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New technology development has always been a key competitive factor in the automotive industry. There have been many advances in all areas of the vehicle, especially in the power train. Most advances replace an existing function with an improved function: fuel injectors deliver fuel in a more controlled and precise manner than carburetors, CVT transmissions offer infinitely variable speed ratio compared to the limited fixed ratios of step-shift transmissions, etc. When developing technologies, the performance specification starts with the capabilities of the previous system, and then is expanded to take advantage of the new features. It is these new features, sometime un-intended consequences, that can offer real breaks in development paths. One such new technology is the hybrid power train. A hybrid power train is new technology power train with two power sources, typically an internal combustion engine and a battery (although other types exist).

The transition towards a ‘Green Economy’ puts pressure on automakers to improve the fuel economy of their vehicles. Fuel economy is complicated vehicle attribute impacted by a large number of factors, not limited to vehicle weight, rolling resistance, aerodynamic drag, engine efficiency, drive train losses, accessory loading, and performance targets embodied in the controls strategy. Due to the number and complexity of contributing factors, fuel economy benchmarking, target setting and technology evaluation can be difficult. This paper introduces two new vehicle attributes: miles per kilowatt-hour (mpk) and kilowatt-hours per gallon (kpg) which, when multiplied together, calculate mpg. These parameters are derived from emissions and fuel economy certification data posted by the EPA on their website. This paper then shows how these parameters can be used to characterize and benchmark vehicles, set targets for new vehicles, and project future technology trends.