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The dealer says up to 1 mile at no more than 28 MPH for EV mode...I have heard if you go about 60 MPH and let off the gas, it will automatically defer to the EV mode unless you gas it up hard under heavy acceleration. However, using it the way it's intended...you are in traffic or coasting to a red light..you push the EV button...and, once you start moving in stop and go traffic, can you go more than the mile suggested if you are repeatedly stop and go in traffic? What I mean is does the braking charge the battery enough in traffic to allow you to go a few miles in EV mode only???
 

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As a Prius owner, I can help you out. Sorry for the long post...

The HV pack can sustain a certain amount of acceleration, and will disengage at a certain speed @ 28MPH / 40 KPH. I did just that in a shopping center parking lot yesterday. This is by design.

When you choose EV mode (button) it will also disengage depending on the Hybrid mode (Eco, Normal, Sport). In Sport mode, you can do greater 0-28MPH acceleration (faster) then when in Eco/Normal. Again, by design.

If you deplete the battery, it needs to be replenished, to keep all the cells healthy, and the only source is gasoline, the ICE inside the HSD spins one of the electric motors, causing electricity to be generated, that recharges the HV battery.

So depleting the battery to 15% will simply cause the ICE to start on it's own, no matter what you do, to get the battery into a safe zone (around 25%), and so on.
So 'killing' or 'juicing' the battery will NOT get you better MPG.

Unless your car can be plugged into the power grid to recharge the battery, you max EV mode getting off the highway to your house, and before the battery 'dies' you turn OFF your car and plug it in. Or have an alternate battery source (research Engineer Plug-In system) that "fills up" your HV battery when your HV battery is not solicited.
This "tricks" the HSD into NOT turning on the ICE to recharge your HV battery, because it never falls below 15%.

IOW, the CT200h or the Prius are NOT electric cars, they are hybrids. Gasoline is used when it makes sense, uses less gasoline, thus less wear & tear on the ICE, spark plugs last longer, cleaner emissions because of Atkinson cycle engine and the assist from the two electric motors.

Regenerative braking will save you $$$ in brake upkeep/repairs - the actual gas savings are probably just in the 10% range.
Must Prius owners (myself included) only have had 25% brake pad wear after four years of city driving every day.

The R. braking is all about absorbing energy, much like an 18 wheeler will downshift to save wear & tear on his brake system and to keep it from overheating.

The HSD system does it for you. Just let go of the gas. You then have some choices :
1. coast
2. slow down gently
3. slow down faster
4. stop ASAP

1) This is the famous pulse & glide, or another way to save energy. In pure EV mode you can use power "pulse" between 0-28MPH, then coast down, then pulse again.
It is also referred to being *extremely annoying* to traffic following you. In traffic you want to maintain constant speed / follow, not create gaps in front of you, then catch up, then create a gap again, etc.
BUT it is how people get crazy MPG numbers. There is some benefit in traffic. Sometimes.

How : you let go of the gas completely. Then lightly press on the gas pedal, like one pound of force, just so the car registers you are pushing on the gas.
The car is now "gliding" or coasting. No gas is being used, no electricity is being used, no regen is being had.
You could slow down to almost a stop, then pulse up again. Never stop.

When : In traffic, use coasting halfway to a red light or a stop sign. So you are slowing down due to friction of the air & wheels on the ground.

I typically start from a stop at the same speed as everyone else, and when I see I have to stop soon, I coast as long as possible. This is similar to a car with manual transmission pushing the clutch, preparing to brake, but not yet braking.

When you do have to brake, brake normally. You'll get some regen. To get crazy MPG you want to use gas, but in the "sweet spot" of less than 50 MPH, and coast down to 30 MPH, then back up to 50 MPH, non-stop. This is how a Prius driver went from Chicago to Washington DC on less than 6 gallons.

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The next numbers
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2. slow down gently
3. slow down faster
4. stop ASAP

Involves how you brake. This controls the regen you'll get. This also works with the Cruise Control - when you push down to slow down, Regen kicks in, not coasting. The only way to coast with zero energy used - think of a skateboard when not pushing it - is gently touching the gas.

2) & 3) depending on how much you press down. The Regen part, when the needle swings down on the left, shows by how much.
No need to crunch numbers - if % efficiency varies between 5% and 10%, you'll never see how much your braking varies your MPG, it's too tiny.
So don't worry about it.

4) is obviously the worst way to brake - you push fully down - and friction brakes will be used, thus momentum energy is lost. Like a conventional car.
 

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The dealer says up to 1 mile at no more than 28 MPH for EV mode...I have heard if you go about 60 MPH and let off the gas, it will automatically defer to the EV mode.
Nope, misinformation. Car will go into the 'slow' regen mode. ICE will turn off if it can.

At speeds up to 48 MPH you can 'coax' EV only by accelerating lightly, making a Grandma in a 85 Tercel pass you and giving you dirty looks.
No practical reason for this.

EV mode exists only because the customers have asked for it. When the G2 Prius came out, the NA model didn't have an EV button, but the EU/Asia did.
People wanted it - but it serves no practical function in getting great MPG.

It's more like on a Casio keyboard/synth, there's a DEMO button.

The *only* good things are the ECO mode and the SPORT mode.

In rush hour traffic & such, use ECO, and you'll get damn close to 50MPG with normal driving.

In SPORT mode the two electric motors will drain the HV faster for more HP's, which forces the ICE to kick in, regenerate the battery more often, thus lower MPG, say low 40's.

With the CT200h, I would use SPORT mode for passing on the highway quickly or getting on the highway quickly, just because I can.

The cost difference between the two driving styles, at 4$/us gal, is smaller than what most people expect.

Would you care about 10$ per month driving a Lexus? Nope.

The more frequent charge/discharge of the HV battery using SPORT vs ECO means you might want to change your 2.5k$ HV battery after 400,000 miles instead of 500,000+.

Remember that in 400,000 driven miles you might not even change your brakes, not once ! Oil changes 40% less often too.
 

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I'll tell you this: The CT will kick you out of EV mode a lot sooner than my 2005 Prius (with it's hacked EV button).

Let me give you and example of where the EV mode has a slight gas-saving advantage, albeit minor:

At the exit from my place of employment, there is a traffic light. If you drive the car normally, you will be sitting at the traffic light with the engine running as it tries to warm up. If you can coax the car along in EV mode, you can drive to the light and sit there in silence until it turns green. You are forcing the warm-up cycle to occur while you are driving instead of sitting.
 

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I'll tell you this: The CT will kick you out of EV mode a lot sooner than my 2005 Prius (with it's hacked EV button).

Let me give you and example of where the EV mode has a slight gas-saving advantage, albeit minor:

At the exit from my place of employment, there is a traffic light. If you drive the car normally, you will be sitting at the traffic light with the engine running as it tries to warm up. If you can coax the car along in EV mode, you can drive to the light and sit there in silence until it turns green. You are forcing the warm-up cycle to occur while you are driving instead of sitting.
Use the combo of SPORT mode + EV mode. This is also true with the Prius. Assuming your battery charge (SOC) is 75% or better.
You'll get to 28MPH w/o feathering the gas pedal. The 'sport' makes the EV stick around longer. Or less sensitive. Counter-intuitive?

The red light when your car is cold - that's a good trick. :)

The singular best way to save money (and great MPG) is mastering how to coast, and using the Cruise Control on the highway, following someone bigger than you if possible.

One thing to note with the cruise control. At 60-65MPH the HV battery recharges quickly, and when full, driving level, the car will oscilate between gas only and electric only. Cool to watch.

This is to bleed out the surplus energy being stored. The electric motor never operates long because at high RPM's it would overheat, which is the Achilles heel for electric motors. (true also for transformers)

Thus on pure highway runs (over 5 minutes), gas consumption is quite low. For most new hybrid owners, they get better MPG driving 20 miles on the highway than 20 miles on small roads.

No amount of foot work will not allow you to use EV above 48MPH.
 

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Discussion Starter #7
yes...thanks to all of your EV posts...I'm learning it's not just driving but rather a science to getting the best mileage
 

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I commend everyone for the explanation of how to improve gas mileage.

However my wife is never going to do all that fine tuning to get the extra fuel economy.

She will be thrilled just because she went from a car that got "maybe" 20 mpg to one that gets over 40mpg with no special effort :):):)
 
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