Different Driving Techniques Tested on Richmond Loop
After hearing about the Pulse and glide technique, and the four guys in the Toyota Prius who got over 100 MPG for more than 1000 miles, I wanted to test the technique with another hybrid, the 2006 Honda Civic. Although the results were an improvement over both the control test and the EPA rating for both city and highway, they were nowhere near the levels of the four men in the Prius. Perhaps on less hilly roads, greater gains could be achieved.
Also tested was a driving technique that maximized coasting and minimized unnecessary charging of the battery pack. When the throttle is lifted in this vehicle, the fuel is cut off and the valves are opened to reduce engine drag, to maximize coasting momentum. However, it is necessary to lightly touch the throttle to eliminate charging of the battery by the electric motor. While driving with this technique, charging and draining the battery pack is only done when necessary. This means charging a little bit when approaching a stop, and draining (assist) when accelerating. This yielded consistently higher efficiency than both the control test and the EPA rating for both the city and the highway.
This technique was tested both with quick acceleration and slow acceleration. Some sources claim that wide open throttle acceleration yields higher MPG with hybrids, but it was my experience in this test that the opposite was true.
For control testing, I tried two different techniques. First, I tried a technique called “Even Stephen”. This consisted of moderate acceleration followed by an even and light foot on the gas, keeping the speed moderate (right near the speed limit like all of the tests), and the RPMs moderate. This test does not make use of the fuel cut off much in coasting, as a light throttle foot is always using a little bit of gas to keep the car moving.
For the second control technique, I simulated an average driver. I accelerated moderately, drove the speed limit, changed speed frequently, did not maximize coasting, and did not slow down long before stops.
Temperature: 53 degrees F Wind: 6 MPH, variable directions
Elevation: 1,100 ft. Humidity: 85%
Description of Test Loop:
Length: 6.8 mi. Surface: smooth asphalt with some rough areas.
Terrain: hilly Speed Limit: 45 MPH, Speed Traveled: 42-48 MPH
Total # of stops: 2
1. Pulse and Glide: accelerate moderately to 3 MPH above the speed limit (48 MPH) and then coast down to 35 MPH. Then, accelerate moderately back up to 48 MPH. Repeat. Long coasting up to stops.
2. Efficient Techniques with Slow Acceleration: Slow acceleration followed by long distances coasting with a light foot on the throttle to keep the vehicle from charging. Losing a little speed on the uphill, and gaining a bit on the downhill. Long coasting up to stops.
3. Efficient Techniques with Quick Acceleration: Quick acceleration followed by long distances coasting with a light foot on the throttle to keep the vehicle from charging. Losing a little speed on the uphill and gaining a bit on the downhill. Long coasting up to stops.
4. Even Stephen: Light acceleration and a light foot kept on as much as necessary to keep up speed. The RPM s are kept low with little fluctuation. Less coasting up to stops than the two tests with the “efficient techniques”.
5. Control: Regular driver simulation, with moderate acceleration, on and off the gas frequently, close to the speed limit, and no long coasting up to stops.
Results (Miles Per Gallon as indicated by trip MPG on dashboard)
Technique Trial #1 Trial #2 Trial #3 Average
Pulse and Glide 65.7 63.4 -- 64.6
With Quick Accel. 62.0 63.2 -- 62.6
with Slow Accel. 63.5 67.6 65.7 65.6
After hearing about the Pulse and glide technique, and the four guys in the Toyota Prius who got over 100 MPG for more than 1000 miles, I wanted to test the technique with another hybrid, the 2006 Honda Civic.
What? 100 MPG in a Prius? Who were those guys!
Pulse and Glide would be much more effective in a Prius because unlike the HCH, the engine actually stops and the car glides with very little drag from the driveline. In the Civic even though the valves are open, you are still spinning the engine and transmission.
The HCHII is a wonderful car, very stylish. I would like to get to drive it one day. Personally I would prefer the HCHI or Insight however because they have lean burn and as such, IMHO, better hypermiling potential.
You should be able to locate the article on those guys who got 100mpg in the prius, by searching for "pulse and glide, and prius" on the web. I have never driven the newer prius, but would like to give it a try.
I agree that the insight has a much greater hypermiling potential...the aerodynamics, small engine, and lightness are amazing. I found it was fairly easy to get in the upper 70s (MPG) with the Insight CVT. The HCH II seems to be limited to about 65...but the engine is just breaking in. My dream car is the civic VX, but right now am driving an 89 Camry...it is efficient but not much hypermiling potential. the HCHII is my father's car.