Maybe petrol stations need to diversify - like selling hydrogen - which Toyota at least see as the future.
It sounds very tempting, doesn't it, to replace petrol with hydrogen, just fill up with hydrogen like we do with petrol, and back on the road again. No range anxiety or having to find a charging point that works to recharge your electric car. But there's rather more to it than filling your tank with petrol. The hydrogen would be at high pressure compression at service stations, typical pressure levels are 3 - 4 MPa (Megapascal) for pre-compression stages for filling of collecting tanks, and 25 - 30 MPa for storage tanks in fast-fill applications.
1 MPa = 145 PSI, so 30MPa = 4,350PSI).
Presently, the only benefit of using hydrogen to power cars would be to reduce inner city pollution, because when hydrogen is burnt in a car engine it combines with oxygen to produce only H2O (water vapour) at the tail pipe, clouds form, rain falls and the water cycle is complete. But Hydrogen is only found in nature in compound form, so it must first be produced through the use of a primary energy source, before hydrogen itself becomes available as a secondary energy source, and that's anything but 'environmentally friendly'.
Primary and secondary energy sources for hydrogen production:
The primary energy source presently used in hydrogen production is from fossil fuels via natural gas reforming as well as the partial oxidation of heavy fuel oil (or Diesel) and coal. Other processes are in the research and development phases, perhaps the most promising of which is the gasification of biomass, but there is the possibility of direct production of hydrogen from algae subjected to solar radiation.
However, it isn’t what is
technically possible, but what is
commercially feasible that matters. Presently, only the biomass gasification process is likely to come to the market as a competitive product within the next few years. Electricity is presently the only energy source used to produce hydrogen, either by the electrolysis of water or as a by-product resulting from the chlorine-alkaline electrolysis.
Water electrolysis is independent of primary energy use and as such is seen as the essential element of a hydrogen-based energy sector. As another secondary energy based production method, the reforming of methanol in mobile applications could play a role in the near future.
Production from fossil fuels:
Of the approximately 500 Bil. Nm3 of hydrogen traded worldwide, the vast majority originates from fossil fuel sources (natural gas, oil) as a by-product in the chemical industry during the manufacture of PVC (e.g. chlorine-alkaline electrolysis) or from crude oil refining processes. All in all, the production of hydrogen as by-product accounts for 190 Bil. Nm3 worldwide (38%), of which about 2% or 10 Bil. Nm3 stems from chlorine-alkaline electrolysis (or in Germany, 4.5% of the total 19 Bil. Nm3 of hydrogen produced there).
Production from electricity by means of electrolysis:
Of the various procedures to produce hydrogen from water, electrolysis is presently, and for the foreseeable future, the only one of practical importance. Water electrolysis in its conventional form, alkaline electrolysis, has been in commercial use for over 80 years.
Up until the end of the eighties, only a small and declining portion of approximately 0,5 - 1 Bil. Nm3/a that is 0,1-0,2% of the world production of hydrogen, was directly produced by electrolysis, mainly in connection with hydro power. Even this small quantity is declining since the electrolytic production of hydrogen for fertilizer manufacture is no longer competitive with production from natural gas due to falling energy prices.
Because electrolytically produced hydrogen is created indirectly via the energy carrier 'electricity', this process is only economically feasible in places where electricity can be extremely cheaply generated. This is generally only possible with large scale hydro systems (Egypt, Brazil, Iceland, Canada, Norway, Zaire), or with excess energy from the primary and secondary control of existing power station capacity with significant nuclear component (France, Belgium, Switzerland, some German Electric Utilities).
Storage and transportation of hydrogen:
Depending on the desired use, hydrogen must be either compressed or liquefied. Compression of hydrogen is carried out in the same way as for natural gas. It is sometimes even possible to use the same compressors, as long as the appropriate gaskets (e.g. Teflon) are used and provided the compressed gas can be guaranteed to be oil free.
Since hydrogen compression is carried out in the same way as compression of natural gas, the procedure is well tested and readily available. New developments are mainly associated with the optimisation of the individual units within the total concept, with the primary application here being the high pressure compression at service stations. Typical pressure levels are 3 - 4 MPa (Megapascal) for pre-compression stages for filling of collecting tanks, and 25 - 30 MPa for storage tanks in fast fill applications.
1 MPa = 145 PSI, so 30MPa = 4,350PSI). The fast fill process is achieved by an over pressure over the pressure level in the vehicle tank being filled (20 or even 25 MPa). The choice of the highest pressure level is primarily dependent on the maximum permitted pressure that the storage tank can withstand (modern tanks constructed from composite materials are rated for up to 30 MPa). Because of the logarithmic relationship between pressure and work required for compression, the increased energy required for a higher filling pressure is not that great. Thus the compression from 0.1 to 30 MPa needs only 10% more energy than the compression from 0.1 to 20 MPa.
Environmental impact
As of 2020, most hydrogen is produced from fossil fuels, resulting in carbon dioxide emissions. This is often referred to as
grey hydrogen when emissions are released to the atmosphere, and
blue hydrogen when emissions are captured through carbon capture and storage (CCS). Blue hydrogen has been estimated to have
a carbon footprint 20% greater than burning gas or coal for heat and
60% greater when compared to burning diesel for heat.
Hydrogen produced from renewable energy sources is often referred to as green hydrogen. There are two practical ways of producing hydrogen from renewable energy sources. One is to use power to gas, in which electric power is used to produce hydrogen from power to gas, and the other is to use landfill gas to produce hydrogen in a steam reformer. Hydrogen produced from nuclear energy via electrolysis is sometimes viewed as a subset of
green hydrogen, but can also be referred to as
pink hydrogen.
So yes, you can power cars with hydrogen, but as things stand, at much higher cost and greater adverse environmental impact then petrol or diesel.
I've attached a paper which goes into more detail for anyone who might be interested.
The bell curve shifts imperceptibly to the left and the advent of job destruction courtesy of AI & automation will tend to exacerbate this (as what do people do when not working...) Global redistribution of dispossessed and economically deprived people, accelerated by climate change, may accelerate this resulting in humanity becoming equally coloured and less intellectually capable as a generality will have interesting results beyond our lifetimes. The gulf between the haves and have nots may well widen.
