国家地理-2008-05-24 Fuel Cell 聚焦燃料电池（在线收听）

For something that could revolutionize the world, it’s come along very slowly. The fuel cell was invented in 1839, but there was little development until the 1950s when NASA started to use them in space where they are still used today. Now, after years of continuous development, things are speeding up.

At its core, the fuel cell is very simple. It uses hydrogen, the most abundant element in the universe , as fuel. One type of fuel cell uses a membrane and it looks something like plastic wrap . It allows the hydrogen’s proton to pass through while the electron is forced to take a different course. This produces electricity. The fuel cell runs as long as it’s fed hydrogen. The cleanest, the most readily available source of hydrogen is very easy to find. It’s water. Of course, it couldn’t be this simple. Somehow, the hydrogen in the water molecule must be stripped and stored, and that takes power.

Peter Lehman at Humboldt State University in Northern California decided to build a renewable hydrogen fuel cell system for a research aquarium.

“I think the legacy of the 20th century is that we were very good at burning things. Fuel cells offer a clean and efficient way to generate electricity. They are totally pollution-free and they are significantly more efficient than traditional ways of generating electricity.”

He bought solar panels to provide power to remove the hydrogen from water and tanks to store the hydrogen fuel. The problem was the fuel cell. No one produced one that would work with the aquarium. So Peter went ahead and built it. During the day, it uses power from the solar panels, but only part of that power. The rest is turned into hydrogen for use later by the fuel cell. That creates a completely renewable full-time system. The goal of fuel cell makers is to offer totally reliable, independent systems, but the competition is tough. To thrive in the marketplace, fuel cell makers must compete against the cheap and reliable power provided by fossil fuels. Peter’s reliable fuel cell system has already satisfied customers who are off the power grid. Now, he’s ready to convince the rest of us.

Vocabulary Mix 
membrane  A thin sheet of natural or synthetic material that is permeable to substances in solution.