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Using Economy Mode.

bwanamdevu

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It is relatively easy to understand the Kers system of Regenerative Braking but what actually happens in the Mode system?

I use the Economy Mode most of the time but when the car is running in this mode, what is happening in the ‘innards’ of the car? What is the difference in the internal mechanics of the motor when you switch backwards and forwards between modes? How does turning ‘economy’ on suddenly give you a greater range?

I might have not expressed myself to well but I hope that I have conveyed the general idea of what I want to know.

And a ‘Dummies’ guide to the problem please.
 
Hi, as far as I can tell it makes the throttle less responsive if you push it lightly, if you flick it to sports the car takes off like a rocket 🤣
 
I assume it delivers less power based on how hard you push your foot down. It also makes the steering lighter and puts the fans on eco mode limiting its power I believe.
 
The biggest factor will be the ramp rates applied to power demand.
A higher rate of acceleration to reach a given speed will consume more energy than a lower rate of acceleration to reach the same speed.
The ramp rate becomes progressively higher as you run from Eco to Normal to Sport.
 
"A higher rate of acceleration to reach a given speed will consume more energy than a lower rate of acceleration to reach the same speed."

I really don't doubt that but it is for a shorter time so I often wonder just how much difference it really makes.
 
I have always assumed the amount of charge used would be similar to my ICE petrol used. For example if I did a 200 mile trip in my 4.0 ltr Jaguar XJ depending on how I drove it I could get at best 22mpg or if giving some wellie now and again that could drop as low as 14 mpg.
i have only done one exactly the same 200 mile trip where I drove conservatively and averaged 3.1 miles per KWHr. Next month I am doing he same trip again and will report on wellie miles per ZkWHr.
 
"A higher rate of acceleration to reach a given speed will consume more energy than a lower rate of acceleration to reach the same speed."

I really don't doubt that but it is for a shorter time so I often wonder just how much difference it really makes.
Theoretically Smokie, it makes no difference at all.

Remembering the equations from my long past University studies in Physics, to move an object from Point A to Point B will require the same amount of energy, no matter if it takes a longer or shorter time.
When time is involved in the calculation, we are working out the power applied so more power, shorter time and hence a faster rate of acceleration to get to Point B. Accelerating more slowly uses a lower power and only changes to time involved and will consume the same total amount of cumulative energy but applied more slowly.

Here endeth the Physics lesson.
 
Lighter steering and dumbed down heating plus a different pedal response.
Similar to this:
Pedal map.png
 
Also affects the brakes according to the manual.

Braking Response Mode
EHBS provides 2 different braking response modes:
• Standard: provides normal brake boost and brake pedal
feel.
• Sport: provides extra brake boost and a more sensitive
brake pedal feeling.
The user is able to select the response mode via the
drive mode selection function - refer to "Electric Drive
Transmission" in the "Starting and Driving" section.
Note: If the driving mode is switched whilst driving,
the braking response may not change immediately.
After the vehicle comes to a halt and the brake pedal
released the mode will switch automatically.
 
Theoretically Smokie, it makes no difference at all.

Remembering the equations from my long past University studies in Physics, to move an object from Point A to Point B will require the same amount of energy, no matter if it takes a longer or shorter time.
When time is involved in the calculation, we are working out the power applied so more power, shorter time and hence a faster rate of acceleration to get to Point B. Accelerating more slowly uses a lower power and only changes to time involved and will consume the same total amount of cumulative energy but applied more slowly.

Here endeth the Physics lesson.
Except unfortunately, a battery is not a linear power source. Taking power out faster reduces the total stored energy faster than at a slower speed. This addition energy loss outweighs any savings made from getting to the destination quicker resulting in reduced range.
 
"A higher rate of acceleration to reach a given speed will consume more energy than a lower rate of acceleration to reach the same speed."

I really don't doubt that but it is for a shorter time so I often wonder just how much difference it really makes.
The quantitative effect is difficult to judge without doing controlled measurements but there will still be a difference. Copper losses will be higher with higher demand and you don't get that back because the time is shorter.
 
Hmmm interesting discussion but I'm going to backtrack a little on my initial statement as clearly if you are ona journey and travel over 70 you use more juice than if you travel at 60. I have no idea of the physics behind it.

My logic is often flawed :)
 
Same reason an ICE car will use more gas the faster you go the more energy needed to keep the car at that speed, rolling resistance, wind resistance etc etc
 
Over 40 mph and air resistance is the major factor. For larger objects at higher speeds, ait resistance is dependent on the square of velocity. The air resistance increase between 60 mph and 70mph is more than 30%. The quicker you get to high speed the longer you spend at higher air resistance levels. Air resistance is usually the thing that determines a car's top speed.
 
I was wondering if its possible / safe to change Modes while driving?
 
Quite safe to change on the go. I've done this plenty of times although I must admit that 90+ percent of my driving tends to be in Normal mode.
 
Hmmm interesting discussion but I'm going to backtrack a little on my initial statement as clearly if you are ona journey and travel over 70 you use more juice than if you travel at 60. I have no idea of the physics behind it.

My logic is often flawed :)
That’s why F1 spend so much on testing in very very expensive wind tunnels
 
a thought ... does the eco mode shut down some of the heating/climate controls to save the battery ?
 
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