WILLIAM Thomson (Letters, May 19) fears that the UK is "backing the Betamax horse" in encouraging the rapid adoption of battery electric vehicles instead of hydrogen. I don’t think this is at all the case; I’m sure that there is a strong future for both technologies, but I’m in no doubt that batteries will be the primary source of energy for most cars and small vehicles during the next 30 years or more.

The "huge gaps in recharging infrastructure" are overstated; electric vehicles (EVs) can be charged from anywhere with an electrical socket, and we aren’t short of those. Most EV owners use a home wallbox for a slightly faster charge (typically four to seven hours). This is hugely convenient and in the two years and 25,000 miles I’ve had my EV for, I’ve never had to wait for it to finish charging at home, so charge times simply aren’t an issue – it just fuels up on a cheap tariff whilst I sleep. By comparison, it’s very unlikely that hydrogen fuelling systems will ever be affordable or compact enough to install at home, meaning you will always have to go out of your way to fill them up.

By energy used, more than 98 per cent of my charging is done at home, which is fairly typical for EV users. That doesn’t mean we don’t need a reliable and widespread public charging network; at the moment this is growing roughly at pace with the number of EVs on the road, although more could always be done. There are advantages here for batteries over hydrogen; a rapid charger has a footprint of only a couple of square metres, fitting comfortably at the end of a parking bay, and typically costs around £30-50k at present. By comparison, most hydrogen fuelling stations are still the size of a shipping container at best, and will cost many hundreds of thousands, if not millions of pounds. Pound for pound in terms of investment, this means it is far easier to create a widespread public EV charging network than a hydrogen one.

The principle reason that hydrogen is unlikely to become such a widespread fuel for cars is cost; not only are hydrogen vehicles generally more expensive than EVs to purchase, the round-trip efficiency of hydrogen vehicles is far lower – often around 30 per cent after the electricity is used for electrolysis to generate hydrogen, more energy used for compression, and then further losses encountered in the fuel cell when the hydrogen is used to generate electricity in the car. By comparison, most EVs have a round-trip efficiency of 85% or more.

It is vital that the UK and Scottish Governments continue to invest in the hydrogen economy, which is likely to be very important for larger vehicles like HGVs and ships, with advanced plans for these in the Western Isles and Orkney already. However, most governments (and most car manufacturers) worldwide recognise that batteries are here to stay and represent the best chance by far to rapidly decarbonise the cars and vans on our roads.

Jamie Adam, Balbeggie, Perthshire.

I STRONGLY agree with William Thomson regarding hydrogen to fuel our transport. Electric vehicles require lithium for the batteries. In the countries where this is found, it's the same story as the oil-rich countries,;it causes the same environmental pollution accessing the lithium. The people who are employed by rich industrialists and governments to get the lithium out are paid more than the usual agricultural work, but the damage to the planet and the workers by greedy industrialists is just as bad as the oil industry.

The answer to transport needs does not lie in lithium batteries, unless we want to replace one pollutant with another. And that will not leave future generations the legacy they deserve.

Margaret Forbes, Kilmacolm.