Yesterday's multi-hour presentation of the five-year plan for the combined Fiat Chrysler Automobiles was called "Chryslerpalooza" by local Detroit reporters who sat through it.

The first green news was that Chrysler will build small numbers of plug-in hybrid minivans and large SUVs to meet emission regulations.

But in an afternoon technology briefing, Chrysler said it will incorporate mild hybrids into many future powertrains.

ALSO SEE: Jeep Five-Year Plan: An SUV For Every Niche

The company sees its proportion of diesel engines staying steady at about 6 percent of its total sales (which will rise), while the number of vehicles it builds with V-8 engines will fall from 21 percent last year to 12 percent by 2018.

2013 Chrysler 300 SRT8 Core Live Shots

2013 Chrysler 300 SRT8 Core Live Shots

It plans to reduce its total number of vehicle "architectures" from the current 18 to 15 by 2018. And, it said, 95 percent of its sales will stem from just nine of them.

In total, the combined company expects to save roughly a cumulative $2.1 billion in costs over the next five years from this standardization and the elimination of duplicate and low-volume powertrains and parts.

As for advanced powertrains, the company says hydrogen fuel cells are "not commercially viable for mainstream automobiles"--even though Hyundai, Toyota, and Honda will launch small numbers of mass-produced hydrogen vehicles over the next two years.

And, it said, plug-in electric cars have been "overblown by the media"--going on to elaborate:

Electrification has been over-blown by the media. With the exception of a relatively small group of early adopters, the market continues to be primarily driven by regulatory requirements.

While Chrysler plans to launch two plug-in hybrids of its own, those are merely to "comply with zero-emission vehicle requirements." In other words, they will be built only in compliance-car volumes.

MORE: Chrysler's Future: A New Minivan, A New Compact Sedan, And Crossovers

As for the mild hybrids, they won't come until 2017 or later.

First comes a new family of small gasoline engines, likely replacing the 1.8-liter to 2.4-liter engines it inherited from a joint Chrysler-Hyundai-Mitsubishi partnership, now renamed "Tigershark."

The mild hybrid system--Chrysler calls it BSG, for Belt-Starter-Generator--will allow smaller engines to be assisted by electricity stored in a small high-voltage battery pack.

Such systems are generally not capable of moving the car on battery power alone, unlike full hybrids.

Buick Lacrosse Hybrid eAssist System

Buick Lacrosse Hybrid eAssist System

General Motors, which has leaned on its eAssist mild-hybrid system in various Buick and Chevrolet models, has not seen the sales growth it had expected for that system.

Instead, it is expected to double down on its Voltec range-extended electric vehicle technology, and launch a full hybrid system within the next several years. Ford will rely on its growing sales of hybrid models.

Like every other carmaker, Chrysler's technology advances over the next five years will be in service of meeting the increasingly stringent corporate average fuel economy (CAFE) rules in effect from 2012 through 2025, which will boost CAFE to a 54.5-mpg average--which translates to about 42 mpg on the window sticker.

At least a few plug-in vehicles are required to meet those goals, but every vehicle must get significantly more fuel-efficient--and Chrysler's deficit of high-volume passenger cars and strong reliance on crossovers, SUVs, and pickup trucks puts it at a disadvantage to its competitors.

Finally, Chrysler will continue to purchase carbon-dioxide credits from other carmakers, to meet its requirements under a little-known EPA credit-trading program.

"This buys us time," said Chrysler's Bob Lee.

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