Audi just wrapped up a four-year electric-car test program in its home market of Germany—and the company says it has learned a lot.

Conducted together with the German government, it put plug-in electric cars in the hands of ordinary drivers, who covered a combined 1.4 million kilometers (870,000 miles).

As with other such carmaker trial programs, the goal was to gather real-world data on how consumers used electric cars and how they reacted to them.

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Those reactions were mostly positive, Audi says, with some concerns about lack of charging infrastructure mixed in.

The initial phase of the program included deployment of 80 Audi A1 e-tron extended-range electric prototypes.

Based on the A1 subcompact sold only in Europe, the e-tron uses an 85-kilowatt (114-horsepower) electric motor and lithium-ion battery pack, with a Wankel rotary engine as a range extender.

Audi A1 e-tron first drive, Berlin

Audi A1 e-tron first drive, Berlin

Audi subsequently added 40 production A3 Sportback e-tron plug-in hybrids to the trial, versions of the model that went on sale in the U.S. last December.

On sale in Europe since late 2014, the A3 e-tron has a 1.4-liter turbocharged four-cylinder gasoline engine and six-speed dual-clutch transmission, working with an electric motor and an 8.8-kilowatt-hour lithium-ion battery pack.

No matter what car they drove, participants covered the majority of mileage on electric power, according to Audi.

ALSO SEE: Audi A1 e-tron: First Drive Of Range-Extended Electric Car Prototype (Jun 2013)

A1 drivers completed 87 percent of their travels on electric power, while A3 drivers used electric-only running 70 percent of the time, the carmaker says.

One particularly efficient driver only filled up the gas tank once in five months, despite covering 7,700 km (4,780 mi).

That's in part because the majority of all drivers' trips were relatively short.

2016 Audi A3 e-tron - First Drive

2016 Audi A3 e-tron - First Drive

Participants averaged less than 50 km (31 mi) per day, and around half of trips were under 10 km (6.2 mi), Audi says.

Nonetheless, Audi says drivers' level of comfort with the cars was still largely dependent on the availability of public charging stations.

MORE: Audi e-Tron Quattro Concept: 2018 Q6 Electric Car Previewed At Frankfurt Motor Show (Sep 2015)

Audi itself is expected to invest in DC fast-charging infrastructure to support its upcoming Q6 e-tron all-electric SUV.

This will be a production version of the e-tron Quattro concept unveiled at the 2015 Frankfurt Motor Show, and will debut in 2018.

Perhaps some of the insight into consumer habits Audi gleaned from the German test program will prove useful in the launch of that model.


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