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Discussion Starter · #1 ·
I have a steep downhill for several miles., normally I can pick up 4 -5 miles of range. Yesterday I had zero electric miles and gained zero miles. I was afraid to put it in electric mode at the top in heavy traffic, what would have happened?
 

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There car takes into account that you were regenerating but you would not have been able to put the car back into Normal mode. All that would have happened is that the car would have waited a little longer than usual before cycling the generator back on again.
 

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Not sure what you were afraid of, however if you have zero miles left on the charge and are in Extended Range Mode (ERM) you will not be able to regen and switch back to battery only operation. That is not to say you are regenerating power on the down hill slope, it is just that it will not show up on the gauge. It will be longer period of time before the engine cycles back on as mentioned by the previous post.
 

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Discussion Starter · #4 ·
While I'm sure trying to switch to normal wouldn't have stalled the car I was reluctant to try it in traffic.

Still not clear on this tho, are you saying it is regen-ing in gas mode but just doesn't show it on the GOM?
 

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Still not clear on this tho, are you saying it is regen-ing in gas mode but just doesn't show it on the GOM?
Exactly. Once the Volt uses its allocated electric miles, it will operate like a Prius. Meaning the computer decides how and when to use either energy source.

However, if I remember correctly, you can turn the car on and off and it may let you use those miles gained from regen. (Not sure on that but it's worth a try. You would of course want to park the car first)
 

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Once your vehicle is in extended range mode, any regen that happens gets accounted as gas miles (GM assumes that any potential energy you gained is because of the gasoline engine). In this situation, your car would still show up as running under gas but the gas engine would not turn on until the SoC hits the low point again. However, if you were to stop the car, turn it off, and then start it again, you may see that it running in EV mode.
 

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The regenerated charge shows on the "Power Flow" page on the center screen but not on the GOM on the driver information screen. I have a fairly steep 6 mile long downhill on my drive home. The same 6 mile long grade on my way to work kills my range but I get it back on the way home.

2014 Volt Premium - Safety pkg 1 and 2, Navigation
 

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there really needs to be some means to measure how much actually regenerates during a trip. I want a flat out number, you start with X, you regained Y, and spent a total of Z
 

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I have a steep downhill for several miles., normally I can pick up 4 -5 miles of range. Yesterday I had zero electric miles and gained zero miles. I was afraid to put it in electric mode at the top in heavy traffic, what would have happened?
Note that if your estimated ev range increases 4-5 miles by the time you reach the bottom of a hill, it means your downhill mileage is better than your level terrain mileage, and as long as you keep driving downhill, that improved mileage would allow you to drive further than if you return to driving on level terrain. Since you had no ev range to modify, did you note any change to your gas range estimate?

If you drive far enough to fully deplete your battery, you can’t switch back to Electric Mode because all the useable grid electricity stored in the battery has been used. "Electric Miles" are miles driven using the grid electricity stored in the battery, and any regen obtained while driving in Electric Mode. Once it’s depleted, it’s gone, and you’re in Extended Range Mode until you recharge from the grid.

Regen is potentially possible whenever you are not using the accelerator pedal to maintain or increase speed. Driving Mode doesn’t change the Volt’s ability to create regen. You can drive as far on 1 kWh of regen battery power as you can on 1 kWh of grid battery power.

If you drive in Normal in Electric Mode to the top of a mountain, and fully deplete your battery before you reach the summit, the ICE starts, you’re still in Normal and now you’re in Extended Range Mode. There is no way to switch back to Electric Mode because that requires having useable grid power in the battery, and you now have none.

You then start down the hill... when you reach level terrain again, the battery SOC is now well above the "fully depleted" level because of regen. The ICE is no longer running, not because you switched the driving mode, but because the battery SOC is above the minimum level. You then drive on battery power until the battery SOC drops again to the "fully depleted" level.

This downhill regen may provide you with several miles of battery-powered driving. The ICE is not running, you’re not burning any gas now.

So, are you at this moment driving on "electric power" or not?

Or - because the Gas Icon is still active on the display and Gas Miles keep increasing - do you think your ICE is still running?
 

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Discussion Starter · #10 ·
Note that if your estimated ev range increases 4-5 miles by the time you reach the bottom of a hill, it means your downhill mileage is better than your level terrain mileage, and as long as you keep driving downhill, that improved mileage would allow you to drive further than if you return to driving on level terrain. Since you had no ev range to modify, did you note any change to your gas range estimate?

If you drive far enough to fully deplete your battery, you can’t switch back to Electric Mode because all the useable grid electricity stored in the battery has been used. "Electric Miles" are miles driven using the grid electricity stored in the battery, and any regen obtained while driving in Electric Mode. Once it’s depleted, it’s gone, and you’re in Extended Range Mode until you recharge from the grid.

Regen is potentially possible whenever you are not using the accelerator pedal to maintain or increase speed. Driving Mode doesn’t change the Volt’s ability to create regen. You can drive as far on 1 kWh of regen battery power as you can on 1 kWh of grid battery power.

If you drive in Normal in Electric Mode to the top of a mountain, and fully deplete your battery before you reach the summit, the ICE starts, you’re still in Normal and now you’re in Extended Range Mode. There is no way to switch back to Electric Mode because that requires having useable grid power in the battery, and you now have none.

You then start down the hill... when you reach level terrain again, the battery SOC is now well above the "fully depleted" level because of regen. The ICE is no longer running, not because you switched the driving mode, but because the battery SOC is above the minimum level. You then drive on battery power until the battery SOC drops again to the "fully depleted" level.

This downhill regen may provide you with several miles of battery-powered driving. The ICE is not running, you’re not burning any gas now.

So, are you at this moment driving on "electric power" or not?

Or - because the Gas Icon is still active on the display and Gas Miles keep increasing - do you think your ICE is still running?
Thanks, that's deep.

So what you are saying is the computer (s) are smarter than me?

Them's fighting words...
 

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Thanks, that's deep.

So what you are saying is the computer (s) are smarter than me?

Them's fighting words...
Once you drive a Volt for a while, all these little data points become less important. I've been driving Volt/ELR for four years and don't worry about stats any more. I plug in every night and fill the gas tank once a month. The only stats I keep are TCO dollars in an iPhone app.

Some are gamers, I am no longer a Volt gamer.
 

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Once the battery is depleted, you can not use normal mode. To use the regen miles, just turn off car, restart and normal mode is now available :)
 

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With our 2016 Volt I leave 15 miles of electric range left and drive in Hold. When climbing hills, sea level to 500+ feet in elevation, I place in hold, the motor shuts off and regen begins. I have 2 hills to climb when I arrive at the bottom of the 2nd the range indicator on electric is now 23 miles. I then place in hold about 15 miles or so from home and usually arrive with 2-4 miles of range left, the third and last hill I normally climb and decend in normal electric mode on the last leg home.

Voltstats.net usually counts these extra miles on those 2 hills as electric even though they were generated by the gas motor climbing the hill. The Volt gauge readout is more accurate. According to Voltstats the last trip the gauge read 64.5 miles on electric (still had 2 miles left at arrival home with 14.1 KWH used), Voltstats.net stated 68 miles on electric.
 

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Exactly. Once the Volt uses its allocated electric miles, it will operate like a Prius. Meaning the computer decides how and when to use either energy source.

This is one of the tricks in getting super high MPGcs number. Climb the hill in electric, then switch to gas in the downhill, your MPGcs will be well over the 42 mpg EPA rating.
 

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This is one of the tricks in getting super high MPGcs number. Climb the hill in electric, then switch to gas in the downhill, your MPGcs will be well over the 42 mpg EPA rating.
Or for a different thrill, remain in Hold mode as you drive down a long hill. When you reach level terrain, stop and turn your Volt off and back on again. By turning the car off and back on, the computer will now record as Electric Miles the miles you drive on this regen-while-in-Hold-mode battery power!

Of course, it’s not regen-during-Electric-Mode battery power driving, so it doesn’t factor into the net grid power consumed calculations displayed on the usage screen. While you’re driving on this battery power, your kWh Used number doesn’t change.

Wow, more ev miles with no increase in consumption, a big increase in ev miles/kWh!

And the same number of miles subtracted from your total gas miles/gas used, for a reduction in your MPGcs gas mileage!
 

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Having 15 miles of electric in hold is insurance for those unexpected highways that turn into parking lots sometimes in the Portland Oregon area. Also when your heading home and a few miles out I just place in normal (electric) mode and arrive home with 0 or a couple of electric miles left.
 
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