Does it matter how hard you drive?

[John-Fram]

Not really.

 

First I tried but failed to paste in a chart of costs per mile v annual mileage for different mpg's. I have attempted to upload a pdf of it instead but apologies if a lack of user IQ means it has not worked.

 

Second, I have ignored any consideration of the impact on the planet and the environment in general, (which if that was truly important then we would not be wasting energy importing anything from the other side of the said planet).

 

Instead I have focussed on running costs per mile; not simply fuel economy. Granted the softer and more economically we drive then the less we will spend on fuel but that is just part of the overall cost. Also if we keep it in the garage and only drive 2 miles to the pub on a Sunday then we are not going to spend much on fuel compared with shampoo and wax.

 

This is of course based on my circumstances which includes £245 road tax and insurance for less than £300 - but the principles will hold firm. I have included interest on a loan/loss of interest if car sold and money invested, depreciation (£1000 for 10000 miles), road tax, insurance, RAC/AA etc, MOT, servicing, tyres (£500 for 18000 miles) then calculated the cost per mile for 20, 30 and 40mpg for annual mileages of 1000 to 20000 miles. I used £1.40/l.

 

I think at least for me 20 mpg is below the tolerance level of the passenger whereas 40 is beyond my wildest expectations.

 

If you spend more on tax, insurance, tyres then the following cost comparisons will be even tighter.

 

Conclusions?

I'm sad to analyse this. You are probably just as sad if you are still reading this.

 

Below around 2000 miles per year I might as well enjoy myself for 20 mpg at£1.09/mile compared with striving to achieve 40 mpg at 93p/mile.

 

For less than 3000 miles per year there is next to no difference between 30 and 40 mpg. Even at my annual mileage of 9000, there is only 5p difference per mile or less than £500 per year so there is little point in spending a large sum to achieve such a large improvement.

 

At 9500 miles, fuel begins to be > 50% of the overall cost for 20 mpg.

Amazingly I would have to do more than 50000 miles per year at 30 mpg before fuel began to approach 50% of the cost.

 

If I could achieve 40mpg then forget it, other running costs are always going to dominate.

 

So what? Well for me given I am not about to sell her because I love driving her so much then I am not going to invest in fuel saving mods nor worry if an occasional burst of enthusiasm takes me well below 30mpg. Fortunately my daily commute of 16 miles each way can be accomplished with minimal stops for 30 ish.

 

Nissan_350Z.pdf

[evest]

Interesting post mate. For me, she's a daily runner with 25miles each way so I need to be hitting the 30mpg mark too make things economical. Fortunately I have plenty of twisty A roads, so keeping it passively between 50-60 mph to achieve this still make for a reasonably drive. The main thing I have adjusted to is lighter pulling away and slowing down - has made a noticeable difference.