For those of you of the cab riding persuasion in green American cities, you should be aware of this trick because of all those stops and starts from signs and lights.

Hybrid cabs get all quiet when they come to a complete stop because their engines shut off. Awkward silence ensues, either leading to an interesting story from an interesting driver, a creepy story from a creepy driver, or a terrible practice monologue for an aspiring stand-up comic.

This engine shutdown (as uncomfortable as it may be) leads to real savings in fuel consumption; unfortunately, the start-stop technology is installed on less than 5% of new vehicles here in the U.S.

That should change.

President Obama’s new fuel economy rules give auto makers in the U.S. credit for this off-cycle fuel savings, so eliminating consumption by shutting down a car at a red light could hand a 4-5% boost to automakers under the Corporate Average Fuel Economy Scoring system. All improvements in fuel economy are important under the system, and experts predict that 50% of all new vehicles in the U.S. will have this technology by 2016.

Chevy’s Malibu Eco has the technology right now, and Mercedes is planning on offering 19 models with it in 2013.  Read More