The great diesel experiment

We've all seen the price of petrol and diesel creep up recently. If like me you need your car to get to work, then spending £50 to fill up your tank every 2 weeks is enough to make you weep.

Over the past few months I have been conducting my own highly scientific experiment aimed at discovering the most efficient way of expending my diesel. I would recommend you undertake the same experiment - you will be amazed. (The experiment requires your car to be able to display the Miles per Gallon statistics)

Control stage

With a full tank of diesel I reset the trip computer so that the miles per gallon (MPG) was blank and ready to go. Then I drove around as normal. By normal I mean that I drove observing the speed limits of 30mph in town, 60mph on single carriage roads and 70mph on the motorways. My drive to work consists of 15% town driving, 50% single carriage A roads and 35% Motorway. I would accelerate away from and brake at junctions normally.

My tank of fuel lasted for 11 trips to and from work, at an average of 54.6 Miles to the Gallon.

Experimental stage

Again, with a full tank of diesel I reset the trip computer. This time I really tried hard to drive ultra smoothly. At junctions I would accelerate fairly slowly, trying to keep my revs as low as possible. Coming up to junctions I would try and anticipate them in advance, allowing the car to slow down naturally, rather than driving along at 30 and then braking at the last minute.

On the A roads I would try and do the same, keeping a long distance between me and the car in front. This meant that if they braked I could slow down gradually. Also I kept my speed down to a maximum of 50mph.

On the Motorways I reduced my speed to maximum of 60mph. This seemed really slow at first, but I soon got used to it and realised that loads of people drive like this. Lorries are only allowed to go at 60 so you are happily in the flow of traffic. I find myself regularly driving at about 57 or 58, and my revs never go very high.

Result? My miles per gallon shot up from 54.6 to 69.7 and my tank lasted an extra 3 days.

But surely your trip takes much longer?, I hear you ask. Strangely enough, not really. You can bat down the motorway at 80 and then the lights in town turn red and your 2 minutes of advantage is lost. You feel like you are going faster, but the actual difference in time is hardly anything at all. We've all noticed the boy racer types who zoom off at traffic lights only to have to brake suddenly at the next set while we pull up gently beside them. They have made alot of noise but saved no time and expended twice as much fuel. It's the same principle but over longer distances and time frames.

An added advantage is that I am convinced it make me a safer driver. Aside from the speeding issue (an offence of which I have been caught on camera twice in the past and have no desire to rack any more penalty points on my license) simple things like increasing the distance between vehicles on the road has got to be a good thing.

If you try this yourself, tell me how you get on.