GreenHybrid - Hybrid Cars - View Single Post

sdctcher · #5 (**permalink**) 01-30-2005, 12:04 PM

OK. Thanks Wayne. Let me pass something by you (and any others that want to post) and maybe it might become fodder for a new thread at some point:

I am trying to edit a short driving tutorial for the Escape Hybrid using advice passed on by all hybrid drivers. I am not sure as yet whether everything applies totally to the FEH but it is worth the experimentation. The goal here is the best possible mileage efficiency since we have no way to monitor whether these strategies are best for the environment and emissions. I would like input from experience and theory. I will then take the input and put it into practice. I am already getting pretty high numbers despite having 4WD, living at high hilly altitude, and cool temperatures.

FEH Driving Guide

Garaging:
Try to garage your car from cool temperatures. Time required to get up to maximum efficiency may decrease becasue of the amount of heat needed to get the batteries and exhaust elements up to best operating temperature.

Vehicle Weight:
This is not a critical issue. At a FEH Curb Weight (excluding gasoline) of about 3150 lbs. the weight of a full tank (94-98 lbs.) of gas is only 3% so carrying 1/2 tank will save only 1% of weight. Passenger and Cargo weight is more important (125 - 500 lbs. or 4 - 15%) so leave at home anything or anyone you do not need to haul around.

Fuel Type:
Buy the cheapest gasoline that meets minimum octane standards. Higher octane will not increase efficiency measurably. Ethenol blends (corn-based or alcohol additives) required in some areas will decrease efficiency and you may have to buy the next highest grade to get better mileage (from my experiences).

Use of Accessories:
Limit the use of accessories, especially those that are indicated by red settings. Anything drawing power requires that power be generated by ICE. Drive with as clean a profile as possible, including windows up and no flags or other appendages flapping in the wind.

Start-Up:
After start-up get the car moving as soon as possible and let the warm up be on the road.

First Few Minutes:
The EV will not kick in for at least 3-5 minutes after a cold start so do not even think about it. Accelerate the ICE up to your target speed gently keeping the RPMs in a range from 1500-2500. (We need a curve to find the sweet spot when the engine is cold). If the engine is warm from a previous drive use the electric as aggressively as possible to accelerate to where the ICE kicks in.

Low Speeds:
The EV is best for gas mileage to boost quicker acceleration, coasting downhill if not charging, and while stopped. Try to use just the ICE at low RPMs as much as possible. Do not try to set a record for staying in EV because minute in EV without ICE means at least a minute later of the ICE working harder to recharge the batteries. At 20-30 miles per hour over an extended distance with few stops I have maintained over 50 MPG by using quick acceleration to ICE, then a light foot to maintain desired speed. Try it in a deserted shopping center parking lot as an experiment.

Stop and Go:
Start aggressively on EV and then keep ICE RPMs low and coast as much as possible. Use the brakes as much as possible, even heavily, because this gives a higher and faster charge than coasting. Time the lights and other obstructions to try to maintain forward movement. Energy to restart movement from a dead stop kills mileage whether in ICE or EV.

High Speeds:
You should get your best mileage with the RPMs as low as possible. 1000 - 1500 is great but for cruising on level road try to stay 1500 -2500. I maintain that Hybrid Drive (drawing on both Engine and Motor for drive) is most efficient if the battery level is receiving a dump of excess energy off and on during the process. Try not to get into a position where heavy acceleration is needed, like getting on the freeway or passing. Try to gauge conditions ahead and accelerate smoothly at lower RPMs.

Uneven Terrain:
On extreme upgrades you may have to boost RPMs to the 4000 - 5000 range to maintain desired speed but do it as little as possible. Anticipate the crests of hills and coast up near the top bleeding off some speed before the coast down. Use heavy-foot braking going down while maintaining desired speed. Most of all, do not use automatic speed controls or try to stay in a narrow range. Set a speed range in your head of 10-15 miles per hour with the bottom range the minimum speed legally allowable for this road. Most of the time people will pass but at other times you may have to sacrifice your efficiency for their impatience. Remember. You are buying your gas, not them. On longer downhills use your excess momentum to reach the highest possible speed to coast up the next grade. If there is a choice of routes (short, steep upgrade vs. longer, less steep upgrade) take the road less travelled for best mileage. This also applies to freeway vs. surface street routes if time is not a critical factor.