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Green Revolution: Hydrogen

6 minutes

(Describer) In an animation, different colored icons include a car, a house, a model for hydrogen, and an arrow that looks like lightning. In another one, a woman connects cables. As she laughs and smiles, title: Green Revolution, with Lisa Van Pay PhD (Scientist).

(Describer) Other icons: House with a grid on the roof plus waves divided by lightning with an arrow equals question mark. Title: Hydrogen

(Describer) In an animation, a light with a minus sign goes around a ball with a plus sign.

(Lisa Van Pay) It's odorless, it's colorless and lighter than air. It's also the main ingredient in star formation. And it contains a lot of energy. How much energy? Enough to power the sun. It's energy we want for powering many things-- from cars and houses to laptops and cell phones. It's hydrogen, the most abundant element on Earth.

(Describer) Its icon is an H with the minus sign orbiting the plus sign. Title: are we using hydrogen already?

(Describer) A Space Shuttle takes off from a launch pad.

Well, it turns out we are. We already use hydrogen to power space shuttles, and several car companies have built hydrogen-fueled cars. Some are already on the road. There are even hydrogen-powered busses, boats, and airplanes. But unlike other fuel sources, hydrogen can't be harvested easily because hydrogen gas is very rare in our atmosphere. Due to its light weight, most escapes Earth's gravity. So instead, we have to make it. That can use a lot of energy.

(Describer) Yogi Surendrath, MIT:

You can make it by splitting water into hydrogen and oxygen. This setup is designed specifically to split water into hydrogen and oxygen-- the basic process of what's called electrolysis.

(Describer) A stick bubbles in liquid.

The name of the game, scientifically, is how to do that with minimal energy input, so none is wasted, while still having a fast enough reaction, so there's enough hydrogen for a day's use or whatever you want? The key is how to make the reaction fast without applying more energy. You do that by using a catalyst. A catalyst accelerates the reaction without needing you to apply more additional energy that might be wasted.

(Van Pay) Even with a catalyst, electrolysis, or the splitting of water into hydrogen and oxygen, still requires electricity to drive the reaction. Unless that electricity is green in the first place, making hydrogen gas isn't a completely clean process. The key is taking sunlight and converting it into electrical energy, then storing it in the form of chemical fuel, like hydrogen and oxygen, and then using those fuels in fuel cells, converting them back into electrical energy to use when the sun doesn't shine.

(Van Pay) Fuel cells are like batteries, except that as long as we keep adding hydrogen, cells won't run down or need recharging.

(Surendranath) We're trying to discover ways to have energy come from the house, to have your house be a power plant and the source of all fuel needed to run your life.

(Describer) Title: how can we turn hydrogen into electricity? In an animation, a sideways, fat capital letter H has a handle.

(Van Pay) A single fuel cell consists of a positive electrode, a negative electrode, a membrane, a catalyst, and a wire circuit outside the cell.

(Describer) The handle.

It works like this: Hydrogen enters the fuel cell, reacting with a catalyst at the anode. This helps separate the electrons from the protons. The positively-charged hydrogen ions, protons, can pass through the membrane. As the electrons build up, they start to push against each other, like repelling magnets. Eventually, they push each other through the path of least resistance-- across the wire circuit. This flow of electrons is electricity. When they reach the other side of the fuel cell, the electrons reconnect with the positively-charged protons, and combine with oxygen to form water.

(Describer) A woman writes on a clear board.

(woman) In here, basically, we have fuel cells, where you have hydrogen molecules

(Describer) ...on a table in front of her.

coming in from one side, and oxygen molecules coming in from air.

(Describer) Yang Shao-Horn, MIT:

Within the heart of the fuel cell, we have two catalyst layers, and we have ion-conducting membranes in between. On one side, we're splitting hydrogen molecules, and the other, we're splitting oxygen molecules. They combine to form water. At the same time, we generate electricity.

(Van Pay) We're getting energy out, then the only waste is water? Right. Perfect.

(Describer) Solar panels are on a roof.

(Van Pay) By turning our houses into hydrogen gas stations, we would have fuel for everything, even our cars, without harming the environment. It's a simple idea too. Store excess energy by day, then use a fuel cell to convert that energy into electricity at night. If I'm converting water into hydrogen to fuel my house and my life, how much water do I need?

(Describer) Surendrath:

Chemical bonds are really strong. You store a lot of energy when making hydrogen gas. You don't need much water. Just a few liters of water converted into hydrogen and oxygen is plenty for an entire day for a typical house.

(Van Pay) Someday, all our houses, offices and schools might be mini-hydrogen power plants that we can use to fuel our lives. Sometimes, it only takes a little to do a lot.

(Describer) Lisa rolls a small ball down a ramp into a cup, which lowers, pulling up a plate to release a toy car, which rolls forward and taps a domino that topples lines of different colored dominoes.

(Describer) Viewed from above, they spell NSF.

(Describer) Icons: House with a grid on the roof plus waves divided by lightning with an arrow equals hydrogen with O2 separate.

(Describer) Titles: Produced by Lisa Van Pay, Maria Zacharias.

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Host Lisa Van Pay meets with NSF-funded scientists Yang-Shao Horn and Yogi Surendranath at the Massachusetts Institute of Technology as they take on the hydrogen energy challenge.

Media Details

Runtime: 6 minutes

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