What are the benefits of hydorgen cars?

Question

I'm doing a paper on hydrogen as an alternative fuel and i know that hydrogen care are the next thing. So I was wondering what the benefits about it would be

Answer 1

When hydrogen is used as a fuel, either by combustion or fuel cell, then we have an energy source that would recycle itself.

Hydrogen can be extracted from water, when hydrogen burns, it also produces water as a byproduct.

Answer 2

The environmental benefit of hydrogen cars depends entirely on where you get the hydrogen from.

Currently the only reasonably efficient way to get hydrogen is to extract it from natural gas.  However, this process creates more CO2 emissions than burning gasoline, and it's also more expensive.

Theoretically you can get hydrogen from water by breaking its bonds with the oxygen, but this requires a ton of energy.  You have to put in more energy than you can get out by burning the hydrogen.  If there were some way to efficiently get the hydrogen from water, you would have a very clean process.  The input would be water, and the output would be energy for your car and water vapor.  The problem is how to break the bonds in the water molecules though.

There is another possibility - adding water to an aluminum-gallium alloy produces hydrogen as a biproduct.

http://www.physorg.com/news98556080.html

So this could potentially work, because aluminum is a cheap and plentiful resource.  At the moment they're only trying to use this technology in small engines (like lawnmowers) to see if it works.  If it does, they'll try to scale it up to larger engines for cars, and you'll have an environmentally friendly source of hydrogen.  There are some issues with the amount of heat produced during the the reaction between the water and aluminum alloy, so it's not sure to work, but it's fairly promising.

Bottom line is that hydrogen cars won't be available for probably at leat 20 years.  In the meantime we should be focusing on development of hybrids and electric cars.

Answer 3

the benefits of hydrogen car is a clean engine that helps our world clean, second our world would no longer depend to much on other oil products, third it's a fruit of the growing knowledge, forth it's the future engine  vehicle ecc. in united  states their are stations for hydrogen fuel. in germany too they have.

Answer 4

As far as I know, a hydrogen car would have essentially zero emissions.  Hydrogen burns to produce heat and water.

Another benefit would be a nearly inexhaustable source of fuel.  Pure hydrogen can be removed from water.  We have some of that water stuff around here somewhere....

Answer 5

I believe the links below will explain the answers to your question sufficiently.

Answer 6

Hydrogen can be taken from water so it is renewable.  We don't have to spend bazillions drilling for oil.  Also, hydrogen vehicles only emit water vapor.  If they could make a car that you just pump water from the hose into and it creates hydrogen we would be set.  I think it's great and don't see why we don't have it yet.  The only reason I can think of is that the government is run by the oil industry.

Answer 7

Hydrogen Cars run on hydrogen,  and emits only water vapor. There's also some talk about GM, (i think) putting some on the road in the D.C area. (maybe??)

Answer 8

Apart from the net inefficiency of making the d**n stuff (even H2O/Al redox is c**p because aluminium requires LOTS of electricity to refine), in fact all methods of producing H2 are fairly horrible from an energy efficiency perspective, there is another problem:

Hydrogen has a very low energy density per unit volume unless you crank the pressure way up (~5000PSI for the tank design Bosh were advertising a few years back), or go cryogenic which does bad things to the energy efficiency as you need something of the order of the same energy given by burning the hydrogen to liquefy the stuff (meaning 50% efficiency before you even get an engine involved). Then you have the issues of transporting a bulky flammable gas (or cryogenic liquid at a few kelvin) from where it is produced to the cars and devising a safe filling mechanism...

There has been some work done on metal hydrides as storage, but the density really is not there.

Now there has been work done on reforming methanol (gives H2, CO2, CO and H20) on the vehicle and using the H2 to run a fuel cell, but that technology has some fairly nasty issues (cost of the cell stack first and foremost, also startup time and inefficiency for short trips (You have to heat the cell stack to ~80C before it starts producing useful power)), it might some day become sane for long haul trucking and possibly for trains where electric railways cannot be directly used for whatever reason, but I really don't see it for passenger cars.

Look into the 'think' project done by IIRC Ford and GM, for the gory details. It was an open secret that this was done, not because it was going to give us workable hydrogen cars, but as a sop to the Californian government (It was easier then buying the politicians).  

Hydrogen is at best (if they manage to solve the storage and transport issues) a somewhat more portable intermediate step between large electrical generators/chemical plants and the prime mover on the vehicle (but every conversion costs you overall efficiency).

Now, a thermal power station is somewhere between (~40% (nuclear) and 55% (state of the art gas)) efficient, so anything you do with electricity has to allow for the fact that you are starting off with ~50% of the energy you put into the system... So for a gas fired plant, and assuming that the production, transport, and compression for the cars tank do not require any energy input (ha!), the cars engine would have to be around twice as efficient running hydrogen then running propane before you see any net benefit. Now liquefied propane gas is mature technology and could be a reasonable place to go.  

The fuel cell might one day replace the IC engine as it bypasses the thermodynamic efficiency limit of the Carnot cycle, but I would bet it runs on methanol rather then H2 (much easier to handle and store).

I would raise serious doubts about your underlying assumption that hydrogen cars are 'the next thing'. Getting US diesel (and diesel engines) dragged kicking and screaming into the 21st century would be my bet for the next thing.  

Regards, Dan.

Answer 9

Hydrogen ICEs (Internal Combustion Engines) can run at super high RPMs. 10x that of gasoline engines.

Hydrogen ICEs can burn at a temperature below the point that creates nitrogen oxides.

Hydrogen ICEs are very efficient.

Hydrogen fuel cell cars will be very efficient.

NOTE: Hydrogen is an energy Carrier! Not a fuel source. We cannot drill, mine, or gather hydrogen. It must be made from natural gas, electolysis of water, or various other ways. More than likely, coal power plants will produce hydrogen through electrolysis with the electricity they produce at night when few use it. The power companies might pipeline it into town where it could be sold at an Exxon or Shell station.

Just my prediction.

What do I know, I'm 13

Answer 10

Some hydrogen cars don't burn oxygen. 3.8 liter car gasoline engine idols at 1500 per minute. Your brain may be surprised. It is a first for the decrease in oxygen by this method this has never happen to the atmosphere before. Is the world like a big balloon in space? Global warming, CO2 is heaver than air and is at-tracked to the gravity of the earth or even to the sun, maybe, maybe not? Your children even breath oxygen to add to oxygen deficiency and will build more wooden homes