Speed v. Range - analysis using ABRP

[Prof1967]

I seem to remember that the optimal speed for fuel efficiency for an ICE car was on average 56mph with consumption increasing surprisingly rapidly once over. I have not seen similar for EV's, does anyone have info on this?

I have a friend who was told this 30 years ago so as a consequence has never driven above 56mph. Swears it makes a huge difference to his consumption.

Personally I could not tolerate being constantly overtaken by all other road users.

 

[shayjeffs]

I seem to remember that the optimal speed for fuel efficiency for an ICE car was on average 56mph with consumption increasing surprisingly rapidly once over. I have not seen similar for EV's, does anyone have info on this?

I do airport runs (about 3 a day) from Henley-on-Thames to Heathrow nearly everyday. There is a speed limit of 50 mph on the M4 between Maidenhead and Heathrow. I generally get 4.7 m/kw on these trips because of the 50 mph limit. Also temperature averaging about 20 degrees.

If I go to Gatwick (M4 then M25) this drops to 4 m/kw doing 70mph on the M25 part.

Going to Luton (M40 - M25 -M1) doing 70 all the way drops to 3.7 m/kw.

Love the 50 mph limit on the M4.

 

[BugEyed]

I have a friend who was told this 30 years ago so as a consequence has never driven above 56mph. Swears it makes a huge difference to his consumption.

Personally I could not tolerate being constantly overtaken by all other road users.

Around my neck of the woods, apart from on motorways occasionally, you rarely sustain more than that for more than a handful of miles, at which point you are then stuck in the next queue of slow moving traffic. Having a short range EV taught me that it was no quicker point to point driving faster but the range would drop quickly.

 

[Robf]

As well as the optimum speed for engine efficiency, I seem to remember that aero dynamics played a part as well. I think the dynamics go to pot over a certain speed. I wonder what this would be for the MG? I guess it also depends on which way the wind is blowing

 

[Prof1967]

Part 1 of the attached article seems to debunk the 56mph myth.

Fuel cost: How to save petrol and diesel

With weak competition adding to fuel prices, are drivers doing the right things to save money?

www.bbc.co.uk

With the massive increases in petrol and diesel prices I'm glad I moved to electric when I did.

 

[shayjeffs]

Part 1 of the attached article seems to debunk the 56mph myth.

Fuel cost: How to save petrol and diesel

With weak competition adding to fuel prices, are drivers doing the right things to save money?

www.bbc.co.uk

With the massive increases in petrol and diesel prices I'm glad I moved to electric when I did.

I couldn’t agree more.
With regards to the BBC article, I’ll take that with a pinch of salt. Anything on the BBC is dubious IMHO.

 

[smokie]

Anything on the BBC is dubious IMHO.

Ridiculous statement, and no, I don't work for them.

 

[shayjeffs]

Whatever.
Great thing about a democracy? You can have an opinion.

 

[EVsince2016]

I couldn’t agree more.
With regards to the BBC article, I’ll take that with a pinch of salt. Anything on the BBC is dubious IMHO.

That BBC article seems correct and well informed.

I have often complained to the BBC about inaccurate or misleading articles in recent years, their answers are a tad PC, we need balance etc as a cover to they don't know what's right!

 

[Prof1967]

looks as if they got their info from the RAC so should be reasonably reliable.

Think with modern engine management systems the amount of fuel injected is tightly regulated so no more than necessary is being burned regardless of speed.

On a side note, a long stretch of the M4 where I live has a speed limit of 50mph as cars supposedly produce less pollution at that speed. I wonder whether I could get away with going faster as my MG effectively has zero emissions.

 

[BugEyed]

looks as if they got their info from the RAC so should be reasonably reliable.

The RAC Foundation is not the knowledgeable organisation that the RAC may have been before.

Think with modern engine management systems the amount of fuel injected is tightly regulated so no more than necessary is being burned regardless of speed.

It would be nice to think that, but there are contrasting requirements such as keeping sufficient unburnt fuel in the exhaust to keep the catalytic converter hot.

 

[Hairyfool]

Look forward to when AA and RAC route planners include electric vehicles in the options

It appears that VW are providing a route planner geared for their EVs

Electric Vehicle Route Planner

Choose the VW that closest matches your mileage specs then it will calculate including the stop(s)

Perhaps MG should take a look