Audi opens a new chapter in clean motoring later this year with the launch in Germany of the five-door A3 Sportback g-tron – fuelled by C02-neutral e-gas (CNG) which is being produced at a new plant in Werlte, Germany.
The CNG is housed in two tanks under the rear floor. Each can contain seven kilograms of CNG which is pressurized to a maximum of 200 bar. Audi says the CNG tanks are made from a combination of carbon fibre, polyamide polymer and glass-reinforced poymer and are 27kgs lighter than a conventional fuel tank.
An electronic gas pressure regulator reduces the gas pressure in two stages on the way to the injectors in the engine where it is supplied at a low pressure for low-speed motoring and a higher pressure for fast going. When the gas pressure drops below 10 bar the Audi A3 Sportback g-tron switches to the petrol engine.
The gas tanks provide a range of 400kms and the patrol engine delivers 900kms giving a total range between re-fills of 1300kms. There are two filler necks under the fuel flap and after re-fuelling (or when the ambient temperature is low) the engine starts with the petrol engine then switches to gas.
Uner the bonnet is a slightly modified version of Audi’s 81kW/200Nm 1.4 TFSI engine. Audi says the CNG version of the A3 Sportback provides performance virtually identical to the petrol version – zero to 100km/h in 11.0 seconds.
The C02 from Audi’s e-gas plant in Welte is a waste product from a nearby biogas plant operated by German power utility company EWE. The C02 would otherwise be emitted as a pollutant into the air.
Audi says its plant has the capacity to fuel 1,500 Audi A3 Sportback g-tron vehicles every year.
