Different Driving Techniques on Civic Hybrid

[GasSavers_James]

Different Driving Techniques Tested on Richmond Loop

Introduction

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.

Test Conditions:

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

Description of Car:

Model Year: 2006 Make: Honda Model: Civic Hybrid
Transmission: CVT
EPA fuel economy rating: 49 City/ 52 Highway

Description of the Different Driving Techniques:

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

Efficient Technique
With Quick Accel. 62.0 63.2 -- 62.6

Efficient Technique
with Slow Accel. 63.5 67.6 65.7 65.6

Even Stephen
61.7 59.9 -- 60.8

Control 55.0 55.8 -- 55.4