Despite the uncertain future of once facing GM’s European brands, the Vauxhall/Opel division will unveil a dramatic concept car at this year’s Geneva Auto Show that. The Flextreme GT/E illustrates how extended-range electric vehicle (E-REV) technology can be plugged into large or mid-sized vehicles, as well as compact cars, like its upcoming Ampera model.
Sleek and aerodynamic, the Flextreme GT/E achieves a projected drag co-efficient of just 0.22, allowing it to reach an estimated top speed of 125mph-plus while conserving energy and extending the driving range.
Stand-out visual features include a low, wide stance, wing-shaped lights, a distinctive nose and grille, ‘floating’ C-pillars and muscular, sculptured bodywork. The clean frontal styling features a low hood line and an extended nose section, which is clasped by wing-shaped, signature LED headlamps, which are in turn carved into the front fenders and across the hood line.
The new trapezoidal grille is slim but bold, with the prominent wing-shaped chrome bar carrying a large Vauxhall emblem, which doubles as a socket for charging the Flextreme GT/E’s battery pack.
The upper section of the grille ingests cooling air, the lower portion being covered by a translucent panel. The absence of additional air intakes allows a low frontal area for aerodynamic efficiency and enables the Flextreme GT/E to meet future pedestrian protection requirements. The sculpted hood, with a Vauxhall-signature central crease, features narrow longitudinal vents on either side to draw air out of the engine compartment. The muscular fenders and wheel arches sweep back into the sides.
In profile, the Flextreme GT/E is distinguished by innovative, stubbed C-pillars. This floating design allows the glasshouse to be extended rearwards under the arching roofline, emphasizing the flowing lines of the side. Vauxhall’s signature blade motif is reinterpreted in a swooping swage line from the base of the C-pillar into the lower front fender.
Access to the cabin is enhanced by the adoption of rear-hinged rear doors, an evolution of the FlexDoors concept from the new generation Meriva. To preserve the clean exterior, all door handles are replaced by light sensors. These trigger the doors when covered by a hand. To reduce air turbulence, exterior front door mirrors are also absent, replaced by small camera pods in the base of the A-pillars.
At the rear, a strong shoulder line embraces sculpted wheel arches that further emphasize the Flextreme GT/E’s wide, ground-hugging stance. The coupé look is completed by a steeply raked tailgate, carrying wing-shaped LED lights that echo the front headlamps.
Taking a leaf from the Insignia Sports Tourer’s book, the tailgate has a wraparound design for improved trunk access, enhanced by a convex deep glass screen to improve airflow.
The transparency of the fixed glass panel in the centre of the roof is adaptive, allowing sunlight to warm the interior in the cold of winter, but darkening for coolness in summer. A duct at the rear edge of the roof is for additional cooling of the battery and electronic components.
Integral to the Flextreme GT/E’s dramatic looks is the efficiency of the design execution. The small frontal area, low roof height (51.5”) and a flat, enclosed underbody enable the car to cleave the air with minimum disturbance.
The 21” alloy wheels are relatively narrow to reduce wind resistance, fitted with 195/45, low rolling resistance tires. Clear, flush-mounted trim inserts also minimize turbulence.
The small front intake improves airflow around the nose of the car and the underbody sweeps up, venturi-like, at the rear to further reduce drag.
The Flextreme GT/E also explores the potential for active shape shifting. At speeds above 30mph, a vertical panel extends along the body from the air extraction slot behind each rear wheel arch. These side spoilers guide high-speed airflow around the rear corners of the car, further reducing turbulence.
Mass reduction measures for the body include the use of lightweight, carbon composite outer panels, polycarbonate window glazing and aluminum alloy structural components. Compared with conventional materials, these offer a 40 per cent weight saving which further contributes to reduced energy consumption and an increased driving range.
The Flextreme GT/E concept includes the groundbreaking E-REV drive system, already developed for the Vauxhall Ampera. Despite its greater size and a maximum speed of more than 125mph, the Flextreme GT/E is estimated to offer performance similar to that of the Ampera: a battery-powered driving range of up to 40 miles – with zero emissions – and a total range of over 300 miles.
Average fuel consumption is estimated at 175mpg (145mpg US), with CO2 emissions of less than 40g/km. Unlike a hybrid vehicle, the wheels of the Flextreme GT/E are powered at all times by electricity. For typical journeys up to 40 miles, energy is supplied by a T-shaped lithium-ion battery pack under the floor and rear seat.
However, unlike a battery-only electric vehicle, the Flextreme GT/E eliminates range anxiety with a small gasoline engine/generator, which seamlessly engages to provide electricity whenever the battery becomes depleted. In this mode, the driving range is extended to more than 300 miles, until the plug-in battery pack can be recharged or the car is refueled.
The motor in the electric drive unit delivers a substantial 272 lb-ft of instant torque, giving lively performance and projected zero to 62mph acceleration in less than nine seconds.