Aside from slowing down on the highway, the fastest way to boost your fuel economy is to master the art of “pulse and glide” driving.
Several Prius drivers I’ve spoken with, who complain of “low” gas mileage in the mid-40’s, are surprised to learn that one of the main culprits behind their failure to climb above 50 MPG on the energy screen is, counterintuitively enough, is an over-reliance on the electric motor.
As the Prius’ battery is quite weak (improvements are said to be in the works for the 2009 model year), driving on electric power (yellow arrows moving right-to-left on your consumption screen) is not an efficient way of getting around. After as little as half a mile, the battery will have been drained below 20%, causing the gas engine to turn on and charge the battery. Because of inherent (and unavoidable) inefficiencies in the machinery, the net result will be more gas consumed in charging the battery than was saved while emptying it. Thus, attempting to drive in electric mode whenever possible will actually reduce your overall mileage.
Learning how to properly pulse and glide your way to 60+ MPG will take a little patience, a relatively straight, relatively level road where you can safely maintain speeds of 35-40 MPH for long stretches (a road with a lot of stop signs and traffic lights is not ideal), and careful attention to the consumption screen.
The first step, of course, is Pulse. Accelerate up to no more than 41 MPH (the point after which the gas engine will not shut off), using moderate pressure on the accelerator pedal. You should be able to reach 40 in six or seven seconds without “gunning it” (4.9 seconds with maximum throttle according to Motor Trend - but that’s not really good for fuel efficiency).
To glide, lay off the accelerator for a split second before reapplying just enough gentle pressure to get the blue (regenerative breaking) arrows to disappear, as shown below:
If the yellow arrows come back on, lift your foot off the pedal and try again. In this mode, the gas engine is turned off, and car is neither draining the battery (yellow) nor charging it (blue). Using this technique, the car will gradually slow down due to tire friction and wind resistance; once the speed drops into the low 30’s, give it some gas to pulse it back up to 41, and repeat.
You can accomplish a reasonable facsimile of this process, by the way, in any non-hybrid car with a manual transmission - pulse up to your desired speed, shift into neutral, and turn off the ignition. Do it on the highway, though, and you’ll likely end up dead, having been rear-ended by an 18-wheeler.
After a while of consistent application, Pulse and Glide will become second-nature, and you will no longer need to look at the consumption screen to reach than zen mode of no arrows in either direction. Until you reach that comfort level, however, do try to keep an eye on the road as you drive.
[...] This blog over at WordPress gives some great first-hand advice on how to use the technique: Learning how to properly pulse and glide your way to 60+ MPG will take a little patience, a relatively straight, relatively level road where you can safely maintain speeds of 35-40 MPH for long stretches (a road with a lot of stop signs and traffic lights is not ideal), and careful attention to the consumption screen. [...]
By: Pulse and Glide | HypermilingFAQ.com on June 9, 2008
at 11:01 pm
