<Li> Vehicle electronic control systems that automatically maintain distances between vehicles on motorways / freeways that reduce ripple back braking, and consequent re-acceleration . </Li> <Li> Time - optimized piston path, to capture energy from hot gases in the cylinders when they are at their highest temperatures </Li> <Li> sterling hybrid battery vehicle </Li> <P> Many aftermarket consumer products exist that are purported to increase fuel economy; many of these claims have been discredited . In the United States, the Environmental Protection Agency maintains a list of devices that have been tested by independent laboratories and makes the test results available to the public . </P>

What is the average fuel consumption in kilometers per litre