Is hydrogen fuel cell efficent enough?

Question

I watched a documentary on hydrogen cars, and am now very interested in the future of cars. Later, however i got into an intense argument with my dad about it; he's a BIG skeptic. He said that because nothing is 100 percent energy efficient plus we can never truly create energy, simply by putting water into a car would never work! I argued that gasoline, by that logic, wouldn't make cars run. He said that gasoline is made by enormous amount of energy and can therefore release that energy by simply lighting it. I understand that water, unlike gasoline, is not an energy carrier and to make energy carrier (hydrogen) from requires energy itself. so can hydrogen fuel cell really work?

Answer 1

Well i don't know much about that.  But i've heard that it takes as much gasoline to make the hydrogen cells as it takes to drive a car.  You might want to research that.

Answer 2

I think I understand this.

It's true that you don't stick water in your car, you put in hydrogen.

The hydrogen is made by electrocuting the water, which separates it into hydrogen and oxygen. The hydrogen, when it passes through the fuel cell recombines with oxygen, and this process releases energy basically.

So the hydrogen is like a battery, the most efficient type of energy storage that we know if as I recall. Almost all of the energy used to make the hydrogen can be recouped from the fuel cell, thus why it's appealing technology.

You can also combust it like gasoline, which is what's being done with the hydrogen 7 car by bmw.

Basically gasoline or hydrogen have stored energy. You refine oil to make gasoline, which you can use in your car. You also basically refine hydrogen from water.

It's also more appealing than gasoline because unlike gasoline we have lots of water, and the byproduct is water when it recombines with oxygen. So you use water to make it, and it emits water after it uses it, so in a way it's more cyclical than gasoline, which you burn and it turns into a gas from which you can no longer recoup energy.

Answer 3

The simple transfer of energy from different forms will cost energy(in the form of heat,or sound,or vibration,etc.),so there is no man-made way to produce 100% efficiency as yet,but it is possible to make hydrogen cells that are more efficient than gas,the problem is that the companies and governments have to work together to make it work,so good luck.

Answer 4

The Hydrogen Car Company will convert your internal combustion gasoline engine to run on hydrogen or you can buy a new car from them that has an internal combustion engine that is converted to run on hydrogen.

This is much less expensive than using a fuel cell which costs several hundred thousand dollars for a fuel cell large enough to operate a full size sedan. A fuel cell for a small economy car is over one hundred thousand dollars.

You can buy electrolysis equipment to produce hydrogen from water. The equipement uses approximately 50 kilowatt hours of electricity to rpoduce an amount of hydrogen with the energy equivalency of one gallon of gasoline.

Answer 5

yes hydrogen cars work, but... the way to get power u have to first off use gasoline to make hydrogen. so like your dad said nothing is 100% efficient. so really u just lost power b/c u went to hydrogen. u would be better off with gasoline really. u dont loose any energy by converting anything. hydrogen isnt clean, its still putting c**p in the air.

Answer 6

What your father is talking about is the efficiency of converting from one form of energy to another there are always losses, energy that doesn't get changed into the form we want.  But a fuel cell changes chemical energy to electricity and then to motion (2 conversions) while a gas engine turns chemical to heat to differential pressure to motion (3 conversions) + there are big losses in the transmission.  A fuel cell / electric motor is more efficient than a gas engine.

The problem is the weight.  For the amount of energy they produce they are really heavy (100X more weight for the same HP).  They might be good for a hybrid train (which they are used for now), but not great for a car.  

And the car would not burn water.  The water would be broken down by electrolysis into H2 + O, which could be driven by green power sources; the H2 only would be used in the fuel cell.

The point is, it doesn't matter if there is less energy per litre of H2 than per litre of gas, a hydrogen fuel cell doesn't produce green house gasses.

Answer 7

An electric motor is about 50% efficient at its peak.  This means that 50% of the energy that goes into it is transformed into the desired mechanical equivalent.  The other 50% is lost as heat in the electrical wires (copper at environmental temperatures is a good conductor, but it's not a superconductor), etc.  A lot of energy would also be lost in the fuel cell as heat.

An internal combustion engine is only about 35% efficient (ballpark figure) at its peak.  The other 65% is lost as heat.  

If you can get them, tally up the losses involved in the fuel cell and the electric motor on one hand and in the internal combustion engine on the other hand.  You'll find which approach is most efficient.  (Checking out the references, it seems that a fuel-cell vehicle would only be around 17 or 18% efficient, but maybe I'm missing something.)

With that in mind, consider that both approaches will produce ozone because of the electric motors, and the internal combustion engine could produce nitrogen dioxide gas (NO2).  The fuel cell itself only releases water and heat, if it is hydrogen-based.

It's a lot more energy efficient to tap petroleum deposits than to split water into hydrogen and oxygen because the atoms in the water molecule are so tightly bound.  

If you're going to obtain your hydrogen by using fossil fuels, you're just making the whole transportation process more expensive and less efficient.  If, however, you could use electricity generated by nuclear fuels or by solar energy, you might end up a little ahead of the game.

Your father's right, by the way.  A liter of gasoline packs a lot more power than a liter of compressed hydrogen.

The best compromise of all might be to use natural gas fuel cells to power vehicles, since natural gas is readily available and packs more power per unit volume than hydrogen does.  Southern California Gas Company and its owner, Sempra Energy, are looking into this.

Another compromise would be to use natural gas to either replace or supplement gasoline in existing internal combustion engines.  A conversion kit or process is a lot cheaper than a new vehicle.  I also heard an unsubstantiated claim that using natural gas as an internal combustion vehicle fuel eliminates petrochemical smog and produces no carbon monoxide.  This would be worth checking out to verify or debunk it.

Hope this helps.

Answer 8

Depends on what kind of energy your trying to get from hydrogen check this out and email the guy . He is in the field of cold fusion from hydrogen check his site out and get his email address and email him im sure he will be happy to answer any questions you have about hydrogen and way of extracting energy from it . Hydrogen Carey's allot of energy look at the hydrogen bomb its just figuring out how to control it . The problem is most people want to see before they believe that anything exist although its just under there nose

   www.first-molecule.com Alternative Energy Co.

Answer 9

I believe your dad is right. Also H2 is very dangerous to store and handle. I doubt it would be approved for use due to safety requirements anyway.