Going Nowhere Fast

The government announced last week (for about the third or forth time) that they are going to investigate raising the motorway speed limit to 80mph. I suspect that this is mainly a populist nod to the nation's Audi owners and has nothing to do with "generating economic benefits of hundreds of millions of pounds through shorter journey times".  However, I think the exercise is a complete waste of time.

On the face of it, it sounds great, but how much difference does it make. On occasion, I drive from Central Scotland to North West England. It's quite a long journey so you would think a faster speed limit would be a big time saving. However, a sustained 80mph would only be reasonably possible between Motherwell and Preston - either side of this is far too congested. Still, this is a distance of around 170 miles so one would think it should make a big difference in journey times compared to driving at 70mph. In fact, it would save me 18 minutes - about the same time wasted by a typical roadworks. So does driving fast ever significantly reduce journey times? Well, it can do.

We have driven through Germany numerous times and there are still sections of their motorways which are unrestricted - in theory you could drive as fast as you like. I don't. First of all, driving very fast is remarkably stressful - traffic can change rapidly and the slightest imperfection in the road can make steering very sensitive. Then there is the fuel consumption - driving very fast makes fuel consumption figures go down the toilet. It may just be a family hatchback but you would end up with mpg figures which would make a Jaguar blush - and you don't even get the comfort of a Jaguar, or the acceleration of a Jaguar, or the quietness of a Jaguar, or even the general Jaginess of a Jaguar. Of course, if you were to drive very fast in a Jaguar you would end up with the fuel consumption of a Chieftain tank. On a couple of occasions we have driven very fast for sustained periods but this has been because we were late for a ferry. It is possible to haul back an hour or so journey time but it isn't fun or exhilarating. In fact, this also shows up the other downside of high speed motoring - it shreds tyres. After one ferry dash I had to replace the front set of (what had been ) fairly new Michelins.

To be perfectly honest, there isn't much to be gained by driving at 70 over 60mph. To travel from my house to Manchester at 60mph compared to 70 is only half an hour longer and the saving on fuel can be quite considerable: The wind resistance at the higher speed increases by about a third and this has to be paid for at the fuel pump. As it is, I tend not to travel at 60 but this isn't so much because of time considerations, rather that I actually get quite bored and overtake the odd HGV for amusement's sake. However, I can remember travelling down to South Wales during the fuel blockade of 2000. Few cars were on the road and most of those were travelling at 50mph and under - including myself. I managed to get an average fuel consumption on that journey of around 60mpg in a car that was officially measured at under 40mpg. I still managed to make the journey in reasonable time and probably saved around £15 in the process.

Actually, I am wondering if there is another reason for the proposal to raise the speed limit. The economic downturn combined with high fuel prices means that we are, as a nation, using significantly less fuel. TheAA estimate that this costs the exchequer over £1 billion per year in fuel duty. A faster speed limit may just raise that figure by increasing fuel consumption. Of course, it may also increase the number of severe accidents on the motorway network which will cause everyone to be delayed. Then everyone will be going nowhere fast.