Volkswagen has just presented a new edition of its Up! mini called "Eco", which features a modified version of the regular model's 1.0-liter three-cylinder petrol engine that can run on Compressed Natural Gas, or CNG for short.
CNG is a promising alternative fuel to gasoline that has caught up with many European consumers.
Among the many benefits of this fuel is that it has a higher energy content than petrol or diesel as 1.0 kg of natural gas is equivalent to 1.3 litres of diesel or 1.5 litres of petrol. According to VW, the energy content of 1.0 kg natural gas amounts to 11.69 kW, while the associated quantity of diesel yields 9.86 kWh and of petrol, 8.77 kWh.
In addition, engines developed to run on natural gas can also use regular gasoline and alternative fuels such as renewable biomethane.
Volkswagen has equipped with the Up! Eco with three subfloor tanks, the first of which is used to store CNG (35 litres) and is located in front of the rear axle together with the reserve petrol tank (10 litres), while the third tank for CNG storage (37 litres) utilizes the space of the spare wheel.
"Since the entire EcoFuel system could be integrated entirely within the vehicle structure, usable space is not restricted in any way except for the lack of a spare wheel recess," says Volkswagen.
When powered by CNG, the 1.0-liter unit produces 67hp (68PS) at 6,200 rpm and peak torque of 90Nm (66 lb-ft) at 3,200 rpm, allowing the car to reach 100km/h (62mph) in 16.3 seconds and top out at 164km/h (102mph).
The German automaker has also fitted the Eco model with its suite of BlueMotion Technologies, including Stop/Start system, battery regeneration and tires optimized for low rolling resistance.
The result is a low combined fuel consumption of 2.9 kg or 4.4 m3 of natural gas per 100 km with CO2 emissions of just 79 g/km.
VW claims that taking into account the average price of natural gas in Germany in November 2012, the Up! Eco incurs fuel costs of just 3 euros (US$3.9) per 100km, which it says, "represents a fuel cost level that is over 50 per cent lower than that of a comparable petrol engine".
In Germany, the Up! Eco lineup starts at €12,950 (US$16,800 at today's rates), with VW noting that buyers can receive a government subsidy of over €1,000 (US$1,290).