MPG and Power: Driving alone vs. driving packed

I never try to use electric only, as I prefer good gas mileage. It always costs you extra to regenerate electricity from gasoline.

 

I realize this is debate, but the optimum driving style is different between the C and the lift back. Limited ICE power and battery capacity changes everything. We drive our Ford C Max differently than the Prius C. The C Max runs at least 40% of the time on battery only. Li-ion batteries make a difference I guess.

Anyway, additional weight really taxes the Prius C, with its limited resources.

Not being negative towards the car, but its happier with the driver only, and city driving. Just what it was designed for!

 

Extra weight has the largest effect when accelerating (from a stop).
So it would have the largest impact in stop and go situations.
It should have little impact when "cruising" at a reasonable speed.

Now......the extra weight would, theoretically, also result in slightly more energy recovered during regen braking but there still would be a net loss for the extra weight.

Making sure your tires are at or slightly above the recommended pressure is important with the extra weight too.

 

Your MPGs may go down from having a full load, but your efficiency is really going up. Just you in the car at 50MPG gets you 50MPG per person. You plus 3 friends at 47MPG gets you 188MPG per person. (Actual MPGs may vary, of course) That's why carpooling is so great, an average car with 2 people or a truck/SUV with 3 or 4 people is just as efficient per person as a Prius with one person.

 

We,ve never measured acceleration and mog on 'packed' vs single driver but you should expect a substantial drop in acceleration because the weight tncreased amost 20%. since you weigh 220 lb try carrying a 435 lb back sack and you get te idea.

 

I carpool (with two others) two to three days a week and I notice about a 5 mpg difference with passengers.

 

Have use d my Prius C Two to goto a local Wal-Mart that is about 25 miles from me. By myself I get about 52 mpg. When I go with my wife and sister-in-law we get around 66.

 

Well it is misleading information.
Unless the two passengers are elephants, that much difference is highly unlikely.
Extra weight makes a significant difference ONLY during acceleration.......and the hybrid design tends to minimize that.

Maybe the driver pays less attention to efficient driving techniques when other people are in the car.

 

This can be true, IF you define turning as accelerating sideways and braking as accelerating backwards, otherwise it is false.

Any time there is a change in momentum, weight costs MPG.

 

I've really not noticed much difference in both mpg/power, driving alone in a 110 mile highway stretch or driving with wife+kid+weekend stuff

 

OK your first one was pretty good but then........you had to get serious.

When one has regen braking, the decel actually gains back more with higher weight.
Not enough to offset the additional energy required to get going again though.

 

acceleration and decleratio regardless of being from a stop are reductions in mpg.

sure its not from a change in car level; dropping the back end could easily make the fuel level show higer mpg.
Or it could be better aero. Or a combo.

 

Deceleration itself does NOT result in increased fuel usage.
It just does not.

The resulting acceleration back up to speed certainly does though.

 

If you are able to get 66 mpg, then those 25 miles must be mostly at speeds between 25 and 55 mph. I would expect mileage to go down, at least a little, with more weight in the car, even if it's only a couple hundred pounds. So I suspect it's a change in your driving that's caused you to get higher mileage with 2 more people on board.

I think many of us tend to drive a bit less erratic with passengers than we might when alone. Especially relatives
It's easy to push the car just a bit harder and think nothing of it when you have a hand or two on the steering wheel to steady you. But passengers don't get that kind of advantage. There's a fine line between the kind of forces present going around a curve in the road that will cause your passengers to lean almost uncomfortably this way or that, but have no effect on the driver because of his hands on the wheel. I suspect that, maybe even subconsciously, you are driving a little smoother and gentler with them in the car, causing an increase in gas mileage. Make any sense?

 

It does. (sometimes) If you are braking from a given speed, more weight makes it more likely that you will exceed the limit for regenerative braking and require actual brakes, resulting in a increase in fuel usage.

 

I'm not sure, but I think Easy Rider just called Shibby's passengers "elephants"!

 

It doesn't necessarily make any sense to get better milage with 2 more people on board than when I make the trip myself - yet both times the wife/sister in law have had fun watching the mpg gauge continue to rise from when we leave her apartment. Its quite the joke that we need her in the back seat to get better mpg so thats why we pick her up The trip is mostly 35-50 and has an equal amt of up and down hills going both ways so no real advantages there.