Natural Gas Engine Mercedes-Benz M 447hG with Exhaust Emissions Lower than 50% Euro II

The growing consciousness of the need to develop environmentally friendly technologies, finding alternatives for petrol as energy source, led to a significant growth of the interest to use natural gas as fuel in urban transportation.

In the beginning of the decade of 1990 Mercedes Benz AG decided to offer an urban bus powered by the CNG-engine M447hG, which should have exhaust emission levels below 50% of Euro II. It is a horizontal engine with six in-line cylinders, using stoichiometric technology (λ=1) and a three-way catalyst. With 12 l displacement, the rated power is 175 kW @ 2200 min^-1, and the maximum torque 880 Nm @ 1000 min^-1.