Gas
Gas can be used for fuelling heavy vehicles, although the technology has some limitations. Biogas is a renewable fuel with good emission characteristics.
Gas is favoured by some operators and also some authorities for several reasons. Emissions are low and noise reduced, but since the engine operates according to the Otto principle, efficiency is lower than for a diesel engine.
With biogas supplied locally, e.g. from waste or sewage plants, gas operation has excellent emission reduction properties. The carbon dioxide reduction is then almost 100%. Natural gas is not an ideal replacement for diesel fuel since it is fossil, although emissions of regulated substances are handily reduced.
The main drawbacks are the need to carry gas onboard the vehicle in heavy and bulky gas tanks and the complexity of the supply infrastructure. Hence, weight limitations may give a short operating range. Gas is unlikely to play a major role in long-haulage because of these limitations.
