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Discussion Starter · #1 · (Edited)
I've been reading the great posts here for a while but just got around to registering. This is a great site. I've enjoyed reading the posts from those who have their Volts. I don't (yet) own a Volt but plan to soon.

One topic that I haven't seen a lot of posts about is driving strategies that can be used to extend both EV range and boost MPG in CS mode. I'm not talking about the obvious (driving at 55 mph in the right lane) or limiting cabin heat. One example is I've always found limiting off the line acceleration can have huge benefits. In my Hybrid, there are many shifting strategies to boost the battery SOC, and thus extend EV range, such as shifting into and out of low at certain times, braking a little late to maximize regenerative braking, etc.

Are there any interesting driving strategies that Volt owners have found (other than limiting cabin heat)?
 

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Probably the best one for the Volt is to use the L gear as much as possible in town or hilly driving. It sounds wrong to use a "Low" gear for better economy, but the Low gear in the Volt is NOT really a lower gear, it just adds extra regenerative light braking whenever you take your foot off the accelerator, restoring some power back into the battery, and it "feels" like you are in a Low gear because of that. Acceleration remains the same as whichever of the three driving modes you are currently in, (normal, sport, or mountain)

I haven't received my Volt yet so this is just by word of mouth of course, but I am hopefully going to be using it myself in about another week. I hope to have my 240 volt charger installed fairly soon too. Demo Madness, here I come, ready or not!

Jerry, still waiting for #536. PLEASE HURRY!!!
 

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The regen works very well as demonstrated by a trip down a mountain that went from 2600 ft to about 200 in a distance of 4 miles. I started the decent with 6 miles of batt remaining and used normal and low. when I got to the bottom I had 26 miles of batt remaining so as you see it just works.
Roy
Volt #272
 

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I wonder ... Do you think that was all regen or do you think the car recognized favorable mileage while going down hill and simply raised its estimates as if the rest of your trip would be that easy?
 

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I just don't know but it is a very steep grade --I think almost 8%. I don't think that the computer would give much change in that short distance but it would be an interesting question for a Volt engineer.

Roy
#272
 

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Likely that much regen is not possible...so I agree, it just changed the estimated distance based more on the lack of power used, rather than power gained via regen.
I have found as I descend my three mile hill, I generally regen about 3 miles of distance. But I like to use drive to pick up speed down the hill, and shift to L the second half, mostly because I can't keep up with traffic using only L the whole way. Also, using D, I can hit a sweet spot with the pedal that keeps regen going while still keeping a steady 55 down the hill and not losing speed.
 

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The regen works very well as demonstrated by a trip down a mountain that went from 2600 ft to about 200 in a distance of 4 miles. I started the decent with 6 miles of batt remaining and used normal and low. when I got to the bottom I had 26 miles of batt remaining so as you see it just works.
Roy
Volt #272
To echo totolos: Did the green bars indicating how much battery you had left go back up, or just the numbers indicating the range remaining?
 

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The bars showed higher pack charge and I drove it for quite a while after and it acted just as if I had charged it from an outlet. The charge did not drop faster than any regular charge. I had it in low most of the way down and I had a speed of 27 MPH in this config but once in a while would put it in drive to get some speed up. If any of you know the Palm Springs area it is from the tram lower station to Palm Springs Visitor Hut. I had put it in mountain mode about 10-15 miles from the mountain with 23 miles left on batt and when put in mountain it went immediatly to 13 miles left on batt. The generator turned on before I started up and I had good acceleration going up and when put in normal at the top there was 6 miles left on batt and 26 at the bottom.

Roy
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No tricks, just physics

There's no tricks, just physics.

Force = mass X acceleration. In the Volt, the force required to move the vehicle comes from the battery (or ICE). Since the mass is fixed, the only way to lower the force required to move the vehicle is decrease your acceleration.

At steady state speeds, the Volt has to overcome the force of Drag. Drag = 1/2 X Air Density X Velocity^2 X Car's Cross Sectional Area X Coefficient of Drag (Cd).

Since Air Density is basically fixed, as is the frontal area of the Volt and it's Coefficient of Drag, the only way reduce Drag is to slow down, as drag is a function of the square of your speed.

Lastly, since the Volt is electrically driven, turn off all assessories that consume electric power, as that power must be supplied by the battery or the ICE.

So to maximize EV range (or your MPG): accelerate as slow as you can (without causing road rage); drive the speed limit; and turn everything off.

Cheers!
 

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At steady state speeds, the Volt has to overcome the force of Drag. Drag = 1/2 X Air Density X Velocity^2 X Car's Cross Sectional Area X Coefficient of Drag (Cd).
There's also rolling resistance, which I don't know how to estimate or even express.

But yes to your point that speed kills range. Having driven a Volt for several hundred miles at 82 MPH now (CS mode), MPG drops into the low 30s when I do that. MPGs at 65 appear in short tests appear to be in the low 40s.
 

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The batteries are never ‘technically ‘ depleted. I have gone several days without plugging-in, yet the Volt (through regen) will keep the batteries at a ‘soc’ to allow you to drive for what seems like infinite miles in stop- n-go traffic in mostly electric mode (under 25 mph), with just occasional and very minimal power from the ICE. Since I’m not really paying to charge the car using electricity, and ICE isn’t running that often (saving on gas), the whole experience feels kind of weird, in a good way.
 

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The best thing you can do to minimize rolling resistance is make sure you keep your tires properly inflated, which is 35 PSI all around on the Volt.
 

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Has anyone experimented with over inflating their tires yet? With my 2 Prii, I have always kept the tires at least 4-5 PSI above what was suggested by Toyota (but well under the max PSI for the tire). It's fairly common practice among Prius owners, at least on the Prius boards. I found about a 2-3 MPG difference. I'm not sure I would recommend over inflation for those that have to deal with snow/ice/etc. But for SoCal driving, I have noticed no performance issues with my Prii (still waiting on my Volt).
 

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Has anyone experimented with over inflating their tires yet? With my 2 Prii, I have always kept the tires at least 4-5 PSI above what was suggested by Toyota (but well under the max PSI for the tire). It's fairly common practice among Prius owners, at least on the Prius boards. I found about a 2-3 MPG difference. I'm not sure I would recommend over inflation for those that have to deal with snow/ice/etc. But for SoCal driving, I have noticed no performance issues with my Prii (still waiting on my Volt).
It's very possible you could get a small increase if MPG but you will pay in reduced tire life as your tires will wear out in the center first with over inflation. Sometimes this is better as many people don't watch pressure closely and they drop below correct pressure before checking again.
 

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Actually air density is not fixed and depends on temperature and altitude. Ask a pilot that has to take off at a high altitude and very hot day.

P
 

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It's very possible you could get a small increase if MPG but you will pay in reduced tire life as your tires will wear out in the center first with over inflation. Sometimes this is better as many people don't watch pressure closely and they drop below correct pressure before checking again.
Possibly...the tire pressure recommendation is a compromise from the factory for comfort, tire life, and traction performance. In my 96 Impala SS I would increase the tire pressure to 42 front 40 rear for dry traction performance and saw no increase wear in the center. Factory is 30psi! In my next car, the xB with factory psi of 29, I did the same but saw increase center tire wear and dropped it to 37psi.

I've increased the tire pressure on the Volt to 38psi to see how much tire wear I get. It's not much harsher, and performs a little better in dry conditions. Though with tire pressure the returns seem to diminish above 35ish PSI.

If it was a typical car I would say increasing the stock psi by 5 is of no concern for tire wear. But I'm sure they push the tire pressure closer to the limit with the volt which is why I just did it by 3psi.
 
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