Does ECO mode really effect?

not really. it's a throttle pedal modifier. so if your driving at one speed, it doesn't do much. more for back roads. it does, however, suppress the heat and a/c, which saves some fuel.

 

nope, same thing. it's called throttle mapping. because the car is drive by wire, the pedal is electronic, allowing the computer to determine how far you have to press it to achieve more acceleration.
in all 3 modes, full pedal does the same thing.
btw, after trying all 3, some people claim they do better in normal or power, because the pedal is more sensitive, and easier to feather.

 

Exactly. I used ECO for the first 6 months, got tired of the pedal travel, switched to normal (neither button).

 

For most of.us "normal driving" is 60. Montana is an exception.

Aside from A/C, the modes are user interface, different users will like different modes. I use cruise control 95% of the time so no mode matters.

 

Yup, EV is limited to 25 mph. It is for low speeds only, under certain limited conditions. Remember, this is still a fossil-fuel car, not a true electric car.

Even with warm weather and summer fuel, that Prius simply isn't capable of 50 MPG at your high speeds of 80 MPH. For much of the country, that speed is not 'normal'. To get 50 MPG, you/she must slow down significantly:
Updated MPG vs MPH chart | PriusChat

 

No, it just uses the same fuel as the same acceleration in the other modes, though such is achieved with lighter pedal touches.

It is not good or bad. It really has no impact on the car. It mostly just modifies the 'touch and feel' of the user interface, at the gas pedal. It doesn't actually change anything in the propulsion system.

Minor effects might be seen from different auto-shutoff behavior during warmup in stop-and-go conditions off the highway, and from the climate control system. On the highway, these differences should pretty well vanish.

If the driver had perfect reflexes, zero reaction time, infinite patience, and perfect fine motor control of the foot, these modes would make absolutely no performance or MPG difference. But normal humans are not perfect. With common human foibles and limitations, a plurality will do better in ECO, while smaller numbers will do better in Normal or PWR. And while not actually perfect drivers, some will still get the very same results in each mode.

 

Maybe fugedabout stretching tanks, focus more on mpg? There's really no rewards with the former.

 

Very crudely, it can go one mile, but slowly. But the 'it depends' factor is quite large.

The ruined batteries were in prior generations, not the 2010+.

For what really happens when the battery runs out, read the first post of this long thread:
[WARNING] Running out of gas (Gen III) | PriusChat

 

Under the same conditions, the 2010 will usually go a little bit farther than a 2005. Were you driving the 2005 slower than 80?

 

2010 has a bigger gas tank? maybe you drove the '05 in the summer, that would definitely help.
douglas tyres, hmmm...

 

Force = mass times the square of velocity. So wind resistance goes up exponentially with speed. There is a lot more wind resistance differential in going from 60 to 80 than in going from 40 to 60. MPG really starts to drop above 60 mph and the rate of drop increases a lot faster than the speed increases. That, and cars get worse mileage in Montana winters than in Florida "winters." If you get 40 mpg at 80 mph, I'd say you're doing great. You're getting well over twice the mpg of most conventional cars at that speed.

 

As a passenger, stick an arm out the window at 60 and then at 80. your car is pushing a lot of air.

 

Force = mass times acceleration.
Energy = mass times the square of velocity.

Polynomially, not exponentially. Usually expressed as the square of speed.

 

Right. I guess I'm getting old and forgetting my physics formulas. Should have made sure instead of trusting ancient gray cells. Or I should have kept it simple and just said it increases with the square of the speed. Just the way the length of a meeting increases with the square of the number of people attending it.