DETROIT – General Motors Corp. unveils four new hybrid vehicles in as many hours during press preview week at the North American International Auto Show here, as it races to match rival Toyota Motor Corp. in consumer perception as an environmentally friendly auto maker.

In short, let the green wars begin.

GM began Monday’s show with the Cadillac Provoq concept car, the third application of its E-Flex system. The Provoq combines a lithium-ion battery that can be plugged in overnight for a recharge, with range-extending power from a hydrogen fuel-cell system.

GM admits the Provoq is a long-term vision, but the auto maker wants to bring its first iteration of E-Flex – the heavily publicized Chevrolet Volt plug-in hybrid electric vehicle – to market by 2010.

The Volt uses a small-displacement internal-combustion engine to back up its battery, which GM hopes will provide 40 miles (64 km) of emissions-free, all-electric travel. It also features plug-in capability.

The auto maker must develop a safe, reliable battery that will deliver the target range, says Bob Lutz, vice chairman-global product development, noting battery development is on schedule.

“So far, all the battery testing we’ve done has been bench-testing under various thermal conditions,” he says. “We’ve done rapid draw-downs on the battery, which stresses it a lot; we’ve cycled it up and down very quickly; (and we’ve) cut out the cooling system to see what happens if there’s a cooling-system failure.

“So far, we have not encountered any battery problems at all. They’re outperforming. We still have to do 10 years’ worth of cycling in a very short time. We (also) need battery packs that are closer to production.”

Additionally, GM must create an entirely new vehicle system, such as an electric-driven air conditioner. “It basically doesn’t exist today,” Lutz says. “We have to invent it together with our suppliers.

GM also has to reengineer components, such as audio systems, power-steering units and wiper systems, that use less electrical power. Reams of software to unite the Volt’s various vehicle systems also must be written.

Lutz says everything has to go just right to achieve the Volt’s production target, and so far it has. “So we’re confident. Normally you’d like more time, but we’re not going to take more time. We’re going to get it done.”

GM also unwrapped its ’09 Saturn Vue Green Line 2-mode hybrid cross/utility vehicle at the show, which unites a 300-volt battery pack with a 3.6L V-6 engine optimized by variable-valve timing and direct-fuel injection. A pair of active-cooled 73-hp (55-kW) electric motors integrated into the vehicle’s automatic transmission assist propulsion.

The system provides the greatest fuel economy in city driving, up to a 65% improvement compared with a traditionally gasoline-powered Vue that achieves 16 mpg (14.7 L/100 km) in the city. Production on the 2-mode model begins later this year.

GM has its 2-mode system in production already, first introduced on the Chevrolet Tahoe and GMC Yukon fullsize SUVs.

Sharing the stage with the Vue Greenline is a 2-mode PHEV version, which GM thinks will be the first commercially available plug-in when it comes to market in the 2010 timeframe.

The vehicle’s Li-ion battery delivers 10 miles (16 km) of emissions-free driving, and like the Volt, can be recharged from a household outlet overnight.

Saturn additionally shows a Flextreme concept car here, co-developed with GM’s German subsidiary. The Flextreme, which first bowed as an Opel brand at the Frankfurt auto show in September, represents the second application of the E-Flex system. It unites Li-ion battery power with a 1.3L turbodiesel engine.

“The Vue plug-in is about displacing petroleum, while the Flextreme would eliminate petroleum altogether,” says Larry Nitz, GM executive director-hybrid powertrains.

GM is not alone in flexing its green muscle.

Toyota, which with its popular Prius hybrid is perceived by consumers as the greenest of auto makers, now says it is speeding up its PHEV plans.

The Japanese auto maker originally targeted 2010 for the introduction of its plug-in hybrids, but Toyota President Katsuaki Watanabe says here he wants his engineers to meet an earlier deadline.

Watanabe insists Toyota, which currently offers three production HEVs, is not racing GM on the plug-in front, but “We don’t want to be the loser in that competition,” he tells a panel of reporters.

GM Chairman and CEO Rick Wagoner greets news of Watanabe’s new goal with a smile. “It juices up the competitive spirits, and I would think our guys will work even harder” after hearing Toyota’s goal, he says.

Unlike GM, Toyota expresses reservations over the stability of Li-ion batteries under high-volume manufacturing conditions. As a result, the company intends to stick with nickel-metal hydride batteries for the next-generation Prius.

Whatever the case, Lutz says GM and Toyota are neck-and-neck on plug-in development. “Technologically, we’re at about the same level.”

– with Christie Schweinsberg

jamend@wardsauto.com