What is the power and range of a heavy duty (HD)NGV?
Typical HD diesel city buses run about 300 km per day and consume 40 to 60 litres per 100 km. Thus diesel tanks of 250 to 300 L provide adequate supply for two days light duty (LD) and one day HD operation. The total weight of the on-board installation would be about 300 kg. When using CNG the same types of operation would result in a fuel consumption of 45 to 65 kg of gas per 100 km. To achieve the same range as the diesel vehicle the gas quantity would be about 300 kg with a margin of safety (remember there may not be many compressor stations available in case of running out of fuel). With standard steel 120 litre cylinders each weighing about 120 kg and each holding about 30 kg gas when fully charged – a total 10 cylinders is required, resulting in a total mounted weight of about 1.4 tonnes including fittings etc. In regard to power loss, this depends very much on how the engine is converted to gas. Since the process involves considerable modification if the diesel engine is convert
