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Discussion Starter #1
I've been trying to get my miles per charge up into the 50's. I'm not quite there yet, but yesterday, I drove 48.1 miles on a single charge...my personal best in the almost four weeks I've had my Volt. :) I have a feeling that I could of eked out another mile or two. Oh well...I'll keep trying. :(

This was to/from work: Partial freeway, always driving in "L", no HVAC (nice weather so fan was off), XM is on, headlights on for the last 7-8 miles, I was at 98% driving eff/100% climate eff, & tire pressure 38 psi.

I do take a different route going home to avoid freeways as much as possible in the evening. Once I got to my neighborhood, I drove around a few extra miles to see how far I could go (flat terrain).

Elevation between home and work is about 149m (486 ft) as shown in the altitude maps of my route.

Energy Usage screen:




Elevation profile of route to work:




Elevation profile of route from work:

 

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I've hit 50.1 a couple times on round trips (anything else has too many variables re elevation etc). The tricks are:

It's warm outside, 70-80. Battery likes this a lot, and it seems the rolling resistance is less too (or the oil in the tranny thinner or who knows?). The TMS doesn't regulate to a fine degree, just enough to prevent battery damage.

Tires at 39-40 psi, 1-2 more in the front than the back, by a dial gage. The TPMS isn't that accurate, and is separately temperature sensitive (while my dial gage is not) on top of the tire pressure itself being temp dependent. It's not good enough to tune for best performance by a very long way. Ignore that thing unless for safety reasons only.

Use high and coast on rolling hills when under 40-45 mph. You get more coasting under those conditions than you'd get in regen.
Above about 40-45, wind resistance is the biggie, and I use low and cruise control for that. The CC keeps me from ever going even a little bit faster, which helps since the wind resistance is third power of wind speed, and regen is better then simply losing it all to wind resistance at high speeds. In that case, at least you get some back into the battery.

Avoid sharp cornering, and I mean really - even though this is one great fun handling car. You really scrub off speed. Try this in any car in N and see how much energy (remember E= MV^2) you lose going low Gee vs high Gee on corners. It's sick how much you scrub off that has to be put back from somewhere - costing you range.

Avoid high speeds, period (for hyper-miling anyway). I can really tell the difference in range from 40 to 50 mph, it's a big one. And highway speeds around here are well over 70. It's such a big deal that I can round trip to two towns over if I take the longer back roads and start-stop traffic (lights) every time, but NEVER make it if I take a 4 mile shorter route of which 4-5 miles is highway at 70mph vs start-stop at 30-45mph.

It does actually get better with some time and practice, as both you and the car wear in to fit one another. But you're not doing bad as is - this is for the other guys out here.

I find on some types of terrain that I do much better than the cruise control, which can't know I'm about to hit a sharp corner or top a hill I can coast down for a mile - it always seems to hammer the accelerator at just the wrong time in my terrain. So when I know I'm in a place it will do badly - I turn it off and do it the good old way, with the foot and the human brain knowing what's ahead. GM could fix that with GPS data, but that seems too advanced for them just now.
 

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Almost, but it's doable. I exceeded 50 miles per charge several times in my early build 2012 Volt and that was following all traffic laws etc - no hypermiling etc. Just extra careful to monitor traffic flow, light changes and nice and smooth acceleration, braking and of course NO HVAC.

But I will say that now that we've tasted some fall temps (38 degrees) requiring some heat etc any thoughts of getting 40 miles per charge is out the window. I fully expect to see my range dip into the 20's when we get into the coldest days this winter.

But since my round trip to work is 22 miles my 2012 Volt will still cover that even if the ICE kicks on to provide extra BTU's. That was the criteria I used when I started looking at the Volt last year. Can I get to/from work on the battery.

Keep trying, 50 miles is doable.
 

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How does driving in "L" full time help increase battery range? Is that bad for car in long run?
Along a similar note, I'm curious if driving in "L" while using cruise control is beneficial in any way compared to just driving in 'D' in cruise.
 

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Discussion Starter #7
Tires at 39-40 psi, 1-2 more in the front than the back, by a dial gage. The TPMS isn't that accurate, and is separately temperature sensitive (while my dial gage is not) on top of the tire pressure itself being temp dependent.
Yes, I use an analog hand-held dial gauge.

Avoid sharp cornering...Try this in any car in N and see how much energy (remember E= MV^2) you lose going low Gee vs high Gee on corners. It's sick how much you scrub off that has to be put back from somewhere - costing you range.
I'll play around with corning.

Avoid high speeds, period (for hyper-miling anyway). I can really tell the difference in range from 40 to 50 mph, it's a big one. And highway speeds around here are well over 70. It's such a big deal that I can round trip to two towns over if I take the longer back roads and start-stop traffic (lights) every time, but NEVER make it if I take a 4 mile shorter route of which 4-5 miles is highway at 70mph vs start-stop at 30-45mph.
My return route from work takes me off the freeway. It takes a bit longer to get home, but my range is noticeably better.

It does actually get better with some time and practice, as both you and the car wear in to fit one another. But you're not doing bad as is - this is for the other guys out here.
Thanks!

...GM could fix that with GPS data, but that seems too advanced for them just now.
Then how does the "Eco" route calculation work? Is it just considering non-highway speeds or does it take elevation/altitude profiles into consideration?
 

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Discussion Starter #8
But I will say that now that we've tasted some fall temps (38 degrees) requiring some heat etc any thoughts of getting 40 miles per charge is out the window. I fully expect to see my range dip into the 20's when we get into the coldest days this winter...

Keep trying, 50 miles is doable.
Thanks! Hopefully, nighttime temps won't average below the low-50's this winter here in So Cal. ;)
 

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Discussion Starter #9
Along a similar note, I'm curious if driving in "L" while using cruise control is beneficial in any way compared to just driving in 'D' in cruise.
A big advantage is than when the Frontal Collision Alert system detects that you are closing-in on a vehicle too fast, it'll suspend the cruise control and, since you're in "L", actually slow you down quite rapidly before you even hit the brakes.
 

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I have a 2012 without nav so I know nothing about the eco route stuff - though I do get some strange routing sometimes, it's kind of an adventure now and then. I kind of doubt they'd hook it to the cruise control - liability issues etc, but you could hope. Hey, if I know I'm about to hit a hairpin, or the top of a mile long hill, I'd rather top that hill at near zero mph (low traffic around here lets me get away with that) and then regen all the way down. If I'm about to hit a sharp corner, I turn CC off and regen into it instead so I take it gently.
It really feels stupid when the CC hammers the accelerator just as you almost top that hill or enter that hairpin - scary, even. There are just some things your brain can do better than a computer, given you know more than it does about some things.

The cornering thing was a real surprise to me too - found out by accident. But it's very real, and I've tested a few times. Remember how much energy it takes to squeal tires? Almost doing so is almost as bad. Most auto suspensions don't retain zero toe-in while cornering either, so there's some "scrub" going on as well, at any speed, particularly for tight ones.

I use a little more pressure in the front for two reasons. One is that the edge wear on the tires is more equal that way (less need to rotate tires), and there's more weight there.

L just gives you more regen. L+Sport gives you the tightest cruise control range - less variation from top to bottom speed once set.
But there is a point where the round trip losses on regen are higher than just coasting, and that 40 mph range is about where I stop coasting and start using more regen, it's about where the curves cross.

The weird and counter-intuitive thing is that regen does you more good at highway speeds than at low speeds where coasting works better, due to less percentage of wind loss vs round trip battery/generator loss. Also, the CC helps at high speeds you by NEVER going 5 mph faster, where the wind resistance is really getting fierce vs speed - you might do that on the pedal without thinking about it if traffic speeds up, but the CC will just hold you down in speed. Again, not obvious, but that's how the physics play out. GM is good, but can't cheat physics. There's been a thread on "drafting" but I think the consensus is that you have to be so close you've got a safety problem at that point.

And yes, cold sucks, the heater is wasteful of power, and on top the batteries don't like cold either. I really wish I had a heated garage.
I can, however, heat the car interior with "shore power" using an 800w ceramic heater, or precondition, which only uses 5-8 times as much power in kWH (ouch!)...yet I can still make my main errand loop (27 miles round trip, huge elevation changes) in winter with the heater blasting and no preconditioning. My #2 loop (about 35 miles), nope, not in winter, but I'm working on that with the preheating stuff, going to try that as soon as it gets really cold here (SW VA, not real cold yet).

Wish I had a hold button, that would let me use the ICE upfront for heat, and not use much gasoline at all. It would actually save me money and power, as it takes only about .1 gallon to really heat up the car. I may fake that out with the hood switch to see if that works. It would probably work best if I didn't quite get a full charge first (maintenance mode WILL charge the battery - I've tested that from a 30% to a 70% charge in the driveway, but it messes up the myvolt.com etc numbers), which might not be that hard to arrange this winter with only solar power available...we'll see - last year I never had enough solar in winter, this year I might have enough, having added a few more kw of panels.
 

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When I drive in 'L', and when I get a 1/4 mile or so from a stop and no one is behind me too close, I let off on the accelerator a touch - watching the regen screen - and letting off just enough to get the regen going and then try and hold down on the accelerator enough to keep the car from slowing down too quickly before the stop. Then when I get close enough to do so, let off the accelerator to let the regen brake the car to near stop before applying the brakes fully.

I like seeing the kWh figure go down .1 kWh at stops. Though it probably only puts back about .02 to .04 kWh's at stops in reality and was just at the threshold of that .1 kWh, since it jumps back to that '.1' kWh pretty quickly with accelerating from a stop. But it does add some juice back into the battery over a full EV trip!

So if you have 50 stops, could add up to a full kWh of regen, and a full kWh of energy can get you 4 more miles! Freeway driving kills any hyperdriving capability - unless it's an L.A. freeway and you have stop and go for 20 miles. :)

My personal best is 57.3 miles at night at 80 degrees, with lights on and some eco A/C, but mostly fan only, and XM radio on the whole way. :)
 

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My personal best is 54 miles round trip...and I rarely saw less than 50 when temps were near 75 in VIN C3519.

Take a bicycle mindset...go ride one if you don't remember.

1. Coast in N whenever possible on downslopes or slowing. Plan ahead. I use L For braking to stops.
2. I use D, not L in cruising because its much easier to feather momentum changes.
3. Tires at 40 psi based on dash readout.
4. I keep speed as low as possible, unlike an ICE you are not dealing with engine pumping losses. V^2 is your enemy.
5. Use smooth roads...stay away from rough pavement.

I don't use extreme techniques like drafting, nor do I impede traffic. Also time of day matters...I try to stay out of heavy traffic.
Finally, there are charging games... Preconditioning just before before you leave makes a difference even at 70 degrees because
you "sneak" in a few more watt hours. Finally, Based on work I did on tool batteries before retirement, there probably are differences from one Volt pack to another out of the door, but we don't have integrating loggers to find out.
 

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Yesterday was my first full day of driving my MY2013. My roundtrip was 42.5 miles with estimated 10 miles remaining EV (This drive even had around 20 miles of 65mph highway) I am sure that I could have gotten in the High 50's , had I continued driving till CS. I bought a Prius 4 months ago, and it has taught me in the art of regen driving. If you take it easy on these Volts, they will get you a long way in EV. One thing that I find interesting.....When I took delivery Sat. night, the fully charged range indicated 37 Miles. After driving home 22 miles (only using 13 miles indicated) , and recharging, Sun. morning the estimated was 40. After driving 38 miles on Sun., the estimated was 41. After yesterdays 42.5, today it is up to 43!!! Incredible machine...
 
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