Fuel Cells explained to an English major

With the upcoming release of Bloom Energy's mind-blowing, life-altering fuel cell system that will bring our country's climate and energy crisis to an end, the Fourth Corner went looking for an explanation of what the hell a fuel cell is. We turned to our friend and contributor, Gene, who is a science engineering buff who can explain things in terms that even our Editor-in-Chief, Rob understands. So, for those of you without an advanced degree, here is what a fuel cell is for the layman. (Note: Bloom Energy is supposed to change the world, just like the segway was supposed to change the world. Both inventions were financed by the same guy.)

The Sex Lives of Hydrogen

I'm also no expert in chemistry or material science, but I'll explain the basics of what I know. So, when you normally want to use fuel, you burn it, right? Hydrogen and carbon atoms make up molecules in the fuel that break down, reacting with oxygen in the air, producing H20 and CO2, and a lot of heat. As these hydrogen and carbon atoms leave each other to go hook up with sexy
oxygen molecules, they take their electrons with them. The useful energy you get is in the form of heat and expanding gasses. There's no electrical component to it.

In a fuel cell, there's a similar process going on where hydrogen hooks up with oxygen. However, it's not done by lighting it on fire. What you do is keep your hydrogen and oxygen separated by a fancy wall. You then force your hydrogen nuclei (single protons) to squeeze through tiny holes in that fancy wall so that they can get jiggy with oxygen atoms on the other side of the wall. Being a very fancy wall, it will let the hydrogen protons through, but it won't allow through the electrons that once orbited those hydrogen nuclei. So, on the side of the fancy wall with the oxygen, you end up with a lot of extra hydrogen protons (positive charge). On the hydrogen-only side, you end up with a lot of extra electrons (negative charge). By electrically connecting the two sides, you create a path for electron flow, and thus you get electrical current! And between the two side, you can make those electrons go through whatever circuit you want to run a motor, power a computer, etc. Make sense? So a fuel cell can turn chemical energy (like the oxidation of hydrogen) into electrical energy very efficiently because you're directly getting use of the movement of the electrons involved in the chemical reaction. I hope this helps.