The gains in efficiency and hence CO2 output from fine-tuning an engine (either in the operational or design stage) are measured as a few % only and come at a considerable cost in time and high-tech parts. You can gain 50% reduction in fuel usage by reducing engine capicity from 5 litres to 1.5 litres and vehicle weight from ~2 tonnes to <1 tonne AND save money while you do it. Look at Euopean cars vs US as an example of what's possible.
In a sense, it's the reverse of the evolution that has occurred in vehicle and engine size over the last 100 years, but coupled with the advances in material science, design concepts, and combustion processes, it would result in an equally safe vehicle fleet that consumes a lot less hydrocarbon fuel, with equal top speed, but reduced acceleration.
Personally, If I want acceleration, I'll ride my motorcycle. It runs close second to a Bugatti Veyron (for the first 1/4 mile, anyway), and is a damn sight cheaper in dollars and resources. It also firmly puts the onus for safety in my hands and the risk of injury is stacked heavily against me, rather than driving a monster car that can crush others.
Current Events » in reply to re: Efficiency
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