Am I understanding this correct?

Not quite:

Drive ok

EV mode mostly to move around the parking lot or driveway. In certain conditions you can drive EV up to 25 mph, but remember, that energy comes from gasoline, so you can over do the EV.

B mode is only to waste energy coming down a mountain when your battery will be full at the bottom. It saves your friction brakes compared to Drive, but reduces regen by spinning the engine to use the friction to slow the car. In normal down hills and decelerations, use Drive and your brake pedal to maximize regen.

Eco mode and normal mode (and Power mode on the liftbacks) each offer the same power, but map the pedal response differently for a different feel. Eco makes you push the throttle further for the same response. Eco also moderates climate control in certain conditions to reduce energy loss, such as at idle.

 

I agree that the "B" is confusing. But, since the car has a CVT it doesn't really have a low gear like a normal transmission. I assume there is some type of limiter on the conical gears that prevents the belts from moving along so your engine has more torque (like a downshift). In other words, it allows the engine to rev higher without moving faster, thus the engine breaking. I've owned a lot of cars, and I can't say I have ever put any of them in "L" other than by mistake.

 

I can drive in EV mode up to 39mph.

 

B mode isn't needed on the mountains I've encountered in VA or PA, all probably under 3000 feet. You are probably using it on Mt. Washington or Pike's Peak.

 

Note that the cvt gears on the prii are not conical and there are no belts in it (or for that matter anywhere in this engine, except the timing chain). This is a "power split" design as opposed to the conical-belt style cvt that Honda and some others use.

 

The Prius PSD design is an eCVT. There are no belts etc. All "torque conversion" and controlling the speed of the ICE whether for acceleration or engine braking is done via the two motor/generators. There are many good threads on this in Priuschat, but my favourite site for understanding how the PSD accomplishes this is:

Toyota Prius - Power Split Device

 

I didn't realize that. Very good website. Thanks.

 

PSD is true gear genius!

 

Interesting...what are your settings, just regular old EV mode?

 

No "belts" in the Prius. B turns the ICE into a air pump. The gas engine is made to do work by pumping air through it.

 

Yes, I just used regular EV mode. I never press the EV button to engage the EV mode, I engage it by keeping it under the Eco/EV line on the small LCD display.

I drive about 45% EV and 55% gas and electric mode for the rest.

 

I can maintain "ev" as well up to 45 mph the same way if the ground is completely flat or a slight downhill

 

Well stated!

 

Awesome! So do you have it in ECO mode and you just go light on the gas to keep it under the line in the display, or is ECO mode off?

 

I keep Eco mode on all the time and from a stop, I press the gas pedal for about 2 seconds to accelerate slowly in electric mode, then I accelerate more and stay in the ECO range of the bar in the LCD dashboard display. I accelerate to just over the speed limit and then let go of the gas and reapply to engage EV mode and gradually slow to under the speed limit. I then accelerate with the gas engine and repeat.

Also, when I am almost home, I use EV mode completely for about .6 miles on a 35mph road and then about .3 miles on a 20 mpg road to my house. This really brings up my mpg.

 

I guess I've been doing the same thing without even knowing I was doing it. Since I got the car on wednesday, I've just kept it in ECO mode and I've tried to stay around 35-50 mph, usually going as many back roads as I can so I can go slow. I've been getting insane MPG.

 

Unless you have a good downhill slope to recharge the battery with brake regen after using EV, it's the ICE that will have to work harder and burn more gas to do that. Remember, the electricity comes from the gasoline in a non plugin hybrid! It's long been considered the most fuel efficient method to keep the battery as full as possible, reducing the ICE workload. But learn the terrain, take advantage of EV when you know you can get a "free" recharge going down the next hill!

 

EV driving produces a false sense of economy. You get great mileage while doing it, but you have to pay it back with interest to recharge the battery.

It's like living high off your credit card: Everything is free for a month, and then you have to start paying it back, with interest.

Use EV wisely to avoid unnecessary use of the ICE, but don't expect EV driving to save gas in normal use.

Tom

 

Also look and learn on the otherhand...

When the ICE is running, take advantage and use the engine power to take to the top of the eco line.
If the ICE is running, it is running, so use a bit to get up to speed, or gain some MPH to coast later.