On the basis of our fuel and drivetrain strategy, we are pointing the way towards sustainable mobility and contributing to cutting global CO2 emissions. We are also reducing our local nitrous oxide and particulate emissions and lowering our dependence on oil.
Our strategic considerations are aimed at the use of renewable CO2-neutral energy sources, though we also focus on optimizing the properties of conventional, oil-derived fuels and their emissions.
As part of our drivetrain strategy, our use of TSI technology – a petrol direct injection with turbo- or supercharger – builds on the successful TDI engine concept. TSI engines have consumption levels of up to 20% less than other fuel injection engines, while retaining the same driving dynamics. A further example of highly efficient drive technology is the direct shift gearbox (DSG), which is considerably more effective than conventional automatic gearboxes, offering fuel consumption gains of around 15%. Our natural gas models, which are also capable of running on petrol, emit up to 25% less CO2 in natural gas mode and eliminate sulfur dioxide, soot and other particulate emissions almost completely. Following the Touran EcoFuel* and Caddy EcoFuel*, we presented the Passat TSI EcoFuel in 2008, the first turbo direct-injection engine designed to run on natural gas.
Hybrid technology will play a central role in our drivetrain strategy in the medium term in addition to petrol and diesel engines. We have entered into strategic partnerships to integrate hybrid drives in future series products.
THE VOLKSWAGEN GROUP’S INVOLVEMENT IN REDUCING FLEET CONSUMPTION
With regard to engine development, petrol and diesel engines are becoming increasingly similar. Following the introduction of direct injection in petrol engines, which marked a milestone in engine development, further developments in combustion processes also highlight the growing similarity between the two technologies. On the diesel side, work continues on homogeneous mixture formation as in petrol engines. Meanwhile, attempts are underway to make the spark plugs on petrol engines superfluous, at least in certain parts of the engine map, using a homogeneous compression ignition system. Volkswagen has developed a new combustion system for this based on today’s diesel engines that allows limited pollutants such as nitrous oxides and particulates to be reduced, while at the same time significantly improving efficiency and reducing fuel consumption.
In the long term, the main focus of our drivetrain strategy will be on emission-free electric drives, which we believe will be the most important development in the future of automobility. Although electric vehicles have the best energy rating, their low range does not yet satisfy customer requirements: today’s storage technology only allows them to negotiate a maximum distance of 100 km.
Pure electric traction will therefore not become possible until there have been significant advances in fundamental research into battery storage technology. We intensified cooperative arrangements with battery manufacturers in 2008 for this purpose. Last year we presented an option for emission-free mobility in everyday use with the Golf twinDRIVE, which is participating in the federal government’s “Fleet trial: electric drive vehicles” (“Flottenversuch Elektromobilität”) initiative. In addition to innovative concepts for plug-in hybrids like the twinDRIVE, Volkswagen is also devoting itself to developing energy supply concepts for the nascent e-mobility based on sustainably generated power.
One focus of our fuel strategy is research into biofuels, principally second-generation biofuels, which we refer to collectively as “SunFuel”. These harbor considerable potential in terms of reducing CO2, do not represent competition for food production and are compatible with the existing infrastructure. SunEthanol is one example of a biofuel optimized for petrol engines. It is derived from straw using a biochemical process developed by IOGEN. SunDiesel, the corresponding synthetic fuel for diesel engines, can be manufactured from a number of primary sources such as biomass or residual biomaterials. The quality and chemical composition of the end product do not depend on those of the primary energy used. Synthetic fuels can be used in both current and future combustion engines. SunFuel can also be adapted to the requirements of enhanced engine technology more easily than conventional fuels. Due to its purity of composition and the fact that its properties can be tailored, it offers considerable potential for further reducing harmful emissions. Furthermore, it can be ideally adapted to new combustion systems, thereby further increasing such systems’ potential in terms of fuel consumption and exhaust emissions.
We believe that the importance of local emission-free mobility will grow in the long term. This may take the form of battery-powered electric vehicles or vehicles with a fuel cell drive, for example. At present, vehicles with a hydrogen-based fuel cell are the only means of achieving emission-free mobility over an acceptable range. Our research unit has developed a high-temperature fuel cell that is one of a kind and, thanks to the use of electrodes that allow a higher operating temperature for fuel cells, is more efficient, smaller and also more economical than existing fuel cells.