I'm Back with a VOLT!

[ksa8907]

In sub 50F weather, winter blend gas, 87 octane and not premium... i see roughly 33-36 mpg at 70mph in charge sustain mode.

Not great at all.

On the other hand, on the 1 or two days it has been 60F+ outside with light winds, driven at 60mph, again with regular 87 octane winter blend I have seen 45mpg over about 30 miles of straight highway. The car will "pulse and glide" with the generator. It drops to its lowest output and if it still overcharges the battery, it will shut down and run on battery until the pack drops below a specified threshold.

Gas only mpg will most likely be lower than a prius in every driving scenario, but the fact at it also has roughly 9.5 kwh of EV range means it is on par with the prius in most situations.

[cowmeat]

You'll see it does that at stop lights when you coast to a stop. It's one of the things I used to like about my G1 Insight too.
The ICE will run for a couple of seconds and then shut off as you're slowing, and as you take off you'll be on EV power until the ICE kicks back in, so as you're getting up to speed you aren't burning gas

When I'm coming up to a light I know will cause me to stop I coast down in "D" most of the way then switch back and forth between "L" and "D" to get the longest coasting distance and most regen possible. If I time it well I never hit the brakes or come to a full stop
Before climbing a hill I slowly gain speed and then bleed it off as I come up the front side. As I crest the hill I throw it in "N", and down the back side of the hill I'm in neutral picking up speed until the hill bottoms out.

[Ecky]

I wonder why the Volt gets "such low" highway mpg. Did GM go with a relatively inefficient powerplant? Is it the tires? How efficient is the 1.4? I seem to recall reading that the related hybrids (Malibu?) had higher combined ratings on gasoline.

[ksa8907]

Originally Posted by cowmeat

You'll see it does that at stop lights when you coast to a stop. It's one of the things I used to like about my G1 Insight too.
The ICE will run for a couple of seconds and then shut off as you're slowing, and as you take off you'll be on EV power until the ICE kicks back in, so as you're getting up to speed you aren't burning gas.

Yes, but I have seen it do this on the highway with the cruise control set. When the battery gets above it's CS threshold it shuts the engine off and cycles back and forth between ICE and battery depending on SOC.

Again, I believe this is a rare occurrence. I don't recall if I was drafting at the time or not.

[hayden55]

Originally Posted by Ecky

I wonder why the Volt gets "such low" highway mpg. Did GM go with a relatively inefficient powerplant? Is it the tires? How efficient is the 1.4? I seem to recall reading that the related hybrids (Malibu?) had higher combined ratings on gasoline.

Thermal efficiency is only 10% less than the Prius (35 vs 38.5). For the most part its because:
Drag area is: 23.7 x 0.285 - 6.7545sqft
Prius DA: 23.4 x 0.25 - 5.85sqft.
So the Volt has on top of 10% worse thermal efficiency, it has 15.5% more drag, and weighs 24.6% more (3790 vs 3042) and required wider tires to drive like a normal car etc...
Big bummer with the V1 Volt is it also recommends Premium fuel while the Prius will run on regular.
So its like its a huge car but has the same interior space as the prius but one seat less.

[rmay635703]

The Volt fuel economy is all over the map
In many ways the 1st gen Volt is like an Insight

1. Only OEM tires return EPA
2. If it’s not 80F your fuel economy suffers
3. If your trip isn’t long you get low MPGs
4. Wrong oil drops mpgs

Many GM cars get terrible winter FE and I believe not enough effort is placed on cold running , emissions requirements paradoxically double fuel consumption during the first 5 minutes of engine use during very cold temperatures.

The Volt is ideal if you live in Florida or Cali and drive under 40 miles at a time for most trips, you would quite literally almost never use gas

[ksa8907]

Originally Posted by rmay635703

The Volt fuel economy is all over the map
In many ways the 1st gen Volt is like an Insight

1. Only OEM tires return EPA
2. If it’s not 80F your fuel economy suffers
3. If your trip isn’t long you get low MPGs
4. Wrong oil drops mpgs

Many GM cars get terrible winter FE and I believe not enough effort is placed on cold running , emissions requirements paradoxically double fuel consumption during the first 5 minutes of engine use during very cold temperatures.

The Volt is ideal if you live in Florida or Cali and drive under 40 miles at a time for most trips, you would quite literally almost never use gas

Looks like the only thing currently in my favor is long trips...

[cowmeat]

The Volt is ideal if you live in Florida or Cali and drive under 40 miles at a time for most trips, you would quite literally almost never use gas

Yup, that's me!

I changed the oil at the first of the year, and it's sitting at 99% oil life right now

[rmay635703]

Originally Posted by Ecky

I wonder why the Volt gets "such low" highway mpg. Did GM go with a relatively inefficient powerplant? Is it the tires? How efficient is the 1.4? I seem to recall reading that the related hybrids (Malibu?) had higher combined ratings on gasoline.

It’s not just the Volt, many newer cars including the Prius tend to get lower than expected “cool weather” economy.
Even my Cobalt is like that.

I own a volt and have found the best way to improve fuel economy is to optimize my trip for max EV miles

Small changes make big differences in EV range, my EV range virtually never drops below 50 miles,
This more than offsets the winter hit and makes the summer gain amazing.

At my peak during spring, summer and fall I consistently get 68-72 EV miles and 40-50 mpg off the gas pig alone, but I do hypermile a lot.

The summer gain makes up for the terrible winter driving.
But I still think it’s rather sad that my economy is cut in half or more during specific winter drives.

[ksa8907]

Converting today's electric usage to gasoline equivalent, I got 48.3 mpg over 118.8 miles.