At the end of September, Toyota and Mazda announced they would form a joint venture with parts maker Denso to design, test, and build components for a shared electric-car platform.

Earlier interviews with Mazda indicate that the small Japanese maker will create its first all-electric model for volume production by putting a unique body on top of those underpinnings, also used by Toyota.

On reflection, though, that rather begged the question: what about Subaru?

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The Japanese maker formerly referred to as "quirky" continues to boost its U.S. sales of all-wheel drive crossovers, hatchbacks, and sedans.

It's now had more than five solid years of month-over-month sales growth, in fact, doubling the capacity of its sole U.S. assembly plant in Indiana to meet the demand.

But despite its strong reputation for outdoorsy, environmental, socially concerned owners, Subaru has done very little in hybrids and almost nothing in electric cars.

Subaru Stella

Subaru Stella

It did produce several hundred examples of its low-volume Stella EV electric minicar, sold only in Japan, but the company killed that project in 2011.

Its homegrown Crosstrek Hybrid hatchback, sold from 2014 through 2016, was a mild hybrid that delivered only incremental fuel-economy gains at the expense of some drivetrain smoothness.

That car was quietly withdrawn from the lineup for 2017.

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Under the more aggressive California zero-emission vehicle quotas that take effect for the 2018 model year, Subaru will have to offer at least some number of vehicles that can operate in zero-emission mode some of the time.

Indeed, the company says its first plug-in hybrid vehicle is coming next year.

That will likely be a 2019 model, though whether it's the Crosstrek compact crossover hatchback, the Forester compact SUV, or the Outback mid-size crossover remains to be seen.

2014 Subaru XV Crosstrek Hybrid - Quick Drive, July 2014

2014 Subaru XV Crosstrek Hybrid - Quick Drive, July 2014

"We have a plug-in hybrid coming soon," confirmed Michael McHale, head of Subaru's U.S. communications group, adding after further questioning it would arrive "next year."

As for battery-electric models, however, McHale was circumspect.

His sole comment ran as follows: "In general, we are pursuing our own program, and will have a vehicle on the market in the 2020 timeframe."

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Indeed, Japanese media reports a year ago indicated that the company was developing its own, all-electric crossover utility for launch in 2021.

That would correspond nicely to McHale's suggestion of an introduction in 2020.

Meanwhile, its plug-in hybrid may be homegrown as well, or might use some elements of Toyota's hybrid system—though vehicle engineers suggest that the Toyota hybrid transmission would be very difficult to adapt to the flat-4 engines Subaru uses.

Subaru Viziv Future Concept, 2015 Tokyo Motor Show

Subaru Viziv Future Concept, 2015 Tokyo Motor Show

Subaru Viziv Future concept, 2015 Tokyo Motor Show

Subaru Viziv Future concept, 2015 Tokyo Motor Show

Subaru Viziv Future concept, 2015 Tokyo Motor Show

Subaru Viziv Future concept, 2015 Tokyo Motor Show

It's not surprising that fiercely independent Subaru is going its own way, since its experience with larger partner makers hasn't necessarily been positive.

GM bought a 20-percent share of Subaru in December 1999, but sold most of its holdings back to Subaru in 2005, except for 8.7 percent that went to Toyota.

The sole product from that marriage was the "Saabaru," a Subaru Impreza wagon dressed up to become the Saab 9-2X small car.

2005 Saab 9-2X

2005 Saab 9-2X

Another Saab project, the 9-6X that was a similarly camouflaged Tribeca three-row crossover, never reached production after the sale and instead provided the basis for a quick update of the Tribeca's controversial styling.

Toyota's first action as part owner was to build Camry sedans in the unused half of the Indiana plant, previously been shared with Isuzu, which had withdrawn from the U.S. market some years earlier.

The joint development project that produced the Subaru BRZ and Toyota 86 (nee Scion FR-S) two-seat sport coupe was reportedly fraught with disagreements among the two comapnies' engineers.


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