Moderate uphill driving in Eco or D mode?

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oahumiev

Well-known member
Joined
Jan 26, 2012
Messages
57
Location
Oahu, Hawaii
Is it better to drive on a moderate uphill in Eco or D mode in terms of least battery consumption? Curious to know if driving in D would be more efficient since in Eco mode, the meter is in the power zone on the right and wondering if the Miev is actually having to work harder due to being in Eco mode? On a very steep grade, I'd obviously use D to ensure I'd make it up the hill.
 
I don't think there is any difference. That is, if you go up the hill at the same speed, it will use exactly the same amount of battery power whether you are in D, ECO, or B. I think all the ECO mode does is make you push harder on the "gas" pedal to get the same amount of power. I think this is to discourage you from accelerating as hard.

Some ICE cars also have an ECO mode. Here there can be a real (but probably small) difference in economy. The car can use higher gears which generally gives better economy with a gas engine, but it makes the car more sluggish if you suddenly step on the gas. Our cars don't shift gears, so this doesn't apply.

Say you want to go up a given hill at a constant 35 mph. Now regardless of where you put the shift lever, the motor will spin at the same speed, and it will have to put out the same torque. The motor doesn't have to do more or less work depending on where you put the shifter. Unlike an ICE car with gears to shift, our car can respond nearly instantly to any changes in power required. Our car won't be any more ready to accelerate or decelerate by running a tad less efficiently at any given time. Thus, there is no reason for Mitsubishi to program the car to run less efficiently in D than in ECO (for the given power level being asked for by the driver).

In short, to go up some hill at a constant 35 mph will require the same 25 hp regardless of whether you have the shifter in D or ECO. Why would Mitsubishi program the motor to run less efficiently in one mode than the other? Unless there is some advantage, they aren't going to say "Oh, when it's in drive, lets purposely program it to use more power than it needs to". The ECO position is an attempt to modify the drivers behavior to ask for less power which can improve efficiency.

PS - Of course the ECO mode also applies a higher level of regenerative braking, which can help with overall efficiency, but the question was about going up hill so I ignored this function.
 
JoeS said:
Uh, how's this work.... +2?
In other words, I second that motion!
Economy mode only changes the 'pedal authority', and simply substitutes for precise foot control. ;)
-Jay (who, apparent from usual driving range, has a spastic right foot)
 
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