel cell car?
Just like driving an electric car, because remember, a fuel cell is a source of electricity powered by a very clean, very abundant fuel, but it is not the powertrain source that moves the car.
That's a difference.
So really what it comes down to is electric cars that fork two ways: one toward hydrogen fuel cell, one toward battery electric.
The big difference here is when you go to refill, it's a whole another world.
So, the benefits--
number one, clean.
Hydrogen fuel cell electric cars emit nothing but water vapor and not much of it.
This is like a week's worth of driving and yes, it is clean enough to drink.
Number two, renewable.
Hydrogen is the most abundant thing on Earth.
I'm told 75 percent of the mass of the planet is hydrogen.
-It's bound in things all around us.
It's bound in water, it's bound in plant material, and it's bound in everything that's a hydrocarbon.
Refilling a hydrogen fuel cell car takes a few minutes at the pump, compared to hours plugged in for most electric charges.
-It's quick, clean, and easy and that you're on your way in less than 5 minutes.
-Now, some challenges.
First, distribution-- hydrogen to be useful as a fuel in a fuel cell car needs to be highly compressed, but naturally it wants to be 14 times lighter than air, it wants to be very gaseous and low density.
So, it's got to be
It's got to be created.
Has to be compressed, has to be kept in that state from the point where it's stored to the point where it's put into the vehicle.
That makes it trickier than gasoline, which is very happy to be this oily liquid that lives underneath your service station.
Durability-- current hydrogen fuel cells are good for maybe a hundred thousand miles before they're spent.
That's rather below what consumers expect from a gas or diesel.
Number three, pollution-- now, I've just told you that hydrogen fuel cell cars are incredibly clean, but creating the hydrogen may not be,
depending where you live and what kind of a source your local filling station has for the hydrogen, there is upstream pollution created.
Much as there is with battery electric cars.
It will vary widely by how and where you refill.
The Holy Grail is to run solar-powered plants that crack water into hydrogen making no upstream pollution and using a virtually unlimited resource.
-This station in Emeryville makes its hydrogen from solar power and water in a process called electrolysis.
Other stations make their fuel on site, for instance from waste water or even landfill gas.
Fuel cells, catalytic converters, and wedding rings-- none of them are cheap because they all use a bunch of platinum.
-Divine Automakers who are members of the Fuel Cell Partnership are starting to introduce their commercial vehicles.
Some of them are for lease now in limited areas where there are stations, but we're hearing them talk about starting to sell them in just about 18 months in 2015.
-That's sort of OEM lost leadership will be key.
But perhaps more than any other alternative vehicle, hydrogen fuel cell cars will need leadership from government to foster a new network of fuelling points and supporting infrastructure.