CATRIONA Stewart ("Rebellion has far to travel if it is to become a common cause", The Herald, April 19) doubts that the Extinction Rebellion message on climate change will sufficiently shift the public’s attitude to this topic to influence government policy. But her reason for believing this seems spurious.

There is probably some justification for her claim that the public is fascinated by "big" human-inspired artefacts, but her example of a crowd of spectators at Glasgow Airport enjoying "gazing at a gas-guzzling plane" emphasises the feature of the aircraft possibly of least interest to the crowd and hardly makes her case. I would venture to suggest that a "clean" aircraft of similar size powered by electric-motor-driven, large-diameter turbofan engines would equally enthuse such a crowd.

Technology advances will not cease with the passing of the fossil fuel era, as we are already seeing with the preliminary electrification of land transport. Needless to say, aircraft of a type likely to be of interest to commercial airlines are more difficult to operate in a fossil-free mode, but not impossible. The aeronautics industries in Europe and the United States are already designing and prototyping such aircraft powered by turbofan engines incorporating motor/generator sets which achieve the requisite energy densities by employing high-temperature superconducting technology and advanced cryogenic cooling techniques. Reports suggest that initial models will probably be hybrids employing compact, highly-efficient conventional jet engines to drive the generators. However, later versions are likely to abandon fossil fuels as the primary energy source for hydrogen fuel cells or perhaps for high-density electrical energy storage systems. Such developments, of course, presume mankind manages to ensure that the planet has a human friendly future by abandoning fossil fuels, and this in turn means ditching the myth that "green" equates to primitive lifestyles.

In any case, it is possibly not too fanciful to suggest that in the foreseeable future Ms Stewart may well be joining a crowd of enthusiasts to see an all-electric airliner land at Glasgow Airport.

Alan J Sangster,

37 Craigmount Terrace, Edinburgh.

IT'S no wonder Ian Forrest sounds so upbeat in his electric vehicle (EV) letter (April 19)). After all, he's had two free charging points fitted at his home, and two lots of the £4,500 subsidy per car. That totals around £11,000 he's received from other taxpayers. Does he imagine that every single motorist in the UK could receive that subsidy? This is just yet another way of transferring wealth from less well-off people to more well-off people.

If Mr Forrest imagines that EVs are saving the planet then he should acquaint himself with the fact that in the big growth countries China, India, Indonesia, Australia and South Africa, between 58 per cent and 87 per cent of electricity comes from burning coal, so in these countries at least, EVs are essentially coal-powered.

Geoff Moore,

Braeface Park, Alness.

THE multiple drawbacks of electric vehicles (EVs) are well known: short range, charging, battery fire risks and very high costs to buyer and taxpayer.

However, the essential problem is that they don't "do what it says on the tin" and are, arguably, unnecessary.

Ian Forrest reports favourable experiences with EVs, "free" electricity from publicly-subsidised chargers, defrosting and warmth on cold days, engines with good, silent performance.

However, EVs' purported "green" benefits, less CO2 and "dirty" emissions, are negated when manufacturing processes are recalled. These cost scarce cobalt, from filthy, dangerous mining. The UK's negligible greenhouse gases,1.3 per cent of global, makes practical benefits to the global climate illusory.

The subsidies are not justified: EVs are very costly non-solutions to non-problems.

(Dr) Charles Wardrop,

111 Viewlands Road West, Perth.

YOUR correspondents urging us to support the Climate Change protestors (Letters, April 20) should consider advising Extinction Rebellion supporters to park themselves in Beijing. There, they would be unlikely to find themselves dancing and skateboarding with the police, if stories circulating from London are true.

A quick reference to Google reveals that the countries at the top of the CO2 emissions table are China, United States of America, India and Russia. The UK are 15th, with emissions of 0.04 per cent of those of China. Emissions by the UK have fallen for six successive years. In China, they are rising.

David Miller,

80 Prestonfield, Milngavie.