A few years ago the concept of a green sports car would have been completely alien, but fast-forward a few years and the market has changed significantly.

Tesla, for a time, produced its electric Roadster. Ferrari, Porsche and McLaren have all released hybrid hypercars. And with its next-generation R8 sports car, Audi could offer both diesel and electric variants.

The 2016 Audi R8 is set to make its debut next year, reports Automobile, replacing the current model that has endured since its launch in 2007.

Initial plans suggested the new model would be smaller, lighter and powered by smaller engines than its predecessor--helping distance the model from Lamborghini's lower-end models, the Italian marque also owned by the Volkswagen Group.

However, it's now likely the new car will offer V-8 and V-10 power units as before.

Neither of those will appeal to greener-minded buyers of course, but two other variants might.

Volkswagen Group boss Ferdinand Piëch has long held a diesel R8 as a pet project--among others like the Bugatti Veyron and "eco supercar" Volkswagen XL1.

With the new R8 the diesel model could finally hit the streets, using either a modified version of Audi's 4.0-liter turbodiesel V-8 or a new 5.0-liter V-10 TDI, which the group is developing for future Bentley models.

We'd not expect either engine to provide Jetta TDI-rivaling economy figures, but for the car's intended market the torque, relaxed power delivery and economy of a large turbodiesel could make the car a formidable long-distance tourer.

The second "green" R8 is one we've known about for some time: The R8 e-tron.

The electric version is still part of the program, and said to offer double the range of the R8 e-tron prototype we drove in Berlin last year.

Dropped and restarted several times in the past, Audi now believes the R8 e-tron can offer the performance and range its buyers expect, and should fit right into Audi's future range--which could offer a plug-in version of every significant model.


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