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Discussion Starter · #1 · (Edited)
I've been meaning to go up Mount Washington for the last 40 years, MountainVolt's post last week was the kick that made me do it. Went up Saturday, it was 65 degrees up top which is great for Mount Washington the record for June is 71. I drove there in Hold so that I had an almost full battery, went up in normal and down in L mode with the regen paddle. I hardly touched the brake peddle so the wheels were ice cold at the bottom. Energy consumption on the way up was mostly in the low 20KW, peaking at 33KW. On the way down the regen peaked at 14KW. I used a total of 9.4KWh on the way up, got back 4.9KWh on the way down. After Mount Washington we drove to the Mount Washington Hotel for dinner and then home. For the total trip I did 54.3 miles on battery using 14.2KWh (107 MPGe) and 309 miles on gas using 6.57 gallons (47.3 MPG). The regen returned 52% of the energy.

My only complaint is that the regen braking occasionally let go necessitating the use of the brake peddle, but that was rare and so I hardly used the brake peddle at all.

Start
4 miles, 1.2 KW used
guess_o_meter 65, 90.6 MPGe

Top
11.4 miles, 10.6 KW used
guess_o_meter 7. MPGe 30.8 MPGe

Bottom
18.9 miles, 5.7 KW used
guess_o_meter 47, MPGe 92.7

End of Trip
54.1 miles, 14.2 KW
guess_o_meter 0

------
Climb used 9.4 KW
Descent returned 4.9 KW

Regen returned 52%
 

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Regen may be disabled if traction control detects rough road or loss of traction. It may also be disabled if battery and regent buffer are full, or if battery is not in optimal temp range.
 

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Thanks for your review. Must have been a fun trip. Its nice to get regen when other regular vehicles just wear out their brakes on the way down. Also over 47 mpg just on gas is better than most of all the eco boxes would have done. You beat the EPA figures of 53 on electric and 42 mpg on gas as well. I live on the other side of the country, and I plan on doing a Hurricane Ridge Run in Port Angeles, Washington, Olympic National Park, with our 2016 Volt when we are up there visiting family. I'm not sure if I could make the entire climb with electric...
 

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Discussion Starter · #4 ·
Regen may be disabled if traction control detects rough road or loss of traction. It may also be disabled if battery and regent buffer are full, or if battery is not in optimal temp range.
There were some rough patches, battery was pretty well drained by the drive up so that wasn't it.
 

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There were some rough patches, battery was pretty well drained by the drive up so that wasn't it.
I experience the same thing under heavy braking in a particular part of my commute where there is a slight bump in the road. This is normal, as designed, though it can send your gut sinking as you get surprised by it. When this happens you might be able to catch a glimpse of a yellow traction icon on the dash flashing a few seconds after it happens. It'mormal, nothing to worry about with the car itself, but if you see it happening more and more, that's a sign you might need to check your tires. New tires will help, but not completely eliminate this "feature".

I have fond memories of mt. Washington. We went there with a rental after moving my daughter into her dorm then blowing off orientation week 5 years ago. We were lucky enough to catch pictures and selfies in front of twin double rainbows (two rainbows that each cycled through the color spectrum twice, not sure what the scientific term is).

We also stumbled onto the most wonderful bakery in horthern Vermont. Rainbow Sweets Bakery in Marshfield, VT is a must visit place, before the owner and proprietor gets too old and retires. You must get the Johnny Depp Balls. We spend $85 for a family of 4, but had try one of nearly everything because it was so delicious. The owner also tells stories of how he grew up neighbors with Ben and Jerry, another place to visit, but the urgency isn't so great as they continue to operate with the next Generation kids.

https://www.facebook.com/Rainbow-Sweets-Bakery-118669924836893/
 

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Instead of the Mt Washington Hotel, stop at the Woodstock Inn and Brewery for a meal. They have a free charging station outside.
 

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Discussion Starter · #7 ·
Thanks for your review. Must have been a fun trip. Its nice to get regen when other regular vehicles just wear out their brakes on the way down. Also over 47 mpg just on gas is better than most of all the eco boxes would have done. You beat the EPA figures of 53 on electric and 42 mpg on gas as well. I live on the other side of the country, and I plan on doing a Hurricane Ridge Run in Port Angeles, Washington, Olympic National Park, with our 2016 Volt when we are up there visiting family. I'm not sure if I could make the entire climb with electric...
I usually get 47-48MPG on gas on the highway in summer so that number was to be expected. What was unexpected was that I ended up with 54 total miles on the battery even though I did the Mt Washington climb.

Please keep track of your numbers when you do the Olympics. I've never driven then but I did hike the Olympics in 1969 when I was a kid.

If anyone is in Silicon Valley have you done the drive from San Jose to the Lick Observatory in a Volt? I've done that drive a number of times in an ICE car in the last century and as I recall it's much more difficult than the Mt Washington drive but maybe that was psychological because of the switchbacks which we don't have in the East.
 

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I usually get 47-48MPG on gas on the highway in summer so that number was to be expected. What was unexpected was that I ended up with 54 total miles on the battery even though I did the Mt Washington climb.

Please keep track of your numbers when you do the Olympics. I've never driven then but I did hike the Olympics in 1969 when I was a kid.

If anyone is in Silicon Valley have you done the drive from San Jose to the Lick Observatory in a Volt? I've done that drive a number of times in an ICE car in the last century and as I recall it's much more difficult than the Mt Washington drive but maybe that was psychological because of the switchbacks which we don't have in the East.
I haven't done it in the Volt yet, but it might be fun. Back side of Mt Hamilton is great sports car territory. Tons of twisties.

I have been all over Highway 9, Skyline, Page Mill, La Honda, etc though. In fact just did some of it this morning. (Went with one of my sons for a Fathers Day breakfast that "couldn't be beat" at Alices. :) ) The Volt does great up and down Highway 9. On the way down I used "L" all the way, hitting the regen paddle if I was about to enter curves a little too fast. Almost never needed to touch the brake pedal.
 

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I am tempted to try pikes peak in the volt. I would guess it won't make the top on battery since its 20 miles or so. The race is only 11 miles but it starts about half way up. I think I could charge it most of the way back up on the way down.

Last time I drove it, we were in a SUV with an automatic. We got the brakes over 350deg even using low gear. The back brakes were cool suggesting that the brake balance was way off or set for panic stops only. I have also run across a minivan with the hub caps melted off the wheels.
 

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Seems like you had a delightful trip!

From MountainVolt’s previous description of the journey, it sounds as if descending the mountain involves careful attention to driving, rather than just putting the car into L and cruise control and letting braking regen alone maintain the appropriate speed. The paddle must have come in handy!

Of course, the source of your Volt’s kinetic energy that enabled you to accumulate 4.9 kWh of regen energy was gravity, not previously consumed battery power, so you were capturing, not recapturing it. Still, I would think you drew very little energy from the battery during the descent, so the drop in kWh Used from 10.6 to 5.7 would approximate the amount of regen going back into the battery.

This leads me to speculate that the regen efficiency during the ascent was very low. Did you obtain much braking regen on the way up, or was gravity a sufficient force to slow down and stop the car when needed? In both directions the kWh Used is a net figure. The descent doesn’t usually include much battery consumption in the total. The ascent might not include much regen.

Perhaps what is remarkable is that the 54.1 Electric Miles you achieved on a full charge is very close to the window sticker rating of 53 miles of range, even though a big chunk of your electric miles involved driving up a mountain and back down again. Perhaps gravity-derived downhill regen counterbalances the extra battery energy it takes to ascend, so that, generally speaking, driving on battery power across flat terrain produces about the same AER as driving up and down hills.
 

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I am tempted to try pikes peak in the volt. I would guess it won't make the top on battery since its 20 miles or so. The race is only 11 miles but it starts about half way up. I think I could charge it most of the way back up on the way down.

Last time I drove it, we were in a SUV with an automatic. We got the brakes over 350deg even using low gear. The back brakes were cool suggesting that the brake balance was way off or set for panic stops only. I have also run across a minivan with the hub caps melted off the wheels.
All vehicles use the front brakes much more than the rears. Have you ever noticed that the brake pads on the fronts are usually much bigger than the rears? When braking, all of your weight shifts to the front so if you made all 4 brake evenly, the rears will skid early in the braking cycle, thus contributing to instability.

The opposite is true when you peel out. With a race car, the rear wheels get you moving, the weight shifts to the back, and that helps give you more traction. With a FWD vehicle, as you take off, the rear wheels get all the weight and the fronts become lighter, thus losing traction. Most everyone except ricer boys much prefer a RWD vehicle over a FWD. Alas, with the arrival of the EVO (r.i.p) and Subaru WRXti they added AWD greatness and turbos to what were previously econoboxes. And I guess Audi has had their Quattro for a few decades too.
 

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Discussion Starter · #13 ·
Instead of the Mt Washington Hotel, stop at the Woodstock Inn and Brewery for a meal. They have a free charging station outside.
Thanks we've been looking for an alternative, our meal at the Mt Washington Hotel was terrible.
 

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Discussion Starter · #14 ·
Seems like you had a delightful trip!

From MountainVolt’s previous description of the journey, it sounds as if descending the mountain involves careful attention to driving, rather than just putting the car into L and cruise control and letting braking regen alone maintain the appropriate speed. The paddle must have come in handy!

Of course, the source of your Volt’s kinetic energy that enabled you to accumulate 4.9 kWh of regen energy was gravity, not previously consumed battery power, so you were capturing, not recapturing it. Still, I would think you drew very little energy from the battery during the descent, so the drop in kWh Used from 10.6 to 5.7 would approximate the amount of regen going back into the battery.

This leads me to speculate that the regen efficiency during the ascent was very low. Did you obtain much braking regen on the way up, or was gravity a sufficient force to slow down and stop the car when needed? In both directions the kWh Used is a net figure. The descent doesn’t usually include much battery consumption in the total. The ascent might not include much regen.

Perhaps what is remarkable is that the 54.1 Electric Miles you achieved on a full charge is very close to the window sticker rating of 53 miles of range, even though a big chunk of your electric miles involved driving up a mountain and back down again. Perhaps gravity-derived downhill regen counterbalances the extra battery energy it takes to ascend, so that, generally speaking, driving on battery power across flat terrain produces about the same AER as driving up and down hills.
Gravity is the storage medium, from a physics perspective it's no different than the battery. You start out with the potential energy in the battery, as you climb you are converting the battery's energy into gravitational energy (minus the losses) so at the top of the mountain your potential energy is stored as height times weight,

PE = kg x 9.8 m/s2 x m = joules

When you drive down the mountain the gravitational energy is converted back into battery energy (minus losses) so technically you are recapturing the energy that you used to climb the mountain.
 

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...
Of course, the source of your Volt’s kinetic energy that enabled you to accumulate 4.9 kWh of regen energy was gravity, not previously consumed battery power, so you were capturing, not recapturing it. Still, I would think you drew very little energy from the battery during the descent, so the drop in kWh Used from 10.6 to 5.7 would approximate the amount of regen going back into the battery.
That's an odd way to look at physics... it was precisely the consumed battery energy that allowed the Volt to climb to a higher altitude, thus raising the car's potential energy (mgh). So yes, regen on the way back down is recapturing expended battery energy. You're just converting battery chemical energy into gravitational potential energy and back.

Edit: bjrosen beat me to it, that'll teach me to take a coffee break :p
 

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All vehicles use the front brakes much more than the rears. Have you ever noticed that the brake pads on the fronts are usually much bigger than the rears? When braking, all of your weight shifts to the front so if you made all 4 brake evenly, the rears will skid early in the braking cycle, thus contributing to instability.

The opposite is true when you peel out. With a race car, the rear wheels get you moving, the weight shifts to the back, and that helps give you more traction. With a FWD vehicle, as you take off, the rear wheels get all the weight and the fronts become lighter, thus losing traction. Most everyone except ricer boys much prefer a RWD vehicle over a FWD. Alas, with the arrival of the EVO (r.i.p) and Subaru WRXti they added AWD greatness and turbos to what were previously econoboxes. And I guess Audi has had their Quattro for a few decades too.

I am well aware of weight transfer effecting which wheels do the braking. When I road raced motorcycles it was 100% front braking as the rear wheel was often in the air, but at slow speeds like coming down pikes peak the rear should be doing some work and based on the temps it was not. So that suggests that the brake bias was set heavily to the front and did not adjust based on weight transfer or lack of transfer. So the brakes were not working as efficiently as possible. I know my old Toyota trucks had variable brake bias as you can see the mechanism under the bed. As I don't normally drive an automatic it was an interesting observation on the cheapness of the modern car.
 

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I haven't done it in the Volt yet, but it might be fun. Back side of Mt Hamilton is great sports car territory. Tons of twisties.

I have been all over Highway 9, Skyline, Page Mill, La Honda, etc though. In fact just did some of it this morning. (Went with one of my sons for a Fathers Day breakfast that "couldn't be beat" at Alices. :) ) The Volt does great up and down Highway 9. On the way down I used "L" all the way, hitting the regen paddle if I was about to enter curves a little too fast. Almost never needed to touch the brake pedal.
Reminder: Brake pedal does EXACTLY the same thing as L, as the paddle, just more flexibly.
 

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Reminder: Brake pedal does EXACTLY the same thing as L, as the paddle, just more flexibly.
But then you have to move your foot. Paddle allows saving precious milliseconds when diving into a curve or hairpin. Between the instant torque, the low CG, and the regen braking, the Volt is really brilliant on the mountain twisties we have around here.

Now that bjrosen has mentioned it, I guess I am going to have to see how it does on Mt Hamilton. It has been some years since I've been up to the observatory. Lots of twisties going up to it - including a really steep climb just before you get there. The back (east) side of the mountain is also a lot of fun. However I am going to have to think about charging opportunities so that I don't have to use gas (horrors!) and mess up my voltstats.
 

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We had two Volt so far, the first a 2014, which we put on well over 40,000 miles. Traded it in for a 2016 Volt in July 2016. I nearly always use L and with the 2016 L and the paddle for one foot driving. To me its more comfortable. Than having to lift your foot for the brake. I guess the Volt has really made me a lazy driver.....
 

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Reminder: Brake pedal does EXACTLY the same thing as L, as the paddle, just more flexibly.
I would tend to disagree. If you are abrupt with the brake pedal, the Volt WILL use the brake pads. If you use the paddle, the Volt WILL NOT use pads.
 
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