What's a hydrogen fuel cell? It's a battery that depends on oxygen and pure hydrogen gas to convert chemical energy into electrical energy. It's portable and energy efficient, and produces only water and heat as waste products -- all qualities that make it one of the future's brightest alternative energy options.
Sounds great, right? But why isn't there a hydrogen fuel cell inside every home, car and laptop on the planet? The answer lies in the technology's key shortfall: It depends on pure hydrogen gas, and there's virtually none of that on planet Earth. All the hydrogen at our fingertips is already oxidized or tied up in fossil fuel hydrocarbons, so the challenge becomes unlocking that hydrogen gas without depending on oil or spending excessive energy in the process.
The buzz around hydrogen fuel-cell technology often relates to automobiles -- and, indeed, the notion of a pocket-sized fuel cell used to seem a bit silly. Hydrogen gas has been notoriously difficult to store, requiring a pressurized steel tank. But myFC and SiGNa Chemistry took a different approach, choosing to harvest the gas via chemical reaction. So instead of having to store volatile hydrogen gas in sealed tools, a PowerTrekk user can just collect it from where nature stores it: good old H20.
The top half of the PowerTrekk contains the system's fuel cell, interface and USB hookups. It also features a separate battery that can work independently of the fuel cell or in unison as an energy storage buffer. The bottom half features two compartments: one for water and one for an inserted fuel puck containing sodium silicide, produced from sand and table salt [source: Sorensen].
When the sodium silicide (NaSi) comes in contact with water (H2O), the resulting chemical reaction releases aqueous sodium silicate (Na2Si2O5), hydrogen gas (H2) and energy (kilojoules per mole). It all breaks down like this [source: Sorensen]:
2NaSi + 5H2O -> Na2Si2O5 + 5H2 + 350 kJ/mol
But I know what you're wondering: How much does it cost? Can I bring it on an airplane? If I drop it in the sea will it convert the world's oceans to hydrogen gas?
Let's find out.