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Tesla Model Y, 2022
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Bjorn Nyland has started rushing through videos with limited research nowadays. This test must be performed on multiple days to avoid battery heat from influencing the efficiency. However, it is quite possible that the payload doesn't alter the centre of gravity at all, so the efficiency doesn't get affected. On my Model Y, I noticed that the driving style and not the no of occupants determined the efficiency. When I drive in a chilled manner, I get better efficiency even on a fully-loaded car compared to driving alone.
 

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2020 VW ID3
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He is not the first to discover this phenomenon.

A few years ago, probably on this forum, I read an account of a conversation a journalist had with the technical development people at Nissan. The journalist asked what range the ENV 200 van could achieve fully loaded and why this was not included in the publicity about the vehicle. The reply was that they had done a full range of tests on the van fully loaded and found no reduction in range compared with the unloaded figures. They then decided that no-one would believe them so just omitted the information from the vehicle specifications.
 

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Going uphill it's going to take more energy to drive a heavier vehicle but, of course, with an EV you get a good bit of that back on the way down the hill. Similarly with acceleration and deceleration. On the level at constant speed, the energy is consumed by friction in the drive train and aerodynamic losses which are both pretty independent of load.

That's the only expalnation I can come up with.

It would be interesting to see a comparison tests done on an HGV!
 

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Soul EV 30kWh 2017
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437 Posts
Center of gravity (the point at which gravity exerts its effect on the car) governs stability, but has nothing to do with economy.

Newton's Law: Force = Mass x Acceleration tells us that, when you accelerate a body, the force required (and therefore the energy consumed) is proportional to the mass of the body. However, if you accelerate once to reach cruising speed, and then perform the journey at constant speed, most of the energy will be consumed, as has been pointed out, in overcoming friction and air resistance, so the effect of acceleration will be small and lost in the noise.

Change the scenario to a van doing local deliveries in city traffic (so lots of acceleration and deceleration) and you will see a pronounced dependence on load.
 

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2020 VW ID3
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Center of gravity (the point at which gravity exerts its effect on the car) governs stability, but has nothing to do with economy.

Newton's Law: Force = Mass x Acceleration tells us that, when you accelerate a body, the force required (and therefore the energy consumed) is proportional to the mass of the body. However, if you accelerate once to reach cruising speed, and then perform the journey at constant speed, most of the energy will be consumed, as has been pointed out, in overcoming friction and air resistance, so the effect of acceleration will be small and lost in the noise.

Change the scenario to a van doing local deliveries in city traffic (so lots of acceleration and deceleration) and you will see a pronounced dependence on load.
Don't forget the effect of regeneration which will also increase with load.
 

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Kia Soul EV 2020
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He is not the first to discover this phenomenon.

A few years ago, probably on this forum, I read an account of a conversation a journalist had with the technical development people at Nissan. The journalist asked what range the ENV 200 van could achieve fully loaded and why this was not included in the publicity about the vehicle. The reply was that they had done a full range of tests on the van fully loaded and found no reduction in range compared with the unloaded figures. They then decided that no-one would believe them so just omitted the information from the vehicle specifications.
Do you mind trying to find this discussion?

Anyway, I was looking at the problem as in: what is the difference from ICE? Regen is an obvious one, but possible major reason. Power curve is my next choice, as ICE are fairly inefficient at low gears.

There was an obvious issue with the choice of route/speed combo by Bjorn, but even then the consumption should not be the same.
 

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Soul EV 30kWh 2017
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Probably not a surprise but I bet ice cars are more sensitive to weight and would see a greater effect on efficiency.
I wouldn't mind accepting that bet. Taking into account TomH's point that EVs give you back some of your acceleration energy when regenerative braking is employed, I would put money on less effect of mass on efficiency.
 

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KIA Soul EV First Edition
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160 Posts
maybe the weight lowered the car and made it more aerodynamic ;)

The latest one from Bjorn with him trying to hookup the sister in law, was cringey for me. Though I am enjoying the old Soul degredation videos (I wish he would do 30kWh next). He was suggesting not to buy second hand Kia Soul, but not making it clear that 27kWh have lots of examples of degredation (especially in extereme weather areas like Arizona and Norway), whereas the 30kWh doesn't seem to have this issue. I know at 52K there was no degredation in my old 30kWh, and @Cabby7 old 30kWh had over 80K with almost daily 100% chargeing w/o any noticable degradation.
 

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What is the obsession with everything being on a YT video these days. I can't be bothered and haven't watched it and I would have been quite happy with a spreadsheet table. And before anyone says, I know it's taken me longer to type this than watch the video !!!!
 
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