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Anyone know a way to track total regen'd miles per trip. Mygreenvolt only seems to show the percentage regen (% of what?) The only rough way I can think of is to start with a full charge, then completely discharge the battery, use hold mode uphill, then any excess over your normal range would be total regen for that trip
 

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I'm surprised some of your fellow regen fanatics haven't responded here. To me, the main purpose of regen is to save your brake pads. I try to drive efficiently and try to avoid braking (regen) actions. My regen is minimal.
 

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To me, the main purpose of regen is to save your brake pads. I try to drive efficiently and try to avoid braking (regen) actions.
The main purpose of regen is to give you back most of the energy it took to get your car moving away from a stop - If you use the brakes (like most ICE cars must) you're wasting that kinetic energy and will have to use more energy to get moving again. This is why EV's get better around town mileage than on the freeway and ICE's are the opposite

Don
 

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So you never decelerate?
Deceleration is only needed if you are going too fast. Ideally, you should only expend enough energy to coast to a stop at your destination. Sort of like playing shuffleboard, shuffleboard pucks don't have brakes. Of course, doing this with somebody behind you is not advised.
 

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The main purpose of regen is to give you back most of the energy it took to get your car moving
Energy is always lost in conversions, it's a law of physics. I can't give you any data, but I doubt you get most of the energy back. Maybe this is why the car doesn't keep stats on regen, most people would end up being very disappointed.
 

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Stop light are always green? The car in front of you never slow down faster than you? It is safe to drive significantly slower than the flow of traffic?

I agree driving slowly save energy. I tend to do that myself. But unavoidably one has to decelerate due to practical road circumstances. Regenerative braking makes that much more efficient. It does save energy, in addition to prolonging the brake pads.

-TL

Sent from my SM-G930T using Tapatalk
 

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Energy is always lost in conversions, it's a law of physics. I can't give you any data, but I doubt you get most of the energy back. Maybe this is why the car doesn't keep stats on regen, most people would end up being very disappointed.
I don't have proving data either, but have read that as much as 75% of kinetic energy is reclaimed. It think that is pretty variable, depending upon technique, geography etc. But I do believe it is substantial.
 

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I'm not talking about driving slower. If you leave a greater distance between you and the car in front of you, you can anticipate slowing down easier. Also, looking ahead of you and monitoring the state of traffic lights and traffic in general, you can also avoid unnecessary braking.

Hypermiling in traffic is a no-no. But there are many safe techniques to avoid braking.
 

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I don't have proving data either, but have read that as much as 75% of kinetic energy is reclaimed
Where did you read that? On the internet? It must be true then.
I believe I've read it here on this forum. Cant tell you which thread, still learning my way around...
And have only put 1k on my volt at this point. I think much of the findings are deductions based on one's stats on voltstats. I think it would be difficult to be accurate with the available data, but even my short experience proves out regenerating gains in metro driving vs just getting on the highway at 55mph for a full battery cycle. Metro being the Illinois tollways during variable speed commutes.
 

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I'm not talking about driving slower. If you leave a greater distance between you and the car in front of you, you can anticipate slowing down easier. Also, looking ahead of you and monitoring the state of traffic lights and traffic in general, you can also avoid unnecessary braking.

Hypermiling in traffic is a no-no. But there are many safe techniques to avoid braking.
@caskConditionedAle: I agree with you.
@TangoLima: Watch and see how many Kw it takes & for how long to accelerate, then see how much using regen returns. Certainly is not 75% unless going downhill. I used to think regen was fantastic, now I think with careful & thoughtful driving, one can obtain much better mileage than "Exclusively" using regen & L. Not saying I don't use regen, but if driving for mileage I try not to. I'm still learning. My best so far is 1Le/100Km possibly ~ 235 Mi/ US Gal.
 

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Ok I may have misunderstood. Some seem to claim regenerative braking would make no difference in efficiency, if one apply "proper techniques". I can't agree to that. I say regenerative braking, in addition to the same proper driving techniques, is always better.

-TL

Sent from my SM-G930T using Tapatalk
 

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@caskConditionedAle: I agree with you.
@TangoLima: Watch and see how many Kw it takes & for how long to accelerate, then see how much using regen returns. Certainly is not 75% unless going downhill. I used to think regen was fantastic, now I think with careful & thoughtful driving, one can obtain much better mileage than "Exclusively" using regen & L. Not saying I don't use regen, but if driving for mileage I try not to. I'm still learning. My best so far is 1Le/100Km possibly ~ 235 Mi/ US Gal.
Hold the phone. Went out to mow and clear my head from a bad day at the office...and the post. The 75% number came from charger efficiency...not regen efficiency! Sorry.

I think it would take a lot of sophisticated equipment to understand what all the ancillary power draws are, as a percentage over any given moments in time. Since those non-propelling and also non-regenn-ing activities are an energy "cost of doing business" all the time, you can't just look at the Kw gauge and make assumptions.

The positive number is overstated (more positive) since it represents propulsion + all other power draws.
The negative number is overstated (less negative) since it represents regen (a negative number) + all other power draws (a positive number).
 

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Anyone know a way to track total regen'd miles per trip. Mygreenvolt only seems to show the percentage regen (% of what?) The only rough way I can think of is to start with a full charge, then completely discharge the battery, use hold mode uphill, then any excess over your normal range would be total regen for that trip
The Nissan Leaf’s Carwings app could (perhaps still can) do for that car what you seek for your Volt: it presents "Energy Economy" trip data showing the power consumed for each trip (trip = car on to car off, i.e., home to grocery, grocery to library, etc.) as a sum of the battery kWh used (positive) and the regeneration obtained during the trip (negative), enabling one to calculate miles/kWh Used numbers. I don’t think any Volt app or display provides similar data. An extended range vehicle is a difficult creature to evaluate. You don’t need to be running on battery power in order to regen, so the distance you travel on regen power is not all Electric miles/km.

The main purpose of regen is to slow the car down, just like the friction brakes do. Prolonging the life of the brake pads and drums is a bonus. Putting some charge back into the battery is a bonus, too. GM’s implementation of this feature in the Volt allows you to use the brake pedal to engage the regenerative braking system. Friction braking is "blended in" if the pressure you put on the pedal is asking for more "stopping power" than regen can deliver, such as for a panic stop, or for stopping the car below ~5 mph.

The "bonus" is that level terrain regen recaptures some of the energy used to accelerate the car to the current speed. Energy used to maintain speed is irrecoverable.

Accelerating from one speed (or from a standing start) up to traffic flow speed requires the use of a certain amount of energy. Accelerating back up to the same traffic flow speed from the same starting point requires the use of the same amount of energy. Normal driving conditions require you to slow down or to stop from time to time (e.g., the traffic light ahead changes to red) and then accelerate back up to speed.

With friction brakes, each time traffic conditions slow you down or bring you to a stop, and you later accelerate back up to speed, the amount of energy used for each acceleration episode may remain the same. Because regenerative brakes capture some of that energy previously used to accelerate, each repetition of "slow down, speed up" reduces the "per episode average" amount of energy used for accelerating back up to speed. Reducing that total amount of energy used to accelerate the car leaves more for maintaining your traffic flow speed.

If you minimize regen by minimizing the number of times you need to "accelerate back up to speed" and minimizing the amount you decelerate before the light changes (by starting your coast sooner in D to stretch out coasting time, giving the light more time to change) you keep even more of the original amount of grid power for use in maintaining speed...
 

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I used the MyGreenVolt app this morning and it said I regenerated .4kWh on my 6.4 mile trip. My car's display said it only used 1 kWh for my trip, but if I regenerated .4 kWh it actually took 1.4 kWh to travel the 6.4 miles. That makes my total regen percentage at 28% (.4/1.4) of total power consumed. The app confirmed this number. My car is a 2012 in case anyone was wondering.

Unless you are coasting down a mountain, I can't see any way for the Volt to regen 75% of its energy consumption.
 

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I used the MyGreenVolt app this morning and it said I regenerated .4kWh on my 6.4 mile trip. My car's display said it only used 1 kWh for my trip, but if I regenerated .4 kWh it actually took 1.4 kWh to travel the 6.4 miles. That makes my total regen percentage at 28% (.4/1.4) of total power consumed. The app confirmed this number. My car is a 2012 in case anyone was wondering.

Unless you are coasting down a mountain, I can't see any way for the Volt to regen 75% of its energy consumption.
Level terrain regen captures some of the energy previously used to accelerate the car to the current speed. Energy used to maintain speed is irrecoverable.

You created 0.4 kWh of regen, but the question is, how much of the total energy used was used to accelerate your Volt, and how much was used to maintain speed?

You used 1.4 kWh to travel 6.4 miles. Let’s break that down: If it took 0.87 kWh to maintain speed, then 0.53 kWh of it would have been used to accelerate the car. If those were the numbers, regen recaptured 0.4/0.53 of the kWh used to accelerate the car, or ~75%.

I don’t know of any reliable method of breaking down energy used to accelerate vs energy used to maintain speed. I suppose one could use one of the apps to note the drop in raw battery soc when accelerating from a standing start to a given speed, then immediately take the foot off the accelerator and note the increase in SOC as the car regenned to a stop, and use math to calculate the amount of acceleration energy and the amount of regen recovered energy.
 

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Energy is always lost in conversions, it's a law of physics. I can't give you any data, but I doubt you get most of the energy back. Maybe this is why the car doesn't keep stats on regen, most people would end up being very disappointed.
Based on what I've seen my 2017 Volt is somewhere between 80 and 90% efficient on recovering the extra energy needed to accelerate (or climb, which is also acceleration).
 
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