This is VW’s radical, lightweight, VW XL1 which promises an EU-certified economy of 314mpg and 21g/km CO2 emissions when it goes into limited production later this year following its Geneva motor show reveal.
Powered by a 47bhp two-cylinder 800cc TDI engine backed up by a 27bhp electric motor and 5.5kWh battery pack, the two-seat car is claimed to have a Cd rating of just 0.189.
The upshot is that the plug-in hybrid XL1 is probably the most economical and most aerodynamically efficient production car of all time.
Weighing just 795kg, the XL1 is some 3.8m long and 1.66m wide, which means it is only marginally smaller than a VW Polo supermini. However, it is only 1.15m high, some 129mm lower than a Boxster. VW says the XL1 has its top speed limited to 99.4mph, but that it can hit 62mph in just 12.7sec. It uses aluminium double wishbone front suspension, a semi-trailing link suspension at the rear, carbonfibre reinforced plastic anti-roll bars and ceramic brake discs.
The XL1 can travel for 31 miles just on battery power alone and has a claimed range of 310 miles on diesel and battery power combined, despite having a tiny 10-litre fuel tank.
Rough calculations suggest that the XL1 is capable of a real-world 127mpg in ideal conditions, a product of the car’s 795kg kerb weight, its very slippery body and wind-cheating and low resistance narrow tyres on magnesium wheels, which measure just 115/80 at the front and 145/55 at the rear. A guide to the XL1’s efficiency is that VW claims it requires just 8.3bhp to be able to maintain a steady 62mph cruise.
The hybrid system’s electric motor and its dedicated clutch are fitted between the 800cc two-cylinder diesel engine and the XL1’s seven-speed DSG gearbox. The lithium-ion battery is mounted in the nose of the car and can be recharged when the car is braking and coasting.
In pure electric mode, the engine’s clutch disengages and the motor shuts down. The engine is brought back to life via what VW calls ‘pulse starting’, where the electric motor spins up to high speed and is coupled back to the engine, accelerating the idled engine to the revolving speed required for smooth starting.
The extreme weight-saving measures include using carbonfibre reinforced plastic for the body, the skin of which is just 1.2mm thick. Aluminium crash structures are used front and rear and as crash beams in the doors, to absorb impact forces.
The windscreen is just 3.2mm thick. VW says the XL1’s construction breaks down into a 227kg drivetrain (including the battery), 153kg running gear, 105kg electrical system, 80kg of on-board equipment, such as seats and instruments, and a body that weighs 230kg. Even the dashboard is made from a lightweight wood fibre material that’s just 1.4mm thick.
The first production run will be of 50 cars, which are fully homologated for sale in Europe. After that, sources say the XL1 will be built to meet demand, though VW has yet to give any clue about the likely price.
Read our first drive of the Volkswagen XL1 here
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