points for hydrogen as an alternative fuel source?

Question

i am doing a presentation for my a level chemistry on hydrogen as an alternative fuel source, i have already researched it - but to see if there are any areas i missed if anyone wants to have a go and see what they come up with - maybe someone knows alot about this subject? - it will be much appreciated

these are the questions:

-suitability for use in road transport
-availability and cost of supply
-energy density (energy per gram)
-whether existing engine technology can be adapted
-ease of storage and distribution
-effect on environment
-safety in use


thanks alot

fed

Answer 1

It is suitable for use in road transport. There is however a need for quite large investment in infrastructure to provide retail outlets.

Hydrogen can be produced from natural gas, petroleum or coal by steam reforming (much more efficiently than by electrolysis of water). It is still likely to be significantly more expensive (at least before tax) than gasoline/diesel in the foreseeable future. The byproduct of steam reforming, carbon dioxide, needs to be sequestered (there are a number of potential ways in which this can be done - google search carbon sequestration - it is already being done into deep underground reservoirs in Algeria and the North Sea) to maintain a carbon neutral fuel.

The energy density per gram of hydrogen is very high, however the energy per unit volume may be lower than some other fuels even when stored cryogenically or under pressure. Thus there may be large and/or heavy fuel tanks taking into account also the need for cryogenic insulation or tanks with thick walls built to withstand pressure.

Engine technology can be adapted.

It is somewhat more difficult to store and distribute than conventional fuels.

Hydrogen burns with air producing water vapour and some polluting oxides of nitrogen.

Care needs to be taken in the selection of materials as hydrogen can embrittle metals. Hydrogen has some adverse properties in terms of fire and explosion hazards in that it has a very low energy of ignition and a very wide flammable range (although the lower flammability limit is similar to other hydrocarbon gases). However it is also very much lighter than air and in the open will disperse rapidly upwards unlike say petrol vapour which can creep across the ground. The advice may well be that hydrogen powered vehicles should not be kept in confined spaces (eg garages) in case there is a leak of hydrogen.

Answer 2

both would take a long time to get into common market. no way we can just up and say we are now a hydrogen society and build the hydrogen infrastructure over night. with oil we have at least 10 years before gas prices come down (if we drill and build new plants.) i think that we should be doing both as in about 30-40 years hydrogen cars and trucks will be common place among the current gas burning cars and in about 45-60 years we will be in hydrogen vehicles.

Answer 3

A lot of good points on here I think -sure you'll figure out which - maybe this is one...
I wonder in particular about the energy source used to extract hydrogen and platinum catalysts, and the magnitude and effects of emitted water vapour by a city full of H powered cars.

Answer 4

Hydrogen can be efficiently used in fuel-cells to produce electric, but fuel-cells need particular metals (different types give different environmental and supply issues)

Fuel cells or combustion produce water which IS a pollutant, Damp housing, especially the cheaper types by the side of main town roads, is a major cause of mould & disease.
Also imagine the impact around desert cities like Las Vegas; or even from east coast US on the north atlantic drift saline pump.

Home brew hydrogen in basements & garages will probably need to be outlawed & policed.

Hydrogen is very dificult to store & transport due to small molecuels that escape easily.

Hydrogen is only an energy transport mechanism, it currently needs electric or natural gas to produce.
Much more efficient on whole energy cycle is battery vehicles, and suitable technology is here today to meet all of our personal transport needs. We don't need to wait for 10 year subsidised research programmes to deliver quiet, smooth, smell free vehicles.

eg a Phoneix SUT that does 90mph 250 miles per charge, 10 minute recharge. http://66.218.37.153/news.htm;
or sports car that will out-perform a ferrari, made by Lotus in Norfolk UK (but not featured on any UK TV programme or magazine) http://www.teslamotors.com/index.php?js_enabled=1

So the other questions youo could ask is why are governments/global oil companies supporting Hydrogen research and ignoring a fuel available today at home or work.
And why the media totally fail to question the motoring establishment on their sustainability & environmental responsibility; eg why they crushed their electric vehicles, despite demand, www.whokilledtheelectriccar.com.

Answer 5

1- London has a few hydrogen-powered buses in use and I think that it's Iceland (the country) that has hydrogen pumps at their petrol stations
2-I don't know where they get it from, but I always assumed that they just electrolysed water.
3-no idea
4-it's a gas, so I doubt it's very heavy
5-the only product is water (but if it is produced by hydrolysis, then the pollution has already been caused in the power plants
6-didn't German blimps or something used to use them in the war? then one blew up and it caused a huge explosion?

oh well, probably not much help but good luck and stuff.

Answer 6

Important basic point.

Hydrogen is not an energy source. We can't mine it. It is a way of transporting energy from one place to another. Like transporting solar energy from Arizona to a car in Los Angeles.

Answer 7

reaction reversible ( meaning supply would never dry up, literally)

although i would not be so sure about safety. hydrogen is highly volatile.