The Climate Emergency is finally making itself felt – and there will be worse and more frequent catastrophes in the future. However the UK government’s “net-zero” aviation strategy – first so called in 2021 – has yet to take off. Widely described as a “pie in the sky”, it depends on almost unavailable and grossly unsustainable alternative fuels in the immediate future and vast supplies of hydrogen to fuel yet-to-be-developed propulsions systems later on.
The last time a technically ignorant and cloth-eared UK government tried to foist hydrogen technology onto aviation it led to the tragic of the loss of the airship R101 on its maiden flight to India in 1930. It got no further than Northern France and burst into flames and crashed with only 6 survivors out of the 54 on board. The Air Minister at the time, a number of senior government officials and most of the design team were among the fatalities. The German Nazi government followed up in 1937 with its own disaster, with 36 people killed. Although their airship, the “Hindenburg”, successfully crossed the Atlantic only to catch fire on arriving in New Jersey.
A common factor was that both governments were trying to rush the completion of prestige projects without sufficient technological understanding by the decision makers.
The UK government re-announced its “Jet Zero Strategy” on 19th July 2022, with a target of cutting carbon dioxide emissions from civil aircraft to net zero by 2050. This depends on the usual mix of mitigation, “green fuel” and magic technology. The mitigation includes the planting of trees somewhere – but will they now survive in the higher temperatures? – the extraction of CO from the atmosphere – but money, energy and repositories are needed to do that – and of course the famous hydrogen and its associated technology.
Hydrogen is currently produced from natural gas just as it has been for a century or so in the water-gas process – but this produces a great deal of CO as well. It can also be produced by electrolysis of water using surplus electricity from solar panels or from wind turbines, but this is not a very efficient process and the hydrogen is difficult and expensive to compress and store. It can even slowly diffuse through stainless steel. A hydrogen fuel, precisely because it does not produce carbon dioxide, would not perform well in either a jet engine, a turbine or an internal combustion engine. It could, if highly purified, be used to produce more electricity via a fuel cell, but this would then need an electric motor to power a propellor.
Although the production of hydrogen from surplus wind or solar energy, despite the inefficiency of the process, is sensible, the most economic subsequent use of the hydrogen would be as an additive into the natural gas network (up to 20%) over the next 10 years or so.
Not only is the condensation trail heating effect of aviation even greater than the greenhouse gas heating effect of its CO emissions, but also it is often neglected in calculation the atmospheric damage of aviation. When correctly calculated, this is truly enormous.
Then there is also the additional disturbance to atmospheric gas chemistry caused by NO emissions.
Altogether, aviation now has to be viewed as a highly damaging and polluting form of travel. Aviation will have to be significantly reduced – and quickly. It is hopeless trying to pretend, as the UK government is doing, that we can carry on not only with the present number of flights, but with the current increasing trend being maintained. It is unviable under any circumstances.
It was good to have air travel accessible to the many – unlike 40 years ago when it was only for the wealthy few – and it enabled people to enjoy long distance travel to exotic locations for holidays. But now we are more aware of the dangers of uncontrolled climate change and know we have to make drastic changes to our lifestyles and behaviour.
Air travel is subsidised by nearly every government in the world – insofar as aviation fuel is untaxed nearly everywhere, while fuel for other modes of transport usually is not. This will have to change.
For a start…
Let’s put a small tax on aviation fuel to incentivise
* fuel economy,
* reducing in greenhouse gas emission and
* cutting out air pollution from unburned fuel
The revenue could then be used to offset public transport costs and encourage a shift from inefficient private cars to trains and buses.
Measures taken elsewhere have been
* cutting out short haul or domestic flights
* serious cuts to train fares
* air ticket taxes
* reintroductions of long-distance overnight sleeper trains
In the medium term we must reduce the number of flights to and from the UK drastically, abandon airport expansion plans and close down or mothball some of the little used provincial airports.
Ground the planes to save the Earth!