Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Hydrogen fuel cells!

  1. Sep 1, 2007 #1
    Hi! I'm django, new member. Right, I would like to talk about fuel cells. At first glance they are great, right! 99% fuel efficieny. But what most peopkle don't realise, is that although hydrogen might well be the most predominant element in the Universe, it is not available on earth in significant amounts! Imagine a surveyor finding a vast field of Hydrogen gas, he drills a hole and Psssht!!! it's gone, no hydrogen. The point I'm trying to make , is that it's like sticking your finger in a hole in a dike, right! It just does not do any good, there are not naturally occuring hydrogen gas deposits, as there are of other petrochemicals. So the only way to get hydrogen is by cracking hydrocarbon fuels that are already available, such as petroleum, methane or some other such fuels in hydrocarbon deposits, which is a task that is both wasteful, time consuming and just not worth it in the long run. Any comments? django
    Last edited: Sep 1, 2007
  2. jcsd
  3. Sep 1, 2007 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    You're missing the entire point of the hydrogen fuel cell. Hydrogen is not intended to be a fuel -- you're not going to go retrieve hydrogen from the earth and then use it in your car, the way we do gasoline.

    Instead, hydrogen is a form of energy storage and a form of energy transport. A hydrogen fuel cell is just like a very high-capacity chemical battery.

    You can use any energy source you like (solar, fission, fusion, etc.) to break water into hydrogen and oxygen. You can then transport and store the hydrogen, and use it in your car. Your car recombines it with oxygen, and you get water out of the tail pipe.

    If you use fusion energy to liberate hydrogen, you might as well say your car is "fusion-powered." The hydrogen is just used as an energy transport. It's obviously much more cost-effective (and safer) to build one large fusion plant than it is to try to equip everyone's car with a fusor.

    As compared to other forms of energy storage, like conventional chemical batteries, fuel cells can have much greater energy densities, much faster "recharge" times, virtually unlimited service lifetimes, and much larger capacities. In other words, hydrogen fuel cells are just really good batteries. That's all. Nothing more, nothing less.

    - Warren
  4. Sep 1, 2007 #3
    point taken. django
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook