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Depends on the EV but slow works. According to the following thread an US volt did 83 miles on a charge, this was at 10mph in a car with a normal EV range of 40/50 miles.

80 mile club

Generally 40 or less as its wind resistance that reduces range and resistance (drag) climbs as the square of the speed not linearly. Electric Motors have a speed where they are most efficient, again varies by EV.

However why? Apply boot and smile, these EV's are fun.(y):)
 

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Here's a graph of apparently showing efficiency on an electric car allegedly (not sure if it's an accurate representation)...


So that seems to indicate that slower is not necessarily better, as the optimum efficiency appears to be between about 15-20mph.. I'm sure there are some physics boffins on here who would be able to prove or disprove that this graph is correct.
 

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Yep, they all vary a bit, but 20mph is about right.

In the real world, aim for a GPS 57mph. Most speedos will show this as "60" so you won't pee other people off too much, and you'll slowly catch up to the back of lorries (rather than them slowly catching up to the back of you)
 

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I was going to say 20mph before I looked at the chart. I managed 2.7 miles in a Leaf on Turtle mode at 20mph with a slight up-hill at the end.

Needless to say this was through necessity not choice and in a town at 1:30 am so not inconveniencing any other users (with the exception of the recovery company who did not get any work from me that night;))
 

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Here's a graph of apparently showing efficiency on an electric car allegedly (not sure if it's an accurate representation)...


So that seems to indicate that slower is not necessarily better, as the optimum efficiency appears to be between about 15-20mph.. I'm sure there are some physics boffins on here who would be able to prove or disprove that this graph is correct.
The inverter and electric motor both become less efficient at low speed as the graph shows with the upturn in consumption. So you really don't want to drive at less than 10 mph in start stop traffic if at all possible.
 

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I seem to get my best range around 60mph, used to think if I drove slower I would go farther but that is not the case, it's handy really because I enjoy having fun in MK.
 

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I think on a Tesla Model S the maximum range speed is about 25 MPH with the range at 45 MPH being the same as the range at 5MPH. That's from memory mind and may have changed on the latest cars.
 

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Here's a graph of apparently showing efficiency on an electric car allegedly (not sure if it's an accurate representation)...


So that seems to indicate that slower is not necessarily better, as the optimum efficiency appears to be between about 15-20mph.. I'm sure there are some physics boffins on here who would be able to prove or disprove that this graph is correct.
It is looking quite correct for my understanding and experience

ICE car have a big waste of energy just for have the ICE spinning without load.
Also ICE efficiency increase with the increase of the load.

So .. all we know of fuel economy and speed from our ICE cars .. is not applicable for EV

The EV motor+battery are in general more efficient at low power (except at extreme low power .. and this level of low power is possibly a function of the EV engine size used (tesla use quite a big EV engine)

Definitely my Outlander PHEV at 20km/h or 15mph .. allow to drive for ever with its little 12kwh battery

Already above 60km/h, due to the car size and aerodynamic .. it is very much noticeable the reduction of EV range
 

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For me the most important question is what speed should I travel along the motorway to get there the fastest, for my Zoe with 43kW AC charging I've concluded it's somewhere between 58 and 65 mph but this changes with the spacing of the rapid chargers weather, terrain etc, you want to arrive at a charger with as low a state of charge as you can with a little contingency should the charger not be available to maximise the charging rate. When the charger that I can sensibly make is a little closer I go faster. Remember that it takes about 35 minutes for a 30 minute charge including the time to leave the motorway, find the charger and start the charge then disconnect from the charger and get back up to speed on the motorway after the charge. When I first got the car I had a play with a spread sheet plotting speed against range and the optimum speed is nowhere near as sharp a point as I had expected, I used the range projections on the Zoe range predictor app.

Throw in the total distance to your next charge and the equation all changes, in the end you just have to use your judgement.
 

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How does acceleration fit in. In theory with the same top speed below about 30 so little air resistance effect and long enough between starts and stops that you always reach this cruising speed then whether you burn the same energy accelerating quickly or slowly you should use the same total energy for the same distance travelled.
 

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How does acceleration fit in. In theory with the same top speed below about 30 so little air resistance effect and long enough between starts and stops that you always reach this cruising speed then whether you burn the same energy accelerating quickly or slowly you should use the same total energy for the same distance travelled.
Slow acceleration is what my car appreciate for increase EV range .. in practice above a minimum power out .. more power from Ev motor and battery cause more 'waste" ... if you consider the ideal speed around 20km/h and the little energy needed for travel at this speed .. you may see how little power should be used for accelerate in ideal efficiency

Anyhow .. more then acceleration ... trying to avoid change of speed is the key for efficient driving ... even if there is regen breaking, still 20/30% of the kinetic energy get wasted ... on motorway or at constant speed I disable the automatic regen breaking on my car .. so every time I lift the foot on the gas pedal, the car automatically try to keep the same speed

Anyhow ... thinking of max efficiency would be causing to drive too slow ... so ... in my case ... I don't care much ... in my case .. when battery is discharged, I still have a tank full of petrol ready to kick in ... since my car start the ICE automatically when power request is above 60kw ... my ecological drive is to take care to don't use more then 60kw of power when driving ... and in few cases if my Ev range need to be adjusted for the 1 or 2 km missing for arrive at destination without kick in the ICE, then I may slow down on motorway (at 120km/h on clock the EV range is half or less compared to 60km/h drive), or select a shorter path on slower streets
 

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Depends on the EV but slow works. According to the following thread an US volt did 83 miles on a charge, this was at 10mph in a car with a normal EV range of 40/50 miles.

80 mile club

Generally 40 or less as its wind resistance that reduces range and resistance (drag) climbs as the square of the speed not linearly. Electric Motors have a speed where they are most efficient, again varies by EV.

However why? Apply boot and smile, these EV's are fun.(y):)
Closer to home, Top Gear magazine managed to get an Ampera over 60 miles on battery: all the way to France and back again.

Ampera in Top Gear Channel Tunnel Challenge | News – Vauxhall Motors UK
 

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After having my eNV200 for nearly 2 months and doing over 1,000 miles on motorways and A & B roads, I can certainly notice the exponential drop-off in range once I start having longer periods above 50-55 mph. In London at 20 mph I'm sure I could even exceed the official NEDC range of 106 miles. Sticking to the A roads, aiming for up to 50 mph and avoiding any parallel motorway certainly makes sense for maximum miles.
 

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I cant be arsed driving along at 50, and just put up with the reduced range that comes from driving at 70. However i've noticed something interesting on the few occasions i did try to drive slower.

Unless your going to just sit at 56 in the inside behind lorries, the two lane motorways and dual carridgeways around here mean that not doing 70 can actually end up using MORE power.

A couple of times i've tried to drive at 60-65ish and found that you end up constantly changing lanes and speeding up and slowing down. 60 means your going fast enough that you need to overtake the HGV's that are sat in the left lane. But the higher speed traffic doing 70-75 in the outside makes it difficult to actually get out and pass them. Often you end up slowing down behind the lorry, waiting for a gap, then accellerating out into the gap, passing the truck at 60 with several cars now wedged up your arse, before pulling back in, and having to repeat the whole thing a few hundred meters up the road when you catch the next lorry. The constant braking (even with regen) and then accellerating again seems to use more power than just driving at 70.

Its also more relaxing just to do 70 and keep up with traffic.

I guess picking slower A roads instead might work for some routes, but they're not really an option for the likes of my commute, as they either dont exist (because the A road is dual carridgeway), or they are more like B roads, or roads thru city streets or villages which add huge amounts of time and arent hugely efficient as they're hilly or have lots of speed variations etc.
 
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