clunk-click, every trip
A while ago I commented on how I thought hydrogen, contrary to the world’s dash to battery-based EVs (electronic vehicles), was worthy of note – http://carlbeetham.com/carmageddon/ – and was steadily creeping-up in the blind-spot of the automotive industry. I even poured scorn on the two long-standing quips that ‘fuel cells were no more than fool cells’ and ‘hydrogen is the fuel of the future…and always will be!’ Boom-boom. So, a little further down the road, where are we now at?
Cards on the table, notwithstanding our increasingly precarious fuel and energy situation, not a great deal seems to have changed wrt transport and hydrogen fuelling. However, now that governments are faced with almost certainly having to put hydrogen infrastructure in place to decarbonise residential heating and industrial production, this makes an integrated national system far more likely. On its jack-jones hydrogen infrastructure for transport proved itself prohibitively expensive.
Everyone can see that as it contains no carbon and hence, produces zero CO2 and almost no NOx, hydrogen is inherently a good thing and represents the simplest of all e-fuels. Sounds ace and what’s not to love? Furthermore, the redevelopment of our combustion engines to accommodate hydrogen fuel appears comparatively simple. The apparent logistical issues, relative to all the tech details concerning combustion and flammability, do seem a little mundane: materials and storage.
With petrol and diesel we’re used to liquid fuels and the fact that they can be simply and easily placed within low-cost plastic-moulded tanks. Not so gases, of which hydrogen obviously is. In order to get a decent amount in hydrogen into a vehicle, which in turn facilitates an acceptable distance of travel, storage pressure needs to be in the region of 10,000psi. Think of your tyres being at around 32psi and you’ll get the idea. This isn’t beyond the wit of man, as evidenced by the previous less-pressurised use of liquid petroleum gas (LPG) but, with strengthened and braced carbon fibre tanks, it ain’t gonna be cheap and they ain’t gonna be small. Consequently, forget hydrogen as a fuel for tiny ‘city’ cars, scooters and motorcycles.
And then there’s the materials issue. Being the smallest molecule, it transpires that hydrogen, even when it’s actually in the tank, doesn’t want to stay there! It quickly leaks through metal and plastic and eventually escapes from carbon. Not particularly helpful. Ironically, those hydrogen Zeppelin engineers of old discovered that ‘goldbeater’s skin’ did a half-decent job of keeping hydrogen in place. For those of us unfamiliar with ‘goldbeater’s skin’ it’s made from cattle intestines of all things. For good or bad, we’ve now moved onto synthetic polymers and the green lobby are unlikely to support such a widespread initiative.
In summary then, the future of hydrogen fuel remains as undecided as it did several years ago, which is a great shame. However, as long as the jury remains out our combustion engine love-affair soldiers on.
