Just got a Prius about a month ago

In order to USE energy, it must be first PRESENT!!! ie: A Charged Battery!!!

 

[ame=http://en.wikipedia.org/wiki/Potential_energy]Potential energy - Wikipedia, the free encyclopedia[/ame]
[ame=http://en.wikipedia.org/wiki/Kinetic_energy]Kinetic energy - Wikipedia, the free encyclopedia[/ame]

Perhaps the rest of this conversation should take place after you are clear on what is meant by energy.

 

I'll try to explain again.

1) All the charge stored in the battery ultimately comes from the gas tank, whether through direct charging or indirectly through conversion to kinetic energy and then recovery from regenerative braking.

2) Regenerative braking is a lossy process: you do not capture all the kinetic energy you had as charge and the process of retrieving the charge and converting to kinetic energy is also lossy.

3) If you use the brakes you are decelerating more rapidly than you would do while gliding (engine off, electric motor off), therefore given the same starting speed you travel much further in a glide than you do while braking (either with your foot off the gas pedal or on the brake). The heavier the braking the shorter the distance you travel before you reach your target speed.

Therefore:
- the less decelerating force you use the earlier you can begin deceleration
- the earlier you begin deceleration the earlier the engine and/or electric motors can be turned off
- forced deceleration trades increases the time with the engine/motors running before deceleration while adding regenerative charging during deceleration
- the energy used during those two time periods is
(additional engine and/or motor energy) - (regenerative energy recovered)
- since the regenerative braking process is lossy the additional energy consumed will be greater than 0

Forced regenerative braking is worse than gliding.

 

It's Not About The Money: I believe you are totally correct. When I come down from my local Mountain range and my Prius shows 55 to 70 mpg, it must be all in my imagination. I will be sending off a letter to Toyota Motors explaining to them why their entire concept is false. You don't mind if I quote your theories? I never said anything about forced regenerative braking ???

 

Again, you've missed the point.

The presence of regenerative braking doesn't change the fact that coasting is braking and it is less efficient to coast than to glide and then, if necessary, brake using heavier regenerative braking.

Please stop advising people to coast. It is inefficient.

Feel free to write to Toyota so their engineers can explain it to you.

 

Previously:

Keeping your foot on the brake pedal (lightly) IS forced regenerative braking.

 

I agree, but only on downhill modes with no loss of speed. AND, only done when a charge seems to be required. If the Bat is in the green (totally) I don't worry about it and let the cruise control take over. :cheer2:

 

To continue this silly conversation, I suggest options and people may take them IF they wish. Point in fact: Today, traveling northwards, in this part of the country that means slightly uphill, My MPG went from 45.1 to 45.9, in a suburban environment, for about 10 miles. Caught 3 lights and timed the rest. On any available downhill portion I rode in neutral and then regenerated approaching traffic lights WITH my foot lightly on the brake pedal for maximum regeneration. I only sped up once to 55 to get ahead of a vehicle so I could make a left turn. SO PLEASE, the end to this energy conversion crap, it does not apply to the Prius. It is all in your head. :welcome:

 

I recommend that the OP ignore all the postings on how to eek an extra .01 mpg from the tank and enjoy her ride. However she drives her Prius I'm sure she'll get better MPGS than her old car.