We need a snow driving mode

[Peddyr]

Lived in New England all my life, and in my opinion, driving in the snow is more dependant on the driver's skill level than the vehicle itself. The Lightning with AWD and weight is easily the best vehicle I've ever driven in the snow or slippery conditions. That said, giving those who need additional assistance, the snow option if they want to pay for it isn't the worst idea I've ever heard. It's just not for me.

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[Grease Lightning]

Serious question, what does eco-mode do? It's my understanding there isn't significant efficiency loss from accelerating quickly in EVs.

In my previous Escape, the Ioniq, my 2017 “e-assist” Silverado, and multiple Prii the eco mode went beyond throttle response, but also adjusted how responsive climate controls reacted. So like on a freeway drive once warm/cool and up to speed, if you entered eco mode it would slow down elements such as the a/c to make it say “a/c lite” and reduce the amount of energy used.

Then as you as mentioned the throttle response was different so you conserve energy. Such at rapid acceleration, yes does cost you energy. “Significant” is subjective but the extra energy is quantifiable and easy to view through Carscanner. My M3 and its consumption graphs do a great job of showing you the impacts of a heavier foot. So if you are more of a hypermiler type driver, it is of great benefit.

 

[Firn]

Then as you as mentioned the throttle response was different so you conserve energy. Such at rapid acceleration, yes does cost you energy. “Significant” is subjective but the extra energy is quantifiable and easy to view through Carscanner. My M3 and its consumption graphs do a great job of showing you the impacts of a heavier foot. So if you are more of a hypermiler type driver, it is of great benefit.

The big thing here though is that and EV drivetrain doesn't really change efficiency when pressed hard, and ICE drivetrain does greatly.

Although when accelerating hard you use more current, you do so for a shorter period of time, and hence the energy consumed isn't really much different that having lower current for a longer period of time.

In an ICE engine it is different, high load but low RPM (accelerating slowly) is much more efficient than high load but high RPM.

Point being, accelerating hard in an EV doesn't really cost you much "extra energy", you just consume at a higher rate for a shorter period. That is different than an ice engine since it changes efficiency.

 

[daveross1212]

The big thing here though is that and EV drivetrain doesn't really change efficiency when pressed hard, and ICE drivetrain does greatly.

Although when accelerating hard you use more current, you do so for a shorter period of time, and hence the energy consumed isn't really much different that having lower current for a longer period of time.

In an ICE engine it is different, high load but low RPM (accelerating slowly) is much more efficient than high load but high RPM.

Point being, accelerating hard in an EV doesn't really cost you much "extra energy", you just consume at a higher rate for a shorter period. That is different than an ice engine since it changes efficiency.

also worth adding that some recent research is showing that hard acceleration is actually good for battery longevity (also the opposite of ICE)!

 

[Adventureboy]

also worth adding that some recent research is showing that hard acceleration is actually good for battery longevity (also the opposite of ICE)!

I'm testing this theory. No babying here - Got it and will use it. My SOH is 100% after 2 years and 30,000mi.

 

[Henry Ford]

The big thing here though is that and EV drivetrain doesn't really change efficiency when pressed hard, and ICE drivetrain does greatly.

Although when accelerating hard you use more current, you do so for a shorter period of time, and hence the energy consumed isn't really much different that having lower current for a longer period of time.

In an ICE engine it is different, high load but low RPM (accelerating slowly) is much more efficient than high load but high RPM.

Point being, accelerating hard in an EV doesn't really cost you much "extra energy", you just consume at a higher rate for a shorter period. That is different than an ice engine since it changes efficiency.

This is my understanding. I'm no expert but I don't see where you could lose efficiency by accelerating hard except for wheel spin. Heat loss? Not really.

ICE is a whole other animal. They are most efficient at a certain RPM and load and any variation from that hurts efficiency. There's probably drivetrain efficiency loss due to shifting too but that's beyond my grasp.

 

[farmtruck]

Serious question, what does eco-mode do? It's my understanding there isn't significant efficiency loss from accelerating quickly in EVs.

What I could see is eco-mode disconnecting a wheel motor if the load is low enough to allow it.

 

[Grease Lightning]

EV drivetrain doesn't really change efficiency when pressed hard

That would be true in our Lightnings, but that is not true in all EV, so word of caution for more definitive type generalizations.

There are EV that can decouple the front and rear drive train after the needed acceleration has been completed and the needed energy to maintain a speed. So in those types of EVs, yes an “eco” mode does provide acceleration savings while only having those two or more big motors spinning when you hammer it. Similar to how a hybrid/PHEV can force the ICE element on at certain loads, but a gentle throttle can keep it in EV mode.

much "extra energy"

Again “much” and “extra” are subjective to the user. As your statement notes, it does use extra energy and the quantitative aspect varies by duration of time, conditions, frequency, and such. If I am getting on a freeway entrance and going straight down a flat road with no wind, sure little impact. If I am in the town jackrabbit starts or on a two lane highway constantly passing people by “haul’n ballz”, then again a lot more impact.

But I also love my Lightning’s efficiency over 20k is 2.4-2.5 m/kWh average so I would always take the option to control my tech rather then the tech controlling me.

 

[Firn]

That would be true in our Lightnings, but that is not true in all EV, so word of caution for more definitive type generalizations.

There are EV that can decouple the front and rear drive train after the needed acceleration has been completed and the needed energy to maintain a speed. So in those types of EVs, yes an “eco” mode does provide acceleration savings while only having those two or more big motors spinning when you hammer it. Similar to how a hybrid/PHEV can force the ICE element on at certain loads, but a gentle throttle can keep it in EV mode.

Of the ones I have seen that decouple the front motor they claim to do so during steady state driving, but that does not mean they do so under acceleration, even light or moderate acceleration. The effect of decoupling the motor is very slight and arguably would be insignificant in the 10-30 second acceleration events, as opposed to the multi-hour cruise time frame. Remember, we are discussing the difference between acceleration styles, not general efficiency.

Again “much” and “extra” are subjective to the user. As your statement notes, it does use extra energy and the quantitative aspect varies by duration of time, conditions, frequency, and such. If I am getting on a freeway entrance and going straight down a flat road with no wind, sure little impact. If I am in the town jackrabbit starts or on a two lane highway constantly passing people by “haul’n ballz”, then again a lot more impact.

But I also love my Lightning’s efficiency over 20k is 2.4-2.5 m/kWh average so I would always take the option to control my tech rather then the tech controlling me.

No, quantity of energy is the ONLY measure here, and for that time must to be included. Trip efficiency is a measure of how much energy was used over the duration. Comparing the rate of energy usage is simply comparing peak horsepower applied, not the quantity. You don't measure a trip by the KW, you measure it by the KWh. And the comparison is one acceleration style to the next, to achieve the same effect. Obviously driving much faster uses more energy, just as driving much farther does. We know driving at a high rate of speed uses both energy at a higher rate and a larger quantity of energy (for the same drive). The question is if how fast you get to the same speed makes a difference. To have the discussion you have to control the variables otherwise we are comparing a track day vs driving grandma three blocks to church.

 

[astrand1]

I disagree and believe that this is more of a driver problem than a problem with current throttle mapping. Also, regen is fine in winter conditions just as long as you don't treat the throttle like an on-off switch. How else have other EVs with regen and no way to turn off or dial down the inversion strength manage to operate in the snow after all these years?

I agree. My truck normally just stays in normal mode with one pedal on. For me it’s all about modulating the pedal correctly to slow down and speed up in snow. I’ve not had a problem at all. And I’m on the stock hankooks. This truck has such good traction it really is impressive.

 

[Grease Lightning]

Of the ones I have seen that decouple the front motor they claim to do so during steady state driving, but that does not mean they do so under acceleration, even light or moderate acceleration. The effect of decoupling the motor is very slight and arguably would be insignificant in the 10-30 second acceleration events, as opposed to the multi-hour cruise time frame. Remember, we are discussing the difference between acceleration styles, not general efficiency.



No, quantity of energy is the ONLY measure here, and for that time must to be included. Trip efficiency is a measure of how much energy was used over the duration. Comparing the rate of energy usage is simply comparing peak horsepower applied, not the quantity. You don't measure a trip by the KW, you measure it by the KWh. And the comparison is one acceleration style to the next, to achieve the same effect. Obviously driving much faster uses more energy, just as driving much farther does. We know driving at a high rate of speed uses both energy at a higher rate and a larger quantity of energy (for the same drive). The question is if how fast you get to the same speed makes a difference. To have the discussion you have to control the variables otherwise we are comparing a track day vs driving grandma three blocks to church.

You missed my after acceleration for the decouple….

And yes there is more to “total energy” when it comes to efficiency and if slow or hard acceleration is the best case. If I expend 1 kW in 1 minute, I am way less efficient per mile than 1 kW over an hour, for example. Then the duration of the draw at 1kW per minute directly correlates to when the 1 kW per hour becomes the norm and has greater influence on overriding the less efficient factor. For example of your efficiency was .5 m/kW for 9 measurements and the 10th measurement was 3.5 m/kW your average is only .8 m/kW. Whereas the inverse would give you 3.2 m/kW average.

So as I stated you have to take into account the energy expended based on the sample. Such as how long the more demanding draw is, how frequently that demand occurs, not to mention all the other environmental factors that would impact such a calculation.

 

[Firn]

You missed my after acceleration for the decouple….

And yes there is more to “total energy” when it comes to efficiency and if slow or hard acceleration is the best case. If I expend 1 kW in 1 minute, I am way less efficient per mile than 1 kW over an hour, for example. Then the duration of the draw at 1kW per minute directly correlates to when the 1 kW per hour becomes the norm and has greater influence on overriding the less efficient factor. For example of your efficiency was .5 m/kW for 9 measurements and the 10th measurement was 3.5 m/kW your average is only .8 m/kW. Whereas the inverse would give you 3.2 m/kW average.

So as I stated you have to take into account the energy expended based on the sample. Such as how long the more demanding draw is, how frequently that demand occurs, not to mention all the other environmental factors that would impact such a calculation.

Let's try this another way then.

You are taking a mass and giving it kinetic energy, and a little heat. Conservation of energy states that you cannot apply different amounts of energy to two identical systems but achieve the same result. So provided the efficiency of the drivetrain stays the same achieving the same kinetic energy requires the same amount of energy.

Apply 100kw for 10 seconds, or 50kw for 20 seconds, you will achieve the same kinetic energy

The reason this doesn't work with gas engines is that the efficiency changes, in one situation say 30% of the energy goes into heat, the the other 70% does. That isn't true, at least not anywhere near the same extent, with electric systems.

 

[Grease Lightning]

Apply 100kw for 10 seconds, or 50kw for 20 seconds, you will achieve the same kinetic energy

What you applied time. Shocked. Thanks for proving my point without proving my point

Also thanks for again showing the lack of grasping that I am talking efficiency not the total energy.

And by the way kinetic energy includes a factor you have yet to consider as you are obsessing about total energy rather then my discussion on efficiency… speed…

KE depends on an object's mass and speed, and is calculated using the formula KE = 1/2 * mass * velocity^2 🫳

 

[Firn]

What you applied time. Shocked. Thanks for proving my point without proving my point

Also thanks for again showing the lack of grasping that I am talking efficiency not the total energy.

And by the way kinetic energy includes a factor you have yet to consider as you are obsessing about total energy rather then my discussion on efficiency… speed…

KE depends on an object's mass and speed, and is calculated using the formula KE = 1/2 * mass * velocity^2 🫳

Did you get lost here?

You were the one who said you DID NOT need time, it was ME who said time was a component.

The quantity of energy IS the efficiency. The quantity of energy needed to complete the same drive. That is literally the mi/kwh we are talking about, the quantity of energy for a single drive. Anything other than quantity is the efficiency of the driveline, aka how much energy is lost in heat and that is NOT what you were describing.

Yes, kinetic energy, speed. In ALL of this the SPEED is the SAME. we have only been discussing changes in efficiency to get to that speed. How hard you accelerate to get to that speed. I literally described this in detail above.

Seriously man...please go back and read this whole thing again.

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