Yes I’m glad you pointed out the shortcomings of my analysis, rojash. (As I said in the original question, it was very rough and ready).
But for the purposes of this question, six times as many deaths occur per mile of motorway than they do per mile of other roads. The density of the traffic on motorways is an even stronger reason to maintain lighting (where it is provided) during all the hours of darkness. After all, that’s what they were provided for.
The government has no proper game plan when it comes to reducing carbon emissions. I heard the preposterous Mr Huhne (Her Majesty’s Secretary for Energy and “Climate Change”) on Radio Four this morning. He was asked about the likelihood of further steep increases in energy prices. All he could do, instead of answering the question, was to prattle on about householders getting their lofts insulated (which most people have done anyway) and to emphasise how important his useless and ridiculously expensive windmills are to the government’s energy policy.
If the government is really intent on reducing carbon emissions a far more effective way to do so would be to prevent shops from throwing open their doors in the middle of January and then heating the street up nicely for ten or twelve hours a day with their 25Kw “curtain” heaters. The savings made by turning a few lights off for a few hours each night would pale into insignificance alongside this simple but far more effective (and potentially less damaging) measure.
Turning street lights off at night (particularly on motorways) is a ridiculous notion – almost as ridiculous as Mr Huhne’s useless windmills.