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I'm reading through some of the literature/manuals that came with the car. Pg. 3 of the "Hybrid Overview" pamphlet says that operating the vehicle in EV mode will not increase overall fuel economy. I'm confused. This mode uses only the electric motor powered by the hybrid battery, how does that not increase fuel economy? Is it because it draws down the hybrid battery and then necessary replenishment negatively impacts fuel economy? Or is it because the time spent in EV mode is probably such a small percentage of overall driving time that you wouldn't see any measurable impact?
 

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I'm reading through some of the literature/manuals that came with the car. Pg. 3 of the "Hybrid Overview" pamphlet says that operating the vehicle in EV mode will not increase overall fuel economy. I'm confused. This mode uses only the electric motor powered by the hybrid battery, how does that not increase fuel economy? Is it because it draws down the hybrid battery and then necessary replenishment negatively impacts fuel economy? Or is it because the time spent in EV mode is probably such a small percentage of overall driving time that you wouldn't see any measurable impact?
I think they are trying to discourage you from using EV mode too much.

Obviously, using the battery to power the vehicle will deplete the battery. That charge has to be made up somehow. If it's the gas engine recharging the battery, then EV mode won't save you much.

However, let's say you live on the top of a hill and every morning your battery gets fully charged by braking while going down the hill. You might as well use up your battery's charge before you go down the hill.
 

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^^^ yup. thats the idea. Esp your hill analogy.

Its all about energy management. Despite going down that hill......at some point you have to go up too!

Use EV mode when you KNOW you don't need high speeds and don't need acceleration. Such as crawling in traffic. Force the vehicle into EV mode when you are in traffic and when you do get moving again, make sure you're light on the throttle pedal so that the vehicle can regenerate but not use too much fuel in doing so.....ie use the momentum of the vehicle to do the recharging.
 

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As an owner of a 2005 Prius, I can tell you the most aggravating scenario is when your battery is 100% full.

At that point, none of the regen braking gets captured and if you're stopped, the electric motor will even spin the gas engine for the sole purpose of discharging some of the extra juice.
 

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Its necessary as the battery's state of charge is important in maintaining the longevity of the battery. The reason why Prius' go for 300,000km+ with no battery issues is because Toyota engineer's the batteries to reduce the state of charge swing. Too low of charge and too high of charge drastically reduces battery life.
 

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Do I unplug the battery? Where and how?
That's a nice vacation.

Ideally, you could have someone come over and run your car for a few minutes every couple of weeks. If that's impossible, I would recommend unhooking the 12V battery (not the hybrid battery). Consult your owner's manual for more information.
 

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I personally don't see the need for the EV switch...if my battery has a lot of charge, and I'm driving at about 42 MPH or less without gassing it up hard, my car lights up the EV light on the left of the energy management gauge...that means I'm driving at around 40 MPH in full electric (am I right)? So, even at the low speed, if you know how to work the gas pedal and let off so the CVT transmission keeps the needle at halfway (9 o'clock position or less) mark, you are in electric...it's great and can't imagine that doesn't get you extra MPG.
 

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Yes. When you're at ~40 MPH and the battery is charged and your needle is at the words ECO or below, it will net the best fuel consumption.
 

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I personally don't see the need for the EV switch...if my battery has a lot of charge, and I'm driving at about 42 MPH or less without gassing it up hard, my car lights up the EV light on the left of the energy management gauge...that means I'm driving at around 40 MPH in full electric (am I right)? So, even at the low speed, if you know how to work the gas pedal and let off so the CVT transmission keeps the needle at halfway (9 o'clock position or less) mark, you are in electric...it's great and can't imagine that doesn't get you extra MPG.
Yes that is correct But the EV switch is there so that if you want to force it to only use EV then you can, for instance if you are just moving the car in or out of the garage, or in a car park looking for a space and parking.

The warning about using EV and your mpg is there for those that don't fully understand the system if you do over use the EV it will force the engine to come on and charge the battery for normal driving using The Eco monitor and throttle to get in to EV will save mpg as that's is what it's meant to do !

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Yes. When you're at ~40 MPH and the battery is charged and your needle is at the words ECO or below, it will net the best fuel consumption.
I agree, that's right bondguy. I only use the EV mode button if I sometimes just need to move my car out of the garage or move it into the street for some reason....hit it immediately after starting the car to avoid the gas engine from starting.

One thing to clarify Matt - I've found the EV mode only kicks in if the grade is fairly flat or down hill. Any slight uphill grade, and my car's eco/energy needle will go above the 1/2 way mark and then the gas engine kicks on.
 

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I don't like the non-ability to drive in EV mode when I start my vehicle, it would be handy for parking lots and in the neighbourhood. Some people have said that might be due to using EV mode before parking and no battery charge but is battery charge lost if its been parked for awhile?

For example, say battery is fully charged. I park for 4 hours and its reading charged but EV mode can't be turned on. Anyone else have this issue, maybe I'm over thinking it.
 

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Did anyone else notice that when the Nav screen shows you are on battery power only ( yellow arrows only) that sometimes the car icon with EV on it doesn't come on even if the gauge shows below 9 o'clock. It's almost as if the two systems are not in sync completely. I noticed this a few times.
 

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I'm also well aware that the car does sometimes go into EV mode automatically..
 
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