Assessing current vehicle performance and simulating the performance of hydrogen and hybrid cars

The on-the-road performance of passenger cars are often discussed in terms of kilometres driven per MJ (or other unit of energy). This does not do justice to the different payloads that different cars are certified to carry, perhaps considering the poor correlation between required, actually used and available passenger and cargo space characterising the vehicle choice of many passenger car owners. Campaigns have occasionally been directed at increasing customer usage of the available payload (better trip planning, pool arrangements), but automobile sales material often mentions only km/MJ overall performance, if anything at all related to energy efficiency (mentioning energy performance is mandatory in some European countries, but mostly not done in North America).

Below, I present performance data in terms of transport work carried out, such as kilometres times maximum payload that may be obtained per unit of energy input. In addition to being a prerequisite for encouraging better payload utilisation, this also allows transport modes other than passenger cars to be compared on a equal footing. Such comparisons are made for passenger cars, motorcycles, buses, trucks, rail-based trains, ships and aircraft carriers, with payloads that can comprise different rations of passenger and cargo transportation, as the payload is in all cases expressed in kilograms. This transport work performance measure may be expressed in terms of the maximum certified payload, or it may be expressed in terms of the average actual payload, in order to discuss the role of the payload utilisation fraction (such as seat occupancy for passenger modes)

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