VW L1 world's most efficient hybrid

The Volkswagen L1 unveiled today at Frankfurt Motor Show claims a fuel figure of 1.38L/100km, which puts it far ahead of the Toyota Prius, Mini Diesel, Honda Civic Hybrid and even the microhybrid Smart. Emissions are similarly impressive at 36gm/km — less than half the Prius which puts out 89gm/km. Sadly, the the L1 is a concept. But it's one on which Volkswagen intends to build future technology.

It echoes an earlier concept from seven years ago, the Volkswagen 1-Litre, that then-chairman of VW's board, Dr Ferdinand Piech drove from Wolfsburg to Hamburg. At that stage it was promised for production in 2010, but never appeared.

The second generation in Frankfurt is a tiny 1+1 seater uses a 800cc two-cylinder turbodiesel with common rail injection, coupled to an electric motor that draws from a lithium-ion battery. Maximum outputs with the two working together are 29kW of power and 100Nm of torque, which is delivered via a seven-speed twin-clutch DSG.

The in-line seating allows for an extremely streamlined shape for the lightweight 380kg carbon-fibre body, with an aerodynamic drag figure of 0.195 — the Prius is 0.25 — helped by clever tricks such as replacing the side mirrors with tiny cameras that project images onto twin screens in the dash, while fuel consumption is further helped by low rolling-resistance tyres. But the effort to stay trim hasn´t meant sacrificing safety, with the car fitted with anti-skid brakes and stability program.

The tiny two-seater nearly stole the thunder in the Volkswagen Group hall at Frankfurt Motor show today, getting as much attention as the stablemate Audi R8 Spyder and e-tron nearby. And it's bound to build attention for VW´s march towards the holy grail of 'sustainable mobility'.

"The L1 will spearhead the technical innovation at Volkswagen," the brand's board member responsible for development, Dr Ulrich Hackenburg, says. "This car is a technology driver for (VW fuel efficiency program) Bluemotion — we will use it to learn about what technology can help, and what to put into production."

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