The Frankfurt Motor Show is playing host to a staggering array of weird and wonderful concept cars this week, many of which are geared around green credentials. Notably among them is the new concept from Volkswagen- the L1 – a diesel-electric hybrid vehicle constructed from aluminium and carbon fibre weighing just 380 kg and capable of returning a staggering 189 mpg on the combined cycle while emitting just 39 g/km of CO2.
Although the L1 is only a two seater, the combination of a fuel efficient diesel engine with a hybrid system means that for the first time, a hybrid can reach new highs in miles to the gallon ratings. Currently only petrol hybrids are mass produced, but the L1 could be the start of an all new geneartion super-efficient cars.
The L1 combines this new diesel hybrid technology with other wonderful little tweaks to push its fuel sipping tendencies over the edge. With a side-hinging, electrically operated canopy instead of doors through which the occupants enter, the L1 can maximises its aerodynamic efficiency. The result is a remarkable co-efficient of drag figure of just 0.195.
But not only is the body extremely aerodynamic but it’s also very light and strong. The safety cell, constructed from carbon fibre reinforced plastic, weighs just 124 kg. At 3,813 mm in length, the L1 Concept is comparable to the Fox yet at just 1,143 mm in height it’s as low as a Lamborghini Murcielago. Its width, at just 1,200 mm, is narrower than any conventional car on sale today.
The driving environment shares more in common with an aircraft than a car. The adjustable front seat is thin and constructed from carbon while the rear passenger sits in a fixed seat built into the monocoque. The driver has an excellent view of the road and sits behind an instrument panel set into the body of the car. The rear view mirror is replaced by an organic light-emitting diode display while the main controls for the operation of the vehicle are grouped around the steering wheel.
Every element of the L1 Concept is intended to maximise efficiency. At its heart is a tiny 800 cc two-cylinder common rail, direct injection TDI engine. In ‘ECO’ mode the engine develops 27 PS at 4,000 rpm, in ‘Sport’ mode this rises to 29 PS and 74 lbs ft of torque developed at 1,900 rpm.
The modest kerb weight of the L1 Concept linked to efficient aerodynamics mean that it is capable of accelerating to 62 mph from rest in 14.3 seconds before reaching a top speed of 99 mph. Despite having only a 10-litre fuel tank the L1 Concept’s incredible efficiency means that it is capable of travelling 416 miles between stops.
The 800 cc engine is derived from the 1.6-litre TDI engine found in the new Golf BlueMotion, also making its debut at the Frankfurt Show. The two have identical cylinder spacing, bore and stroke as well as exhaust gas recirculation and diesel particulate filters to ensure they meet and exceed the Euro-5 emissions regulations.
Under normal conditions the 14 PS electric motor is inactive, only engaging when additional acceleration is required, delivering 40 per cent extra torque. In addition, the electric motor can take over from the engine to power the L1 Concept for short distances.
The L1 Concept draws inspiration from the original 1-litre car, unveiled in April 2002 when Dr. Ferdinand Piëch, then Chairman of the Board of Management, drove the concept between Wolfsburg and Hamburg. At that time productionising the carbon fibre reinforced plastic body was simply not viable. With modern production processes, Volkswagen no say that large-scale manufacture of such structures is now possible. But no news yet of when we might see a production ready version of the little L1.
