With the anticipated launch of the revised 2016 Chevrolet Volt range-extended electric car now less than a year away, expectations are that it will be a compact hatchback similar to the current model.

Whether it has four or five seats remains up in the air, though the addition of a fifth seat would clearly bring more buyers than the current, somewhat snug four-seat model.

DON'T MISS: 2016 Chevrolet Volt To Launch Next Year: What We Know So Far

2014 Chevrolet Volt

2014 Chevrolet Volt

The challenge in adding a fifth position lies in the Volt's current T-shaped battery pack, which fits inside a wide tunnel between the left and right sets of seats.

If the new 2016 Volt only has four seats, it would be at a capacity disadvantage against the Toyota Prius V, the Ford C-Max Hybrid and Energi models, and other high-mileage family five-seaters.

Forgotten concept

But there's a different alternative too: What if GM were to offer a second Volt model in a taller package that could seat five by putting the rear seat on top of the battery pack?

Such a vehicle was shown in China, as the Chevrolet Volt MPV5 Concept, back in 2010--and then it vanished from the auto-show circuit and hasn't been seen again.

That concept seated five and offered 30 cubic feet of cargo volume in a package larger than the existing Volt. While its 108.6-inch wheelbase was only 0.6 inches longer, the MPV5 Concept was 7 inches longer, almost 3 inches wider, and a full 7 inches taller than the five-door Volt now on sale.

2011 Chevrolet Volt MPV5 concept, Unveiled at 2010 Beijing Motor Show

2011 Chevrolet Volt MPV5 concept, Unveiled at 2010 Beijing Motor Show

That there may be more than one Volt is also supported by a Reuters article from two weeks ago.

That piece, however, suggested that the second model might be a less-expensive, lower-range Volt.

Significant spy shots?

Still, spy shots on Autoblog last July indicate that GM may well be developing a five-seat compact "tall hatchback" to compete with the Prius wagon and C-Max--but it may not use the Voltec powertrain. Instead, it could be a more conventional hybrid that doesn't plug in.

Those shots showed a development mule, using the company's existing Chevrolet Orlando compact tall people mover, testing a powertrain that included a high-voltage battery pack.

The test car doesn't, however, appear to have a charging port.

And using a smaller hybrid battery pack would eliminate the challenges of packaging a Volt-capacity battery while maintaining adequate cargo volume--an issue for which the Ford C-Max Energi plug-in hybrid has been slammed.

Built on Cruze underpinnings, the Orlando is sold in Canada and on other continents--but it was never brought to the U.S.

2011 Chevrolet Orlando

2011 Chevrolet Orlando

More compact models to come

GM's mass-market brand is developing multiple vehicles on an updated platform that was introduced at last week's Beijing Auto Show, in the form of an all-new Chevrolet Cruze compact sedan.

That car will arrive in the U.S. as a 2016 model, but its underpinnings will undoubtedly spawn several other vehicles--including the next generation of Orlando.

Compact tall hatchbacks like the Chevy Orlando and Ford C-Max are a very popular global segment, even if their U.S. sales aren't particularly stellar at the moment.

The puzzlement lies in a basic technology question: What hybrid system would GM use?

Full hybrid--from where?

To get truly notable gas-mileage ratings--40 mpg or more combined--it would have to be a full hybrid, not the company's eAssist mild hybrid.

And GM appears to have given up on downsizing its large, sophisticated, and brutally expensive Two-Mode Hybrid system designed for full-size SUVs and pickup trucks.

So is the company developing an all-new hybrid system, using elements of the Voltec powertrain and a smaller battery pack that doesn't plug in?

Given that it has a technology partnership with Honda on hydrogen fuel-cell vehicles--which contains language saying it could be extended to other technologies--might it be using Honda's new two-motor hybrid system, as seen in the 2014 Honda Accord Hybrid?

General Motors, predictably, declined to comment on any of the speculation.


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