The upcoming Audi e-tron could be the German luxury establishment's most direct answer yet to Tesla Motors.

It's a mid-size SUV with an all-electric powertrain--a description that seems to match that of the Tesla Model X.

And we may get an opportunity before the end of the year to judge just how the upcoming Audi compares to Tesla's first utility vehicle.

DON'T MISS: Audi Q6 e-Tron All-Electric 'Coupe SUV' Confirmed For 2018

The all-electric SUV with coupe-like styling isn't expected to appear in showrooms until 2018, but we'll apparently get a preview of it much earlier.

A concept version of the e-tron has been tipped for a debut at the 2015 Frankfurt Motor Show in September.

Audi will offer the first glimpse of its "Tesla Model X fighter" there, according to unnamed sources cited by Automotive News Europe (subscription required).

2016 Audi Q7 e-tron quattro

2016 Audi Q7 e-tron quattro

The e-tron may be one of a number of variants of an upcoming Q6 model--including versions with conventional gasoline and diesel powertrains.

Plug-in hybrid and hydrogen fuel-cell versions are also possible, the sources said.

They also claim the Q6 will be based on the same Volkswagen Group MLB platform as the recently-introduced second-generation Audi Q7.

ALSO SEE: Audi, BMW, Mercedes, Porsche Electric Cars To Target Tesla Model S (Plug-In Hybrids Too) (Dec 2014)

Indeed, the Q6 and Q7 could turn out to be very similar.

Audi may plan to pitch the Q6 as a "coupe" version of the Q7, with body styling being the primary difference between the two models.

The company released a teaser sketch last year of a vehicle with the tall body of an SUV, but a much lower roofline.

Tesla Model X at 2013 Detroit Auto Show

Tesla Model X at 2013 Detroit Auto Show

That would give Audi a rival to the existing BMW X6 and Mercedes-Benz GLE Coupe, as well as the Model X.

Audi technical chief Ulrich Hackenberg previously said the company is aiming for a 310-mile range with its first electric SUV.

That's likely in terms of the European testing cycle, though. The rated range for the Q6 e-tron on the U.S. EPA cycle might come closer to 250 miles.

MORE: How Audi, BMW & Mercedes Plan To Compete With Tesla--And Why (Oct 2014)

If Audi offers the Q6 with multiple powertrain options, the electric e-tron version could get some styling elements to distinguish it from internal-combustion models.

Audi previously confirmed the e-tron model would arrive in 2018, although other versions of the Q6 may launch before that.

The introduction of a Q6 concept in Frankfurt would certainly leave time for at least a couple of Q6 variants to launch before 2018.

And when it does launch, the Q6 e-tron will likely represent much smaller volumes than other Q6 variants, although perhaps not as small as Audi's other electric car--the R8 e-tron--which will only be built to order.

[EDITOR'S NOTE: The Audi e-Tron Quattro Concept, first unveiled at the 2015 Frankfurt Motor Show, was long expected to carry the Q6 designation when it launched as a production vehicle in 2018 or later. In October 2016, however, Audi said the production version would be called simply Audi e-tron. We have updated this article accordingly.]


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