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my charger has just packed up, and whilst I wait of another in the post, I'm stuck with ICE for my local town stop/start driving. yesterday I did 22 miles in total and managed 27.5mpg (US) and today drove only 7.7 miles at 18.5mpg (US) it's 6c here, rainy and windy.... but I guess there are some pretty serious losses when driving in town on a probably cold ICE engine, it's on and off like crazy, and no amount of seriously careful driving can get that efficiency up

hope the post comes soon ! this thing does not rival a typical hybrid for use when on its extended range.... but what a nice car, really chuffed overall :)
 

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Never drove around town on ICE but I have done highway driving, half hilly, half flat, half curvy, half straight. The ice shuts off, running on battery buffer when going down hill or slowing down coasting up to a stop light and turns on when going up hill, on the flat or needing to fill the battery buffer (shown as a max of one bar, Gen1). Get pretty good mileage I feel but never did a calculation as I rarely use gas except once a month car meeting and four times a year to airport. The ICE was never off long enough to "cool down".
 

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my charger has just packed up, and whilst I wait of another in the post, I'm stuck with ICE for my local town stop/start driving. yesterday I did 22 miles in total and managed 27.5mpg (US) and today drove only 7.7 miles at 18.5mpg (US) it's 6c here, rainy and windy.... but I guess there are some pretty serious losses when driving in town on a probably cold ICE engine, it's on and off like crazy, and no amount of seriously careful driving can get that efficiency up

hope the post comes soon ! this thing does not rival a typical hybrid for use when on its extended range.... but what a nice car, really chuffed overall :)
Try running in Mountain mode for a while to build up some charge. Then use that charge until your new charger comes in the mail.
 

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Believe it or not you still did better than the average ICE vehicle, but yea, those numbers sound low for a hybrid. I usually only burn gas on the freeway and I get 36 to 41 depending on speed, etc. You must have a bad combination of weather and driving environment. Also be sure to use premium fuel since regular will drop your MPG and gas range.
 

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I got 1.3 km on .25 liter - REALLY POOR. As you don't say where you are or what model you own. Mountain mode until you get your EVSE. I'm guessing England as POST is not very common in N.A.
 

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Cold, short trips will do that. Even our Prius (47 - 52 mpg on longer trips) will dip down into the upper 30's with 3 miles here, 5 miles there.
 

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my charger has just packed up, and whilst I wait of another in the post, I'm stuck with ICE for my local town stop/start driving.
You aren’t "stuck with ICE" just because you can’t charge from the wall, especially if you’re driving a Gen 1 Volt. You can use Mountain Mode to recharge the Gen 1 battery to the ~4 bar level, then use MM-recharged battery power for your stop and go driving. This might be a more efficient use of the gas than remaining in Extended Range Mode and using the engine.

Switching to Mountain Mode, in effect, raises the Gen 1's "switch to ICE" state of charge from 0 bars to the ~4 bar level (i.e., it creates a larger buffer of "borrowable" power for use in high power demand driving conditions).

If your battery soc is below that level or even fully depleted, MM’s "recharging feature" will recharge the battery to the ~4 bar level (Wikipedia says that’s at the 45% soc level for 2011/2012 Volts). The Self Charging Chevy Volt video shows a 2012 Volt’s fully depleted battery being recharged to the MM-maintained level (~14 battery miles) in 15 minutes using 0.36 gallons of gas. Later models with larger batteries may use a bit more.

One can switch to MM and recharge the battery while driving, but if you try it while parked (as is done in the video), your energy usage display will show you how much gas is consumed in the process without also including the gas consumed to move the car down the road. You also learn it takes only ~15 minutes (that’s why the manual says to switch to MM ~20 minutes before reaching any mountain roads).

Math suggests that with my local prices, it costs about $0.50 US more to charge my 2012 Volt’s battery to the ~ 4 bar level using gas (MM) than using electricity from the wall, so it is a bit more expensive method of recharging, but not too much.

As mentioned, when driving in Extended Range Mode, the engine is turned off and on as needed to minimize fuel use while meeting the power needs of the motor. When MM is recharging the battery, the engine is running full out until the battery is charged to the MM-maintained level. This provides better fuel economy during the recharging of the battery. The end result is that, if MM could fully recharge the Gen 1 battery, it would use just under 1 gallon to do so.

One could then drive 35-38 battery powered miles (depending on model year) in a Gen 1 using a battery that was fully recharged via MM by using ~1 gallon of gas in the generator, or about the same distance you could drive in normal Extended Range Mode using 1 gallon of gas in a car rated at 37 mpg.

Of course, driving conditions are variable, and the conditions actually experienced will determine if "MM-battery powered miles" or just normal Extended Range Mode driving produces the better trip gas mileage. You have noted that your "cold engine, stop and go driving" gets lousy gas mileage. Running on MM-recharged battery power may be a better choice under such conditions.

Be aware, however, that once your battery has used up all the grid power from the previous from the wall charging, the MM-recharged battery distances are supposed to be recorded as Gas miles/km (because gas was used to charge the battery). Once you turn the car off, then restart it, the computer notes the state of charge is above the "switch to gas" soc, and starts crediting the "MM-recharged battery power" distances to Electric distances (without increasing the kWh Used because it’s not grid electricity). That plays havoc with Electric/Gas statistics.

The Volt concept is to minimize the use of gas, so this MM "fast self-charging" feature won’t allow you to fully recharge the battery. It could be that frequent "fast charging" the Volt battery would significantly shorten battery life (I’m not sure if this topic has ever been discussed).
 

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Mountain mode uses more gas than just driving it normally.

https://youtu.be/giV5t5-_gyo?t=405
My evaluation indicates that if the Mountain Mode "recharging" feature could fully recharge the battery instead of stopping at the ~4 bar level, it would use about 1 gallon of gas to do that. Gen 1 window sticker ratings suggest the full charge ev range is about the same as the range for using one gallon of gas.

Clearly, the actual battery driving range for a full charge or gas driving range for one gallon of gas depends on the driving conditions.

This thread has the OP making several short trips in stop and go traffic in cold weather. I think the distance he could drive on a MM-recharged battery would be greater than the distance using the same amount of gas in a cold engine.

The conditions are different in the video, where the 2013 Volt is cruising long distances at highway speeds. Those conditions would provide good gas mileage, and burning gas in Extended Range Mode might indeed provide better fuel economy.

The video, however, has its faults. The narrator started the trip with a full charge and an estimated 75 km ev range, and it is not clear if the documented first leg 477 km trip included some or all of that ev use (i.e., 75 ev km plus 402 gas km?). The narrator also admitted that the 424 gas km return trip may have included additional use of air conditioning, etc. The fuel consumption on each leg of the trip could have been better documented.
 
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