BMW Vision EfficientDynamics Concept
BMW sees technical innovations reducing both emissions and fuel consumption as an elementary part of the brand’s product strategy, just like vehicle concepts enhancing the Sheer Driving Pleasure so typical of BMW as a lasting, sustained experience.
Now the BMW Vision EfficientDynamics concept car clearly demonstrates that these objectives expressed through the BMW EfficientDynamics development strategy are fully compatible with the most demanding reduction in fuel consumption and emissions complying in full with future requirements. Conceived as a 2+2-seater with plug-in full-hybrid technology, this unique car is able to combine the performance of a BMW M Car with a standard of fuel economy and emission management exceeding even the current level achieved by the latest small cars in the market.
This outstanding result is made possible by the consistent integration of BMW ActiveHybrid components, their combination with an extremely economical combustion engine, and the outstanding aerodynamic qualities of the BMW Vision EfficientDynamics concept car.
BMW Vision EfficientDynamics is the result of an all-inclusive development process starting from a clean sheet of paper. This ensures an improvement of both efficiency and driving pleasure far exceeding the sum total of all individual components and technologies, and is also borne out in the very emotional design of this unique concept car. BMW Vision EfficientDynamics is therefore an unprecedented sports car offering fascinating perspectives for the future of Sheer Driving Pleasure combined in full harmony with maximum efficiency.
The combustion engine is a cutting-edge turbodiesel featured for the first time in the BMW Vision EfficientDynamics concept car. Displacing 1.5 litres on three cylinders, the engine consistently follows the downsizing principle using relatively small engine capacity combined with a turbocharger to reduce fuel consumption.
Through its compact dimensions, the three-cylinder fits conveniently in front of the rear axle like in an agile mid-engined sports car, despite the two seats at the rear. Fuel is injected by the latest generation of common-rail direct injection, the turbocharger features variable intake geometry for maximum efficiency.
The power delivered by the turbodiesel in conveyed to the rear axle by means of a double-clutch gearbox. This advanced transmission technology already offering a particularly dynamic driving experience in BMW’s unusually sporting production cars, allows the driver to shift gears without the slightest interruption of power and traction.
BMW Vision EfficientDynamics comes with a newly developed, minimum consumption version of BMW’s direct-clutch gearbox with six speeds for maximum efficiency and flexibility.
The combustion engine is supplemented by two electric motors. Consistently applying the BMW ActiveHybrid strategy, BMW’s development engineers followed the principle of “Best of Hybrid”, choosing the optimum combination of a hybrid synchronous motor on the front axle and a full-hybrid system at the rear. Through the specific configuration of the system as an advanced hybrid ideal for practical use on the road, the driver benefits from the extra efficiency of the electric motors over a far wider speed range than with a conventional hybrid car.
The rear axle comes with a second-generation full-hybrid system corresponding to the technology introduced for the first time in the BMW ActiveHybrid 7 production model. Running as an electric motor, the compact electric power unit positioned between the combustion engine and the double-clutch gearbox develops a consistent 25 kW and is able to reach a peak of up to 38 kW. Maximum torque, again, is 290 Nm or 214 lb-ft, the power developed in this way serving, depending on driving conditions, either to support the combustion engine or for all-electric motoring.
In overrun and when applying the brakes the electric motor acts as a generator feeding electric power to the lithium-polymer battery in the car. The electric energy developed in this way is therefore generated without any additional consumption of fuel, raising the principle of Brake Energy Regeneration already featured in BMW’s current models to an even higher and significantly more efficient level. Energy wasted on the brakes of a conventional car is thus saved within the new power system for subsequent use in driving the car.
A second electric motor acts on the front axle. This power unit, a hybrid synchronous motor, offers permanent output of 60 kW and peak torque of 220 Newton-metres or 162 lb-ft. Extra power of 84 kW is available for a period of up to 30 seconds and for 10 seconds the electric motor is even able to develop 104 kW. Power is transmitted through a two-stage, single-speed reduced-ratio gearbox.
BMW Vision EfficientDynamics is able to run completely under electric power, with the power of the turbodiesel engine alone, or through an infinite combination of the three power sources. Depending on driving conditions and the driver’s particular requirements, the two electric motors may be used both for accelerating and for regenerating energy when applying the brakes and in overrun.
This principle ensures a high level of efficient energy management, with the charge status of the lithium-polymer battery constantly remaining within the optimum range. When accelerating the electric motors help to boost the car for even greater performance, ensuring a spontaneous and direct response and a significant reduction in fuel consumption. For a short time, for example when overtaking, the cumulative maximum output of all three power units increases to 262 kW/356 hp, with maximum torque generated by the three power units reaching 800 Newton-metres/590 lb-ft.
The power delivered by the three power units gives the BMW Vision EfficientDynamics concept car a level of dynamic performance far superior to anything provided so far by any hybrid vehicle. Indeed, the performance and consumption figures determined by standardized computer simulations show an exceptionally good balance of driving pleasure and fuel economy even for a hybrid. Acceleration from a standstill to 100 km/h, for example, comes in just 4.8 seconds and the car’s top speed would be over 250 km/h or 155 mph, requiring electrical limitation of top speed in accordance with BMW’s corporate philosophy through electronic engine control now also on a full-hybrid sports car.
The objective to develop a vehicle offering the performance of a BMW M Car combined with supreme all-round efficiency therefore comes to bear completely and without the slightest restriction in BMW Vision EfficientDynamics.
BMW Vision EfficientDynamics also takes a new approach in its design and streamlining, the body and the interior clearly expressing the unique combination of supreme efficiency and the sporting performance so typical of the brand. Following the design language so characteristic of BMW, this unprecedented concept car clearly visualises both highly efficient aerodynamics and consistent lightweight construction.
In its design, BMW Vision EfficientDynamics differs significantly from the usual low-emission cars seen so far. And since the principle of “form follows function” is not reduced in this case just to the overall look of the car, but rather embraces each and every detail, BMW Vision EfficientDynamics combines unique aesthetic appeal with a highly emotional impact. Through its design alone, therefore, BMW Vision EfficientDynamics clearly proves that Sheer Driving Pleasure in typical BMW style may also be offered without restrictions in a brand-new, innovative car concept.
Measuring only 1.24 metres or 48.8" in height and boasting a sweeping, arch-like roofline, BMW Vision EfficientDynamics offers the slender silhouette of a classic Gran Turismo. With the combustion engine fitted in front of the rear axle, the designers have furthermore succeeded in giving the car a very low and sleek front end, with the fl ow of air depending on driving conditions being further smoothened by active louvers in the radiator closing completely whenever the need for cooling air is relatively low.
This efficient function follows in the footsteps of the active air flap control already used as a feature of BMW EfficientDynamics in many of BMW’s current production models. And as a further highlight, BMW Vision EfficientDynamics guides air smoothly and exactly as required into the car through an active air intake at the front.
In the design of the interior, innovative layering technology provides an unprecedented symbiosis of function and stylish shapes intentionally reduced to a minimum, consistently implementing and visualizing the lightweight principle also inside the car.
Specific components such as the central air vent not only serving to enhance motoring comfort but also acting as part of the cockpit, perform several functions in one. This multi-functionality is then presented visibly within the car, the use of particularly sophisticated materials providing a highly attractive combination of innovation in technology and quality clear to the eye and the touch of the surface.
This interaction of lightweight construction and individual well-being also comes out clearly in the design of the controls and switches, with a leather band, for example, running round the aluminium gear selector lever on the centre console.
The doors on BMW Vision EfficientDynamics open up like gullwings, turning on pivots in the front roof column at the level of the side direction indicators. Since the car has no B-pillars, the large door cutouts ensure convenient entry also to the rear seats. The pivots on the doors also provide the base for the exterior mirrors, thus forming an ideal combination of function and aesthetic design.
The structure of the doors is also characterized by several layers of materials on top of one another and the optical and functional symbiosis of the interior and exterior this technology is able to offer. Made up of three layers, the overall structure comprises the outer glass surface, an interim load-bearing layer, and the interior cover with its particularly smooth shapes and flowing forms clearly visible to the passengers, layering technology again, therefore, opening up new perspectives.
Source: BMW press