The first production versions of the Chevrolet Volt are rolling down the line, with official sales set to begin in December.
The Chevrolet Volt gets the equivalent of 93 miles per gallon when run in electric-vehicle mode, the U.S. Environmental Protection Agency has declared, and 37 miles gallon when it switches to its onboard gasoline engine.
Coming up with a rating for the Volt was a significant challenge for the EPA because of the multiple modes of operation available for the 2011 Chevy hybrid, which General Motors prefers to call an “extended-range electric vehicle,” or E-REV. Unlike a conventional hybrid, which typically can get no more than a short run on battery power alone, Volt is capable of running for up to 50 miles in electric vehicle mode. But, unlike pure battery-electric vehicles, it can switch to gasoline power for longer journeys.
In this mixed-mode operation, the EPA has decided, the 2011 Chevrolet Volt will carry a 60 mpg rating on the Munroney sticker, mounted on the vehicle’s window for motorists to use when comparison shopping.
The agency also determined that with a full charge and a full tank of gas Volt can travel 379 miles before needing to be either refilled or plugged back in again.
The news came days after the EPA gave the Nissan Leaf, a pure BEV, a 99 mpge rating, the “e” standing for equivalent, reflecting the fact that government analysts had to decide how to make a meaningful comparison between the energy usage of a battery-powered vehicle and a conventional gasoline or diesel automobile. (Click Here for more on the ratings for the 2011 Nissan Leaf.)
The EPA meanwhile determined that despite Nissan’s claim of an average 100 miles range per charge for the 2011 Leaf that its Munroney sticker show a 73-mile range. That reflects the fact that battery-powered vehicles are subject to extensive variations in performance due to factors such as driver behavior, road conditions and even the weather. On a cold winter morning, with the heater blasting and the vehicle creeping along in heavy traffic, a battery car like Leaf could see its range nearly cut in half.
While Volt’s 93 mpge rating is a significant showing – and only 6 mpge lower than Leaf – the 37 mpg rating for its gasoline mode is not nearly as impressive considering the growing number of models in the compact class that are actually nudging up to and even exceeding the 40 mpg mark, often without the use of hybrid assistance. That includes the upcoming replacement for the Hyundai Elantra (Click Here for more), which is expected to get over 40 mpg on the EPA Highway cycle.
Even Chevrolet’s conventional compact sedan, the 2011 Cruze, will pop over the 40 mpg mark if ordered with the Eco option.
But GM claims Volt’s gasoline engine is only meant to be a backup that eliminates the so-called “range anxiety” normally associated with pure battery-electrics. The maker points to government data showing that roughly two-thirds of all Americans drive less than 40 miles per day. They would normally operate Volt on battery power alone, the maker contends.
Indeed, assuming large numbers of its customers will go for an extended period without Volt’s inline-four engine firing up, GM engineers had to come up with a way to ensure the gasoline in its tank would remain fresh when eventually used.
Getting its Munroney sticker approved by the government was a critical step in the roll-out of the 2011 Chevrolet Volt, the first car set to reach customers in the coming weeks. Under U.S. law, a vehicle cannot be sold without the window sticker.