There has been a significant boost to the hydrogen option as a means of tackling climate change with a recent debate in the Welsh Assembly about how the sector can be helped to grow.

A new trade association has also been launched in Cardiff to represent and advance the Welsh hydrogen economy.

Hydrogen is seen as a promising, clean alternative to using fossil fuels for heating and transport in particular and two Monmouth-based professors explained why they favour the option in a feature in the Beacon (January 15 ) - one of the month’s ’most read’ online articles.

Some of the points made were discussed in a letter from Bob Handley, particularly concerning the origin of the hydrogen and what he saw as the inefficiencies inherent in its deployment.

Mr Handley, who said he had 50 years’ experience in the energy business, pointed out that currently the vast majority of hydrogen is manufactured from methane (natural gas) and CO2 is emitted as a by-product. He claims that hydrogen manufactured in this way provides no benefit in reducing CO2 emissions compared to using natural gas in our home boilers and while it was technically possible to store the CO2 underground, this was currently an expensive and controversial process, though it may provide ’a solution in the future’.

The alternative of producing hydrogen by electrolysis was extremely inefficient, he said, adding that ’we would need to generate three to four times as much electricity to drive on hydrogen as we do to drive on BEVs’. He argued that charging overnight or at home was ’a realistic option’ for most residents in Monmouth, and the network of charging points was ’adequate for the vehicles currently available’.

Professors Averil Macdonald and Alun Vaughan were keen to address his arguments, pointing out that there had been some key advances in the technology in recent years - and it’s no longer just a matter of efficiency. Business as usual isn’t an option and the economic and environmental aspects have to he dialled in.

Firstly, charging battery vehicles at home was possible for only one in five households nationally with off-street parking, they said, and calculations show that the UK can only convert to about 10 per cent of vehicles being battery powered, so it won’t make a huge difference to emissions overall.

’’And how would you feel if you arrived home late and someone else was using the only available charging point - or if you were away from home and were forced to spend half an hour recharging in a dark, deserted car park?

"By comparison, filling your car with hydrogen takes only a few minutes at a well-lit filling station just as we do with petrol today.

"Shell has built a solar powered electrolysis station (to split water into hydrogen and oxygen) on the forecourt of a petrol filling station in Germany. They can make hydrogen on-site from ’free’ solar power and sell it direct to owners of hydrogen cars."

Prof Macdonald added that both Germany and Japan are installing national networks of hydrogen filling stations - ’and there’s already a hydrogen filling point in Abergavenny’.

She agreed that savings on electric charging were real - at the moment. But will this situation remain once the government needs to recoup the tax income lost in the move away from petrol and diesel?

"Hydrogen can, indeed, be made from decarbonising methane (natural gas) but the latest science allows the carbon to be bound into ’carbonates’ which basically resemble house bricks.

"We can create hydrogen, capture the carbon and use it to build much needed houses - we don’t need to bury CO2 underground."

She said that generating hydrogen by electrolysis is the perfect way to store ’spare’ green energy. If wind farms generate electricity overnight, at the moment it cannot be used. If we use this green electricity to create hydrogen, then it’s exceptionally efficient.

The Professors point out that the real message is that there is no ’silver bullet’ for reducing our carbon footprint. While rechargeable electric vehicles are a sensible option for some, hydrogen has to be part of the bigger picture, particularly when battery powered HGVs are a non-starter as they are far too heavy.

"The UK produces one third of our carbon emissions from our central heating. If we want to convert to zero carbon heating we could ’go electric’ but that means installing new electric central heating systems in 23 million houses - and that means replacing whole central heating systems at the rate of one house every 44 seconds if we are to be finished by 2050!

"A better option would be to convert all those gas boilers and hobs to burn clean hydrogen in exactly the same way as we converted everyone from town gas to natural gas back in the 1960s."

Prof Macdonald said plans are already afoot to convert Leeds to hydrogen by 2023.

"The UK is (almost) unique in Europe in having an extensive underground gas pipe network. This means we can re-purpose our gas grid and use it to carry totally clean hydrogen, generated by decarbonising natural gas or by electrolysing water using ’spare’ green electricity, and use hydrogen for zero carbon transport and zero carbon heating and cooking, We don’t need to transport any hydrogen around the country to filling stations as we transport liquid fuels today - we just send the hydrogen along the old gas pipes" she added.

Profs Macdonald and Vaughan are happy to give talks for local groups or schools. For further info see www.ready4ecars.southampton.ac.uk or contact [email protected]