Can Urine Rescue Hydrogen-Powered Cars?

thecarchik writes with this interesting excerpt: "It takes a lot of energy to split hydrogen out from the other atoms to which it binds, either in natural gas or water. Which means energy analysts are skeptical about the overall energy balance of cars fueled by hydrogen. Ohio University researcher Geraldine Botte has come up with a nickel-based electrode to oxidize (NH2)2CO, otherwise known as urea, the major component of animal urine. Because urea's four hydrogen atoms are less tightly bound to nitrogen than the hydrogen bound to oxygen in water molecules, it takes less energy to break them apart."

Comments

Re:Uh, the chemistry

[adonoman]

It only works that way in a self-sustaining reaction (one that produces enough energy to keep itself going). In this case, the hydrogen is being used to store energy, so the process is going to require input energy the whole time. They're taking from a lower energy state and pushing it up to a higher energy state so that at a future time, you can add in that bit of activation and let the reaction go, giving you energy in the process. It''s like pushing a rock up the hill - when you get it to the top, you can use all that stored energy just by giving the rock a little tap and letting it roll down. The advantage of using urea over water as a source of hydrogen, is that with urea, less energy is required to separate out the hydrogen. It's like starting pushing the rock from halfway up the hill.