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.
The next step for the start-stop technology is extending it to work when you’re cruising on the highway, by magically shutting down the engine and disconnecting it from the drive train. Volkswagen’s new hybrid Jetta will have similar technology (called extended start-stop) next year.
The combination of engine shut-downs while stopped at lights and cruising can yield as much as 12% in fuel savings. Which is, in statistical speak, significant.
Over in Europe, the start-stop technology (not including cruising engine shut-downs) is installed on fifty percent of all new cars already. Is it because the Europeans are that much more environmentally conscious than us? Or is it because of something else?
Here in the States, most of us are used to automatic transmissions, which allows for a near-instantaneous launch and acceleration when hitting the gas. Europeans like to primarily drive stick-shifts (it’s way more fun!). The difference between the start and stop with manual transmissions is between 500 and 700 milliseconds; with automatics it’s between 200 and 300 milliseconds.
And you know how us Americans are…we need things…NOW. This impatience (and just a smidge of laziness) helps to explain the difference in manufacturers adopting the technology.
But that won’t outweigh the large hand of U.S. government regulations with auto companies. Start-stop technology and an extra 300-400 milliseconds are right around the corner.