AS a retired research scientist from the energy sector, I was astonished to read the article by Neil Mackay upon the proposed development of hydrogen as a “green” fuel (“The key to health and wealth? Bottled sunshine and wind”, The Herald, March 26).

Hydrogen does not occur naturally. Every molecule has to be manufactured and electrolysis is the proposed process.

This process converts about 80 per cent of the energy used, into gaseous hydrogen.

When this gas is used, further efficiency losses are inevitable. More energy must be generated by other means to manufacture hydrogen than can be recovered in its use. This is not even a decent lunch, let alone a free one.

Natural gas methane, which as a fuel the hydrogen would largely supplant, occurs naturally and yields a very great more energy in its use than in its extraction.

The energy content, litre for litre, of hydrogen is only one-third of that of methane.

This implies that supply lines have to be three times the area of the present natural gas, at present pressures, or at three times the pressure. At present, bulk-line pressure is 50 bar, 750 psi. Tripling this is not to be contemplated.

The glib suggestion that hydrogen may be transported as ammonia totally overlooks the energy requirements of the process to convert hydrogen to ammonia. The suggestion is folly.

The storage of hydrogen is difficult and the tiny molecule escapes very easily.

Specialised materials are required for components handling the gas. The explosive limits are extremely wide.

The suggestion that a major industry may be founded on hydrogen is fallacious.

But the political arena is populated by those making hugely important technical decisions, which they are entirely unqualified to consider.

Few, if any, persons, at ministerial level in the United Kingdom have made graduate studies in engineering or the physical sciences and will have abandoned these subjects at an early stage in their careers.

Those in political office take advice, seemingly, only from lobby sources, whose interests lie solely in promoting policies with financial benefit to themselves.

Richard Phillips,

Four Winds,

Wickham Heath,

Newbury,

Berkshire.

IT is particularly gratifying to stick your neck out on a topic, risk being labelled a crank but then to be vindicated when someone in the mainstream press backs up your argument.

The Herald has published two of my letters regarding hydrogen as a fuel of the future. Some readers may have thought I was on another planet.

So it was particularly pleasing to read Neil Mackay’s article in your newspaper this earlier week that made an even more persuasive argument in favour of this renewable, CO2 friendly fuel.

He is absolutely correct in his assessment. that Scotland is sitting on the edge of another energy boom the like of which we saw with North Sea oil.

However, now is the time for politicians to embrace the potential of this fuel of the future.

I have written to politicians regarding embracing a hydrogen economy. To my great disappointment, I have not received a reply.

It is incumbent on independence supporting political parties urgently to look at what could be our next North-Sea-oil boom.

The volatility of the oil industry and our dependence on it contributed to the fear factor for many swithering voters during the independence referendum in 2014.

The opportunity to right the wrongs of previous Westminster governments that appropriated oil revenues only to squander them is presenting itself.

An independent Scotland could substantially fund itself from a hydrogen economy and provide a Norway-type fund.

And this time there would be no arguments over territorial waters and the ownership of the reserves therein.

It would be Scotland’s hydrogen. There would be no argument about that. It could be just the game changer that a second independence referendum campaign needs.

William Thomson,

25 Lithgow Place,

Denny.