What uses more fuel? A 5 mile 20 minute journey, or a 15 mile 20 minute journey?

fivetide

berbastrike wrote: »

I wasn't conducting a scientific experiment just a guide, stop being so fussy!

Only checking! The maths just didn't work that's all. You might have been looking for a specific reason.

I think it is clear that with the time involved the short journey will use less fuel but your mpg will actually be lower.

Changes to the time/distance will see the longer journey become more fuel efficient I would have thought.

There is probably a point where the two break even if you factored in all the variables.

forgotmyname

How longs a piece of string???

Without knowing the average MPG for each journey then nobody knows the anwer.

5miles in 20 minutes =15mph average, 15 miles = 45mph.

So does your car get 3x more mpg at 45mph than it does at 15mph?

There is the answer. Yes = 2 No = 1

steve-L

Its really not just about fuel.

The start-stop route will wear the clutch as well.

It really depends on your car....

Journey A is a 5 mile journey mainly at 20-30mph.
Big diesel = PANTS MPG then engine is hardly warm by the time you arrive.... you already damaged the engine as much as the other journey already running cold and you added significant clutch wear and DMF

Small 1.2 Petrol ..... gets good MPG, wears clutch more

Journey B is a 15 mile journey at 60mph on motorway.
Big diesel gets chance to warm up, burn off DPF (or a good start) and wear clutch/DMF less
Small petrol probalby gets less MPG at 75mph than big deisel.