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Mileage Climbing and Descending

BLE… I wasn’t talking about the same hill as your answer suggests. Please don’t take it out of context. How fast you would have to travel to maintain the same average would depend upon the time traveled within that ten mile total distance which if the same as 50, would be 90 miles per hour. Please read the "or " part of the statement which was conveniently disregarded in addition to the phrase “if at any time”.

Your example is not scientific but if it works for you, so be it. I can average nearly 30 mpg in my 4Runner too if I keep the speed below 55 with slight grades as I have done. But guess what, I could do better with no grades at all. Bottom line; it’s still a low 20s mpg highway at 65 to 80 mph and traveling around at less then 55 on slight grades does not prove a thing when wind resistance at higher speeds, which in part, determine our EPA figures, are disregarded. EPA uses level ground.

It is my contention that a car(yours) does better than highway or average mpg due to lower non stop and go speeds, and not because of slight grades. Just google terrain and it’s effects on mileage. I don’t feel I’m alone.

“As CR points out in their tests, when traveling, even with regenerative braking, the Volt with the engine running averages only 29 mpg both city and highway, much less then a Corolla.”

I suspect that when the Volt runs in engine mode, it’s because the battery has been used up and the engine is working to recharge the battery in addition to powering the car. This may account for the dismal fuel economy in engine mode.

Even though the Volt is officially a series hybrid, for efficiency it does help spin the wheels, I believe through the drive to the wheels but at a much lower % (10 to 15) then a true parallel. Without a charged battery from an outlet, as long as the battery is depleted and the car is driven the only way the car can move past the initial 35 miles give or take, is by the gas motor running with the mileage continuing to be as tested by CR. It never improves until it is charged from an outside source.

I don’t believe the gas motor will ever bring the battery up to charge enough to run it on electricity alone while driving as it’s chage capability is only allowing the electric motor to contribute the other 90%. Hence, past it’s depletion state for extended driving, it continues to be worse then a Corolla to perpetuity. If you have read anything different, I would be interested in hearing it. So not being a true series or parallel hybrid, you could call it a hybrid-hybrid. ;=) I guess. And, at $35 k I feel it’s a public relations rip off.

In it’s defense, I feel with out a traditional transmission and driven mostly by an electric motor, it has the potential to save the driver $$$$$ in other ways; mostly by very low maintenance and repair. Unless GM has built in some maintenance requirements to make themselves money, it could become one of the most reliable vehicles they have ever made, therefore necessitating the high initial cost.