Sir – For some time I have argued that the simplest and most effective way of economising on electricity used for street-lighting is to switch off every other light permanently.

The exact percentage will vary in different locations, but major savings there would be.

As for motorways and dual carriageways — anyone who has driven at night past the High Wycombe junctions on the M40 or around the Oxford Ring Road at various locations, knows that, quite pointlessly, those roads are powerfully illuminated all night long when traffic is very light; and cars and lorries have much more efficient lights than hitherto. Another example of imaginative thinking required of the county council?

Mike Gotch, Wolvercote