Stop the hot air over wind-generated energy issues

Sir, – Much has been made by several contributors regarding the lack of wind-generated energy during calm days, the implication being that everything will stop. No TV, no radio, no anything electrical, cars included. This is a very simplistic view, but it suits their argument against electric vehicles (EVS) and climate change initiatives

Pumped water storage as in hydro-electric systems has been used for many decades to provide this energy gap-filling role – typically, the TV advert breaks when the kettle is switched on for a cuppa.

Static battery storage – both lithium–ion (l-ion) and the newer sodium-sulphur (NAS) – is being developed and deployed, having been known and around for at least two decades.

Gravitricity is a new entrant to provide energy when wind cannot cope with demand. As excess energy is produced, a very heavy weight is hoisted up a shaft. When the energy is next required the weight is lowered, generating the energy required.

On reading the explanatory literature, these very heavy weights of 12,000 tons need to be housed in underground shafts 1,000 metres deep, like mines.

This system on initial reporting seems to have the lowest cost of storage per megawatt-hour, when compared to others in the field. There appears no long lasting toxic residue and it can operate at both slow and fast-paced energy delivery.

Another contributor to these letter pages advises that tidal power can be used to provide a reliable energy source, and should be supported as another energy delivery system.

Reducing the use of energy, by insulation and other agreed methods is also a key direction that we should all use. Switching off “vampire devices”, those that consume power, also helps. That wee, red led hides a hungrier energy pack of electronics just waiting for the remote button being pressed or your voice saying “Alexa”.

So yes, currently, Scotland and the UK do not yet possess the full coverage of low wind days, but I am confident that this gap will be closed. Alistair Ballantyne. Birkhill,

Angus.