It may be the most star-crossed program in recent automotive history, and now it's apparently dead.

According to Reuters, General Motors has canceled work on the planned plug-in hybrid version of its Cadillac SRX crossover sport utility.

The canceled SRX plug-in would have been the second GM car, after the 2011 Chevrolet Volt extended-range electric car, to plug into grid electricity to recharge a lithium-ion battery pack that provides all-electric running.

Too costly, too late?

Unnamed sources gave several reasons, among them that the SRX plug-in would have lost money, that the changes it required would have come late in the SRX's life cycle, and that consumers may have become more interested in fully electric cars with range-extending engines.

The current SRX crossover was unveiled in January 2009 and went on sale as a 2010 model.

Saturn Vue Two-Mode Hybrid

Saturn Vue Two-Mode Hybrid

The SRX plug-in hybrid, however, would not have used an electric motor as the sole source of power to drive its wheels, as the 2011 Chevy Volt does (with a very minor exception).

Instead, like Toyota's Hybrid Synergy Drive system, it combines torque from the gasoline engine and a pair of motor-generators. It can use one, the other, or both.

The all-electric range of the SRX plug-in would have been about 10 miles. And the engine would still have come on whenever the vehicle felt it was needed--just as it does in the 2012 Toyota Prius Plug-In Hybrid that Toyota expects to be the cheapest plug-in in the U.S. when it launches by June 2012..

From Vue to Vuick to SRX

The plug-in hybrid is an adaptation of GM's Two-Mode Hybrid system now sold in small numbers on versions of the Chrevrolet Tahoe, GMC Yukon, and Cadillac Escalade full-size sport utility vehicles, as well as the Chevy Silverado and GMC Sierra pickup trucks.

Originally, the plug-in Two-Mode system was intended to launch in a version of the Saturn Vue crossover that was to go on sale in 2010. GM's bankruptcy and the subsequent termination of the Saturn brand killed that program.

Then the Vue was briefly proposed to be re-badged as a Buick in a widely derided program nicknamed the "Vu-ick," mercifully killed after several weeks. (The Vue is now back on the U.S. market, but only for fleet purchases, as the 2012 Chevrolet Captiva.)

2009 teaser shot of Buick crossover plug-in hybrid, a rebadged Saturn Vue quickly dubbed the 'Vuick'

2009 teaser shot of Buick crossover plug-in hybrid, a rebadged Saturn Vue quickly dubbed the 'Vuick'

In January 2010, former GM product czar Bob Lutz told reporters the company's first plug-in hybrid would be a small crossover. That meant the GMC Terrain, Cadillac SRX, or even the Chevrolet Equinox.

Late last year, rumors pointed instead to the Cadillac SRX, based on--among other things--comments by CEO Dan Akerson.

RIP? Maybe not

Now, the SRX Plug-In Hybrid is apparently dead.

But is that the end of Cadillac's plug-in hybrid hopes?

Perhaps not.

Given GM's policy of greater distinction among its brands, Chevrolet will have the Volt electric car. Buick will launch the eAssist mild-hybrid system in its 2012 Buick Lacrosse, though the word "hybrid" will appear nowhere in the marketing or promotion.

That leaves Cadillac as the company's home for hybrids, which makes sense, since its larger, high-performance, more luxurious vehicles will require additional effort to meet upcoming U.S. gas-mileage standards.

Remember the XTS

Cadillac XTS Platinum Concept

Cadillac XTS Platinum Concept

What's not at all clear, however, is whether the Plug-In Two-Mode Hybrid will appear in the forthcoming 2013 Cadillac XTS full-size sedan, which replaces both the Cadillac DTS and STS sedans. DTS production ended last week, with STS manufacturing having already stopped early in the month.

The XTS is the production version of a rapturously received design study from the 2010 Detroit Auto Show, known as the Cadillac XTS Platinum Concept. That model included a plug-in hybrid system, and the 2012 XTS will be a brand-new vehicle when manufacturing starts next year.

A version of the XTS with 10 or more miles of low-speed electric running would match up neatly against the upcoming new Mercedes-Benz S-Class Plug-In Hybrid, which the company will launch next year.

Any bets on, say, a 2014 Cadillac XTS Plug-In Hybrid, anyone?


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