Hydrogen powered cars

Having just seen yet another news article on how hydrogen powered cars are going to solve climate change, I thought I'd post a quick question.

Once you realise that the boasts of zero harmful exhaust emmisions, are weakened somewhat by the fact that considerable energy (and therefore emmisions), is required to produce the hydrogen before it even gets into the car:

are there any positive environmental aspects to cars powered by hydrogen, rather than by petrol?

(obviously there's possible benefits to manufacturers/governents as it enables car manufacturing to continue even when oil runs out; but what I'm asking about are environmental benefits).

You can create hydrogen yourself by passing a small current into water, it bubbles oxygen on one side and hydrogen on the other. This can be done quite easily using renewable methods.

I've been thinking along the sam elines for years, Dave.

Theres any number of technologies to power vehicles other than jus oil-based internal combustion.

What is needed in my opnion, is locally based, low-pollutant/emission ways of generating the energy needed for these and all othe rpower needs.

The advantage of hydrogen for the future, is that the energy generation process may be cleaned up, meaning less emmissions in the future if the technology arrives.

With oil-based fuels, you know what will be coming out of the exhaust, so the ability to minimise that is much less than the hydrogen generation that may come about in the future.

To me, though, its not about alternative fuels, its about local generation of energy, no matter what type it is.

To dig up oil in Texas, and ship it halfway around the world to the UK, uses a massive percentage of energy, just to transport the energy from its source, to where it may be used to power something, a car, home-furnace, power plant or whatever.

The energy cost (and currently pollutant cost associate with the curren technology) expending thousands of litres of oil, just to transport millions of litres of oil to a dock, then pumped into different containers, put on trucks and trains or pipelines, shipped to a processing plant, shipped back to a wholesaler, then shipped to a petrol station, then FINALLY pumped into someones gas tank, its just plain silly.

Even the petrol pump is using energy to transfer the oil, calculate the cost etc etc.

This use of energy to transport energy to where the energy might be consumed starts to eat away at your brain after a while.


The key solution, is to find ways of producing locally viable energy sources, to cut unneccesary transport of energy down to a bare minimum. The energy savings would be real, instant, and there would be no emmissions at all for the reduction.

Does that make sense?

I'm holding out for room temp superconductors. Thousand kilowatt electric motor that fits in your pocket? that'll be twenty dollars, thanks.

more on topic:

I reckon anything'd have to be an improvement over petrol/diesel. At the moment, there's wasted resources in the obtaining of petrol and the use. If a similar amount of energy/resources goes into creating a fuel that doesn't pollute, then i reckon we'd be better off. Petrol pollutes twice, hydrogen pollutes once. Not a bad thing, i dont think.

This is true. I'm gonna keep thinking that no matter what, there's going to be one step less pollution than with petrol, because there's no end emissions. Chances are, the same power source for the refineries currently used for petrol will be used to 'refine' the hydrogen.

Ideally, nothing would produce any emissions anywhere along the stage of its life. Unfortunately, i don't think i'll see that in my life. I'd like to, sure, but i don't reckon i will.

Cold fusion would be nice... Especially if they shrank it enough to become almost portable.

i thought that they had one that was around -50 deg C?

It need to be mentioned that the actual production of a hydrogen fueled car is also an evironmentally distructive thing. Personally I think the age of cheap personal automobiles will probably come to an end unless there is a massive acceleration in the renewable technologies.

there a principle used to look at envrionmental impact called 'Life Cycle Analysi's - particularly used in the environmental engineering area.
It involves looking at the broader impact of a product that you use from all aspects - creation, transportation, use, and disposal. for instance, whats the point in using you car to drive to the local shops to buy a packet of recycled envelopes?

hydrogen powered cars sound great in principle - but when you look at where you get the oxygen and hydrogen from in the first place - it changes things. sure you can get hydrogen from passing an electric current from water - but that current is likely to be generated by a fossil fuel pumpin power plant.

it may seem to be environmentally friendly to have a car with no emissions that makes water, but down the chain it just means that the local power station will be pumping out more fumes in someone elses neighbourhood.

HERE IS THE CORRECTED VERSION DONE WHEN I AM PROPERLY AWAKE

Some quick calculations to consider

Radius of Earth = 6.37 * 10^6 M, Therefore area of Eath cut down the centre and stuck in the sun = 1.28*10^14 M2

Area of Earth * solar intensity( 1kw per m2) *24Hr * 3600 seconds per hour = 1.10*10^22 Joules per day.

Assuming 2% of this energy is converted to biomass and 1/3 of the Earth is not under water , Thats 7.34 * 10^19 joules to play with.

Thats about 12238 MJ per person per day.

One value Ive recently heard for the energy practically able to be harnessed from a litre of hydrocabon fuel, (9.1 kilowatt hours ), equates to about 33 MJ. (I havent confirmed this yet)

So this theoretical maximum equates to about 371L of fuel per person per day.

Unfortunately most of this land is not vegetated at all, let alone growing plant matter at it's maximum rate ( actually only possible with energy consuming fertilizers and irrigation).

Lets assume 10% arrable land and plants growing at half their maximum rate. Thats now about 18.5L per person per day. These figures look better when you remember to convert 1 kw into 1000w, and get the correct radius for the Earth, but we are still in strife because this forgets we need to gather, process and distribute the fuel produced from this biomass. That would probably leave about 5L of fuel per person per day , even before we start building the machinery to do it with.

Now you see the problem with biofuel, hydrogen from solar, etc, THERE JUST IS NOT ENOUGH ENERGY COMMING IN TO REPLACE WHAT WE USE. The only option is to live within our means.

For even more bad news on how soon that time will come, look up stuff on "peak oil" and dispare if your satisfaction comes from anything reliant on fossil fuels.

(Please feel free to verify and correct these figures if you find any errors).

wow i didnt evan think about this issue and mybe that the problem people just dont think what harm we don by leaving a light on

thanks peeps i do plan to look into this more
mike.c

Boifuels and ultra eficient diesel engines are the solution here.

Vauxhall have built a VX220 with a 1.3L common rail diesel engine that has a top speed of 155MPH and a combined cycle fuel consumption of 113mpg. Engines like these obviously require much less fuel than standard engines (petrol returns a disgustingly small mpg). This means Biofuels become a real option. All we need to do is concentrate on producing high yield crops for oil (hemp is apparently particularly good) as well as recycling waste vegetation and used oils.

As a comparison - The best car on the road at the moment for fuel consumption is a 'Vauxhall (Opel / GM) Astra LS Eco4'. It averages 64mpg. I have a 1.9dci Renault Megane which is currently telling me that its doing 54.8mpg. An modern petrol car will do anything around the 40-45mpg mark, older ones (and Land Rover / SUV things) could be anything around the 20mpg mark.

As I said - reducing fuel consumtion greatly reduces the total amount of energy needed. This new diesel engine is almost twice as efficient as any before it - all cars could be run on a fraction of the fuel and energy that they currently do.

http://www.bnp.org.uk/peakoil/resources.htm
been looking into this peak oil and found this site by the bnp(i didnt vote for the its just a good site for peak oil info) thought other would like to read thought this...
mike.c

I dont think hydrogen cars would be so bad, the ammount of cars we have on the roads in world is creating enmormosue amounts of carbon green housegas (whatever the term) build up, now if you take into the consideration that even though hydroden needs to be made in the first place, your still taking milliosn of cars of the road that belch out crap everytime there driven anywhere. We still need to burn fossil fuels (mostly) to make the hydrogen in the first place, wich isnt perfect, but it still takes the cars off the road wich because of there numbers are doing way more harm to the enviroment to the lesser number of fossil ful power stations.

So hydrogen cars, are a very very good thing.

I think to be honest governments need to stop being soft and build more of those wind generator things, stop listneing to all the people complainging about ho it ruins the landscape to have them built, for god sakes when were all breathing black smoke and putting up with acid rain eating our buildings and trees, the landscapes not gonna be worth saving anymore.

They might not be very efficiant, but I think they look snazzy and if they can make up a little bit of the total energy we use, and mean we use less of the older power staions then there a good thing. Then theres this stuff ive heard about useing waves or something, now thats a clever idea, dunno how they work tho

If you are creating hydrogen out of water, wouldn't

1) the water need to be purifed down to H20, lest a bunch of salts / minerals, etc. all build up on equipment and such? And

2) The other product would be oxygen correct? Isn't pure oxygen highly flameable? So what happens if there is a spark and catches the oxygen on fire and plants start exploding?

I really have nothing to add... my head must be in a wierd place today if this is all I can come up with for this topic.

When they refer to hydrogen power cars, are they simply meaning burning hydrogen in an internal combustion engine, or do they also mean hydrogen cell cars, which produce electricity by doing something incredibly clever in a souped-up battery. I heard that the latter is more efficient than the ICE but you still have the general disadvantages of a battery - driven car.