This article or section contains information about a . It is likely to contain information of a speculative nature, though such must be attributed to relevant sources. Concept cars, by definition, rarely become production models, and any given specifications may change significantly as development progresses.

Chevrolet Volt Concept
Manufacturer	General Motors
Production	concept - late 2010
Class	Compact car
Body style(s)	4–5 passenger, 4-door liftback
Layout	FF layout
Platform	Delta/E-Flex
Engine(s)	1L 71 hp 3-cylinder, 120 kW electric
Transmission(s)	direct
Length	170 in / 4318 mm [1]
Width	70.5 in / 1791 mm
Height	52.6 in / 1336 mm
Fuel capacity	45 L / 12 US gal + 16 kWh

The Chevrolet Volt is a plug-in hybrid concept car created by General Motors. However, the company has avoided the use of the term "hybrid," preferring to call it an electric vehicle with a "range extender" due to its design.^[2] The vehicle is designed to run purely on electricity from on-board batteries for up to 40 miles (64 km)—which is a large enough distance to cover the daily commutes of most Americans, which is around 25 miles (40 km). With use of a small internal combustion engine hooked to a generator to resupply the batteries, the vehicle's range is potentially increased to 640 miles (1030 km) on the highway. General Motors Corp. may build as many as 60,000 of its Volt electric cars for their inaugural year on the market, four times the sales of Toyota Motor Corp.'s hybrid Prius. ^[3]

The Volt concept vehicle was officially unveiled at the North American International Auto Show (NAIAS) on January 72007 in Detroit, Michigan.[1] An updated version was unveiled at the Shanghai Auto Show in April 2007 in Shanghai, China. At the time of unveiling, the Volt project had been in existence for less than a year. It was started in 2006 after Robert Lutz, Vice Chairman of Product Development and Chairman of GM North America, learned of plans for the Tesla Roadster, a high-performance electric sportscar.^[4] While the Roadster has a target price at or near US$100,000, the Volt is targeted to cost around $20K to 30K^[5].

E-Flex drivetrain

The concept vehicle appeared in the Detroit Auto Show^[6] introduces the E-Flex^[7] drive system, which is an attempt to standardize many components of possible future electrically-propelled vehicles, and to allow multiple interchangeable electricity-generating systems. The initial design as envisioned in the Volt combines an electric motor and 16 kWh (57.6 MJoules) lithium-ion battery plug-in system^[8] with a small engine (1 litre) powered by gasoline linked to a 53-kW generator. The vehicle is propelled by electrical motors with a peak output of 120 kW (160 horsepower). Ordinarily, the vehicle would be charged while at home overnight (plug-in hybrid). A full charge reportedly takes 6.5 hours from a standard North American 120-volt, 20-Amp household outlet. Two charging ports exist on the vehicle, one on each side, so the most convenient one can be used.^[9]

Since the electrical drivetrain doesn't care how its generator is being driven, several options could be available for an engine. The primary configuration specified in promotional literature uses a turbocharged 1.0-liter engine with three cylinders. It would be a flex-fuel engine capable of running gasoline or E85 (85% ethanol, 15% gasoline). Fuel would be supplied from a "saddle" tank 45 liters (12 gallons) in size.

The second option is the Volt Fuel Cell Vehicle, appeared in the 2007 Shanghai Auto Show.^[6]

Other options have also been mentioned, such as a pure ethanol (E100) engine, a diesel engine capable of running biodiesel fuel, or even a hydrogen fuel cell, once that technology becomes practical (the Ford Airstream concept, which debuted at the same show, uses a fuel cell plug-in hybrid design).

This general layout is considered a plug-in series hybrid design since mechanical power initially drives the generator, which in turn charges the battery pack. Power is then drained from the batteries to run the electrical motors which move the vehicle. The internal combustion engine does not have any mechanical linkage to the wheels (unlike current vehicles such as the Toyota Prius), and it can run at a constant rpm for optimal efficiency.

GM plans to keep the lithium-ion battery in a state-of-charge (SOC) range of between 30% and 80%, with the on-board generator kicking in at the 30% level.^[10]

Related and similar vehicles

The concept vehicle has four doors with a rear liftgate, and is capable of carrying four to five passengers. This is an improvement over General Motors EV1 of the 1990s, which only seated two. The top speed has also been increased on the Volt, from 80 mph (nearly 130 km/h) to 120 mph (over 190 km/h). The battery pack size has also been reduced between the two, from about 300 liters in volume on the EV1, to just 100 on the Volt.

The purely electric range of the Volt will be considerably smaller than that of the EV1, but the overall range will be much higher. However, there was a 1998 prototype version EV1 in series hybrid configuration, that also had four seats and the same 40 miles of all-electric range as the Volt, and featured combined range of 390 miles. In contrast to current Volt, this car was actually a running prototype.

The Opel Flextreme concept vehicle is based on the same platform and technology, but designed for a European market; including a diesel engine, and a hatchback body.

Production plans

Although a production date has not been announced, several sources have speculated that General Motors hopes to have the Volt on the market in 2010. ^[11] To help spur battery research, GM selected two companies to provide advanced lithium-ion batteries: Compact Power and Continental Automotive Systems. ^[12] However, on August 9th, 2007 GM selected A123 to provide batteries. ^[13]

Clearly, battery technology will have a large impact in determining the success of the car. Critics of GM have suggested that the Volt concept car may be a political ploy to help the company defeat proposed fuel economy increases mandated by the Corporate Average Fuel Economy (CAFE) regulations. ^[14]

Bloomberg.com reported on August 22, 2007 that the initial production run for the Volt may be as many as 60,000 vehicles, or four times the sales volume of the Toyota Prius in its first year.^[15]

With the outcome of the 2007 UAW-GM contract talks, assembly of the Volt was assigned to Detroit/Hamtramck Assembly.^[16]

See also

• Denis Gray, GM´s battery testing lab director.
• General Motors EV1
• General Motors XP-883
• Genset trailer
• Opel Flextreme
• Tesla Roadster

References

External links

• Automotive Forum Dedicated To The Chevrolet Volt.
• Official Chevrolet page about the Volt
• AutoblogGreen: It's Here: GM's Plug-in Hybrid Is the Chevy Volt
• Leftlane News: GM Reveals Chevrolet Volt Concept
• Cost of Operating the Volt