DATELINE 1 APRIL, 2021: The Government is keen to nudge people to choose more energy-efficient household appliances and for many years has helped consumers by getting manufacturers to put energy labels on products, typically rating them A to G to signify that they are more or less energy efficient (a concept too complex for most people to grasp). And for people who find the concept of A, B, C etc too complex to grasp they add coloured arrows of different lengths. The shorter the arrow, the higher the efficiency.

The march of progress has caused problems because many products are now more energy efficient than the bureaucrats foresaw. They are crowded into the ‘A’ rating band, and unfortunately there are no letters before A in the alphabet so ‘A’ is now sometimes subdivided into A+, A++ and A+++. However, most people find this concept too difficult to grasp, so the efficiency scales for affected appliances will be regraded A to G so that for example what was A++ will now become B, A will become D, and so on (they will take F off).

Meanwhile a rival scheme for washer-dryers caught my attention. This gives a three-letter rating signifying the efficiencies of washing, spinning, and tumble-drying parts of the cycle. Thus a machine that is in the most efficient category in every respect gets an ‘AAA’ rating. With a bit of forethought they could have started later in the alphabet to allow room for future improvement. They could even have helped people by using the sequences W to Z for Washing, S to V for Spinning, and D to G for Drying. Then a machine currently labelled ‘ABC’ would become ‘WTF’.