Tokyo: VW slots XL-1 powertrain into the up! image

Volkswagen’s pledge to bring a so-called 1.0-litre car – as in litres of fuel needed to cover 100 kilometres, rather than engine capacity – to market came a step nearer at Tokyo with the global introduction of the Twin up!

This plug-in hybrid version of VW’s small city runabout uses a diesel-electric powertrain similar to that in the futuristic XL-1 experimental car revealed three years ago.

The major difference is that the Twin up! has a more powerful electric motor and a greater-capacity lithium-ion battery to cope with its greater weight (1,205kg).

The motor has been uprated from 20kW to 35, while the battery storage is 8.6kWh instead of 5.5. The front of the combustion-engined up! has had to be lengthened by 30mm so that the powertrain will fit comfortably under the bonnet. “It was easier to change the car than the transmission,” VW says.

The company is quoting fuel consumption of nearly 256mpg for the car, compared with just under 314mpg for the XL-1. The respective CO2 figures are 27g/km against 21g/km. The powertrain pairs a 50bhp, 800cc two-cylinder diesel engine – half the engine in a diesel Golf – with the electric motor and a seven-speed DSG gearbox.

The car can run in full electric mode for up to 37 miles at a maximum 77mph, as a hybrid with a combined 75bhp and 215Nm of torque, or as a diesel at speeds of 90mph. It has a range of close to 700 miles using both power sources.

Charging the battery from empty takes two hours using a standard domestic socket. Battery power can be reserved until needed, such as when entering cities where there are emissions taxes.

At the moment the Twin up! is only a study, but it has been designed so that it can be built on the same production line as the combustion-engined and electric versions of the up! if there is sufficient demand to make a business case for it.

“The XL-1 was a lighthouse car for us and we wanted to show that the lighthouse could be turned into a regular production vehicle,” VW says. “If people are interested we could maybe go the next step, but it wouldn’t be very cheap.”

However, VW will bring a Golf using similar technology to market, and is likely to show it at Geneva next spring. It will use the company’s 1.4-litre TSI petrol engine with an electric motor. The target economy figure is 188mpg.

text: Headlineauto co uk