The 4.7-meter long Flextreme GT/E concept illustrates how extended-range electric vehicle (E-REV) technology can be plugged into large or mid-size vehicles, as well as compact cars such as the upcoming Ampera.
Opel/Vauxhall calls the strategy underpinning Flextreme GT/E, ‘e-mobility unlimited’, which will effectively adapt the highly efficient E-REV drive system to vehicles across all market segments. In other words, the Flextreme GT/E concept shows that size really doesn’t matter when it comes to driving a car with zero C02 emissions.
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 front and rear, a distinctive nose and grille, ‘floating’ C-pillars and muscular, sculptured bodywork.
The doors are rear hinged, much like the FlexDoors from the new Opel/Vauxhall Meriva, while the car does away with all door handles and side mirrors and instead relies on technology, with sensors replacing the handles and small cameras replacing the wing mirrors.
At the rear, a strong shoulder line embraces sculpted wheel-arches that further emphasise the Flextreme GT/E’s wide, ground-hugging stance. The coupé look is completed by a steeply raked tailgate, carrying wing-shaped LED light units which echo the form of the front headlamps. And taking a leaf from the Insignia Sports Tourer’s book, the tailgate has a wraparound design for improved boot access, enhanced by a convex deep glass screen to improve airflow.
Integral to the Flextreme GT/E expressive looks is the efficiency of the design execution. The small frontal area, low roof height (1308 mm) and a flat, enclosed underbody all enable the car to cleave the air with a minimum of disturbance.
A series of measures optimize airflow management. The 21-inch alloy wheels are relatively narrow, to reduce wind resistance, and fitted with 195/45, low rolling resistance tires. Clear, flush-mounted trim inserts also minimize air turbulence.
The minimal 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 50 km/h, a vertical panel extends along the body from the air extraction slot behind each rear wheel-arch. These 350 mm-long side spoilers guide high-speed airflow around the rear corners of the car, further reducing the amount of 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 to conventional materials, these offer a 40 percent weight saving which further contributes to reduced energy consumption and an increased driving range.
The Flextreme GT/E concept also includes the groundbreaking E-REV drive system, already developed for the Opel/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 CO2 tailpipe emissions – and a total range of over 300 miles. Average fuel consumption is estimated at 175mpg UK (146mpg U.S.), 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 located under the floor and rear seat.
However, unlike a battery-only electric vehicle, the Flextreme GT/E eliminates any possibility of range anxiety through fear of being stranded without power. The small petrol engine/generator is seamlessly engaged to provide electricity whenever the battery’s supply 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 370Nm of instant torque, giving lively performance and projected zero to 62mph acceleration in less than nine seconds.[wzslider height=”400″ lightbox=”true”]