Regenerative braking and range
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Not much. You'll technically get more range in HIGH though.
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I’ve found a fairly significant difference between the two in range, but to be fair it’s literally been years since I tried standard regen.
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EVs are very heavy for their size, and their friction brake components are probably engineered on the assumption that regeneration will handle a certain amount of braking load. Recovering regenerative energy aside, why would you want to put the additional wear and tear on your friction brakes? In nine years of driving EVs, we've never had to deal with worn brake pads, warped rotors, or any other brake service we've had to have done on our ICE cars.
I do alot of driving on secondary roads. When passing a truck I'll accelerate from 45 to 80 during the pass. I'd like let the car slowly return to 60 (fastest I'll go on rural road posted at 50). Right now I get regeneration, which I don't need and its hurting efficiency. I'd rather have the option of turning it off.
As far as brake life I usually need to replace my ICE brakes at around 60k miles. Most cases there is decent pad material left but the rotors are too rusted to use from sitting unused.
As far as brake life I usually need to replace my ICE brakes at around 60k miles. Most cases there is decent pad material left but the rotors are too rusted to use from sitting unused.
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Regenerative braking returns energy to the battery pack. It enhances efficiency, not hurts it.
If you are having to replace rotors at 60k miles on an ICE car, those brakes are getting a lot of use. They are not spending so much time being unused that they would simply rust away. In fact, I've never heard of rotors just rusting away, and I live in a humid salt-air climate.
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It usually happens if the car sits a week in the rain (I commute by train so do not use the car mid week). After the week the car will show slight vibration when braking from 70. With in a month the vibration will occur when braking from 30.
As far as regeneration placing energy back into the battery has a round trip efficiency of around 50%. I'd rather have the choice of regeneration levels (including zero). Besides the previously mentioned passing maneuver (where zero regeneration would result in smoother drive) I would also like zero regeneration for driving in heavy snow especially when combining snow with hilly winding roads.
As far as regeneration placing energy back into the battery has a round trip efficiency of around 50%. I'd rather have the choice of regeneration levels (including zero). Besides the previously mentioned passing maneuver (where zero regeneration would result in smoother drive) I would also like zero regeneration for driving in heavy snow especially when combining snow with hilly winding roads.
I've learned that you can easily execute the passing maneuver without engaging the regen after the pass (even if regen is set to high). There is no need to fully release the accelerator pedal after the pass. With a little practice, you should be able coast the car with the car with the charge/discharge indicator near the vertical neutral position.
With that said, it also should be easy to program in a zero regen for those that really want it too.
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Although it requires some technique to drive smoothly, regen does not hurt efficiency.
I believe it does. It is more efficient to coast from 75 to 55 than to regen from 75 to 55 continuing at 55. Even if I'm wrong it's still tedious to drive smoothly with multiple passing situations on secondary roads. After every pass I would have to hold partial accelerator (throttle) to keep from constant hard accelerating/decelerating. Much nicer to have the option of coasting. At least there wouldn't be a decel head bob after each pass.
I realize this is a specific, low frequency, driving scenario, but I am driving 120 miles on secondary roads (each direction) every weekend during ski season.
I realize this is a specific, low frequency, driving scenario, but I am driving 120 miles on secondary roads (each direction) every weekend during ski season.
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I don't think you understand what regenerative braking is. A car coasts down in speed due to pushing air aside, to air friction, to road friction, to internal friction and, if going uphill, due to gravity. The energy that is lost in such deceleration is wasted (unless your goal is to heat up the air, the surface of your car, the roadway, and your tires while slowing the car). Regenerative braking is a process by which some of that energy is recovered and stored in the battery to be available for future propulsion. In terms of using the least energy possible over the course of a trip, regenerative braking is more efficient than coasting down as a means of reducing speed in an EV.
If you prefer not to bother with the easy and intuitive task of modulating the accelerator pedal to meter regenerative braking, that's fine. But you really ought to quit repeatedly claiming it's more energy efficient to coast down. It's not, and it's misleading to new EV drivers who are trying to understand regenerative braking and its advantages.
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Well
www.greencarfuture.com
Regenerative Braking Vs. Coasting: Which is Better? - Green Car Future
As electric cars firmly enter the mainstream, more and more debates are opening up about these vehicles and what they can and can’t do, which kinds of
www.greencarfuture.com
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I don't think I can trust a website with ads between every. single. paragraph.
That being said, their argument makes no sense. With coasting, as @hmp10 said, all the energy is just lost. With regen, you're gaining (some) of that energy back and putting it into the battery. They're trying to claim regen is worse because there are more places the energy can be lost? Huh? Either way, you're still recuperating some of that energy that is completely lost with coasting.
You can't believe everything you read on the Internet. You can functionally 'coast' if you feather the accelerator correctly. That's the beauty of one pedal driving.
That being said, their argument makes no sense. With coasting, as @hmp10 said, all the energy is just lost. With regen, you're gaining (some) of that energy back and putting it into the battery. They're trying to claim regen is worse because there are more places the energy can be lost? Huh? Either way, you're still recuperating some of that energy that is completely lost with coasting.
You can't believe everything you read on the Internet. You can functionally 'coast' if you feather the accelerator correctly. That's the beauty of one pedal driving.
Didn't like that what about Porsche's take
I would like it if drivers had an option. I was surprised to learn this car only has two levels of regen and it cannot be turned entirely off. My other EV allows it to be turned off and coast. It also uses regen when the actual brake pedal is pressed, unlike the Lucid. That said, I have gotten used to it and drive in the high regeneration setting all the time.
elin
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I'm pretty sure coasting is more efficient to get down to a specific speed and continue with that lower speed. You travel a further distance without any losses that would have occurred with regen (regen does not recapture with 100% efficiency).
I don’t know the physics, so I’m not going to pretend to be an expert. All I know is when I drive downhill from Nederland (8200 ft) to Boulder (5600 ft) on high regen, I end up with a few kWh MORE in my battery pack than when I started. That would not happen with coasting. I might end up using almost no energy that whole way down, but I wouldn’t be gaining energy.
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Well
Regenerative Braking Vs. Coasting: Which is Better? - Green Car Future
As electric cars firmly enter the mainstream, more and more debates are opening up about these vehicles and what they can and can’t do, which kinds of
There's a lot wrong with that blog (it's hardly a research paper) and with your interpretation of it.
For starters, the blog opens with this statement:
"In short, regenerative braking is a technology whereby excess energy is recaptured from the standard braking process whereby it is then turned into kinetic energy that is transferred back to the car’s main battery system. The idea first emerged in hybrid cars as a way of extending their overall electric range and allowing for even greater fuel efficiency."
That is a very clear statement that use of regenerative braking enhances fuel efficiency overall.
The blog then goes on to describe coasting:
"In a regular gasoline car, people would use their gathered momentum to keep the car moving forward [my emphasis] — albeit slowing continuously — instead of putting or keeping their foot on the gas pedal. This coasting has long been known as a fuel-saving method, and very useful when driving on highways, or when dealing with very slight forward downhill slopes. Let gravity do some of the work, right?"
This is not an argument that coasting is a more efficient means of slowing a car. It is a description of how average speed can generally be maintained -- i. e., "keep the car moving forward" -- by using coasting intermittently when a car is on a downhill slope or when the car's forward momentum can maintain sufficient speed for brief periods before having to reapply the gas.
Then we get to the areas where the blog is just plain wrong technically. For instance, it reads:
"In short, regenerative braking is a technology whereby excess energy is recaptured from the standard braking process whereby it is then turned into kinetic energy that is transferred back to the car’s main battery system."
No. "Standard braking" is friction braking. The energy that goes into the battery during regenerative braking is not energy from friction braking. It is energy derived from the forward momentum of the vehicle as it slows due to the motors being switched into generator phase.
The blog describes how regeneration is activated thus:
"Releasing the accelerator pedal would simply cause the electric motor to spin in the opposite direction automatically."
Again, a big time no. The motor does not "automatically" start spinning backwards in an EV when you lift off the accelerator pedal. What happens is that the electronic control unit of the car sends a signal to reverse the direction of current flow in the motor, thereby reversing its magnetic field and causing it to function as a generator. The forward momentum of the car keeps the motor spinning in the same direction, but now resisting that direction of travel instead of propelling it. The direction of motor spin does not change during regenerative braking.
Also, the blog describes regenerative braking as "actively creating energy to pass back to the battery."
Once again, no. Regenerative braking does not "create" energy. Nothing since the Big Bang has done that. It recovers energy from the car's forward momentum and converts it into kinetic energy to be stored in the battery.
In short, this blog is a morass of misinformation and misunderstanding of what goes on with regenerative braking.
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that is the theory that porsche went with for the taycan which has minimal regen.
for me I prefer the regen that the lucid has. once mastered it works well. the minimal savings of range is not that important to me.
