Sir – During the recent heatwave I think many shoppers have ‘enjoyed’ taking refuge in a supermarket, where it has been delightfully cool, so cool that the assistants are usually wearing fleeces while they work.

However this haven comes at a cost. Are we mad? The supermarkets have long aisles of cool cabinets open to the elements.

At home we would think it foolish in the extreme to leave our fridges open all day — a waste of money and of course energy. To be fair to the supermarkets, I can see the benefits of open fridges; ease of access for stacking and less congestion from doors opening and closing.

However, surely it is not beyond the wit of innovative technology to solve these problems. Also maybe we need to be prepared for a little more hassle in our shopping experience in order to save on our energy demands in and out of our homes.

Rosalind Fiennes, Clanfield