Volkswagen Tiguan GTE PHEV concept sports a solar panel roof
Volkswagen has revealed the Tiguan GTE plug-in hybrid concept at the 2015 Frankfurt Motor Show. Power comes from a 154-horsepower turbocharged four-cylinder engine combined with an electric motor for a total output of 214 hp, sent through a six-speed dual-clutch transmission. In all-electric mode, the Tiguan GTE can hit a top speed of 80 mph and cover 31 miles, thanks,&nbsp;in part, to a solar module that is integrated into the roof. VW says that over the course of a year, the solar panel will add roughly 620 miles of all-electric driving. It is unclear whether Volkswagen plans to make a production version of the Tiguan GTE. 
Nathan Bomey

USA TODAY

Volkswagen revealed a redesigned Tiguan crossover at the Frankfurt Motor Show, part of its bid to solidify its new-found status as the world's largest automaker and give a jolt to its portfolio in the U.S.

It is expected to hit European showrooms in April and arrive in showrooms in the U.S. and China late next year.

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Engineers said they've improved the crossover's fuel economy by 24% while boosting cargo capacity by 11%. The aerodynamically improved vehicle is 1.3 inches lower, 1.2 inches wider and 2.4 inches longer than its predecessor, tracking a general industry design trend. And it's equipped with safety features such as a system that raises the hood in an accident if a person crashes into it, reducing the chances that the person's body will endure a hard impact from the engine.

The German automaker also revealed a plug-in hybrid concept version of the crossover, dubbed the Tiguan GTE, with a solar roof.

The conventionally-powered Tiguan is part of what Volkswagen described as "an SUV product offensive" — with an emphasis on the U.S., China and Europe.

The company recently claimed the title of world's largest automaker for the first six months of the year, edging Toyota.

But to maintain that position, it must bolster its lineup of crossovers — best described as a blend of cars and SUVs — a segment in which the company has had shortcomings in the U.S. The Tiguan hadn't gotten a total overhaul since 2007.

Europe is getting a Tiguan with a shorter wheelbase than the vehicle that will be delivered to consumers in the U.S. and China, where consumers prefer longer vehicles. It's the first vehicle to be based on an all-new internally developed global chassis.

The company showed off several versions of the vehicle in Frankfurt, including the sporty R-Line, Trendline, Comfortline and Highline, most available with off-road packages. Designers gave the Tiguan dual LED headlights.

But the Volkswagen reveal that draws the most attention in Frankfurt could be the Tiguan GTE plug-in hybrid concept with solar roof.

The plug-in uses a 13-kilowatt-hour lithium-ion battery that enables 31 miles of electric driving before a gasoline engine kicks in. The solar roof could generate as much as 621 miles of electric driving range over the course of a year in ideal conditions, the company said.

It's unclear whether Volkswagen plans to make a production version of the Tiguan GTE. The introduction comes as luxury automaker Tesla Motors is expected to deliver the first versions of its Model X electric crossover this month.

Follow USA TODAY reporter Nathan Bomey on Twitter @NathanBomey.