The Passat TSI Ecofuel that first took center stage in the 2008 Geneva Car Show is powered by a 148 horsepower engine that runs on gasoline or natural gas. The car is designed to be monovalent and the car manufacturer does not have any plans to include an option of manual switchover from natural gas to gasoline. The gasoline tank is just there to serve as a fuel reserve.

The fuel consumption for the Passat TSI Ecofuel is an impressive 100 kilometers for every 4.38 kilograms of autogas. Carbon dioxide emissions are measured at 119 g/km making the car Euro-5 compliant.

If the Passat will use up the 22 kg of autogas stored in its tanks and the 31 L of gasoline, the vehicle can run for almost 900 km or 559 miles. The natural gas is enough for traveling a distance of 500 km.

The Golf BiFuel has a 97 horsepower power plant that can run in either gasoline or autogas. The car has a factory-built autogas system. The vehicle was crush tested thinking of the safety of the car in combination with its fuel tanks. The Golf BiFuel is also specifically designed to run on autogas and is far more durable than converted gas engines.

Pure autogas mode of the Golf BiFuel can bring someone to a destination of 420 kilometers or 261 miles. Combined with the 55 L gas tank, the car can go as far as 1100 kilometers or 684 miles.