EV button

The Manual describes it well.

But - in most situations it's best to ignore it ... and let the computers in your PRIUS sort out when it is best to use EV. The most likely time I use it is if I want to come silently into my driveway - so my dogs then don't start getting excited till they hear me shut the car door. Overthinking of the EV Button might mean that you actually end up with worse l/100km than just letting it do it itself.

The EV button won't work at all if you've got the heater on, which you're likely to use in Canada - it needs to run the Internal Combustion Engine (ICE) to provide heat. Nor will EV work if you've got 3 bars of Hybrid battery or less. On cooler days, if you really want to use the EV button when you start up, you need to hit the Climate Control OFF button the moment after you press start (or before you park) - or it'll start the ICE and there's no turning it off till it's warmed up.

EV will, if you're careful to not use much accelerator, hold off the running of the ICE - if the ICE is cold, will allow you go get to 38km/hr then fire the ICE. If the ICE has warmed up, then it will go faster than 38, but depends on accelerator (and how steep the road is).

But, it will use the Hybrid Battery charge up quite quickly (unless you're going downhill) - and if you don't think it through carefully, you might find that you've got low charge and it would be advantageous to run in EV mode automatically at a point where it may have been possible to hyper-mile but can't because the ICE needs to charge up the battery again.

You might find some places where it is useful. I've got a 2km stretch, very slightly downhill just before I go onto the Motorway. The Motorway NEEDS the ICE for acceleration and the slight incline for the first couple of kms, so if my battery is pretty-well discharged at that point, I've possibly saved some fuel. Maybe.

Have you read Tony Sheafer's article on HYPERMILING - it sort of touches on use of EV mode, but I don't think he bothers with the EV button:

Tony Schaefer on Hypermiling » What Drives Us

The best way to work out if you're in EV mode is to watch this screen:



IGNORE THIS screen - it is probably the one your salesman left on - it's prettier, better entertainment for passengers, but the important part is duplicated in the HUD. If you do use it - the EV indication is very very approximate - I would ignore that screen altogether - put up the previous screen I put up instead

 

Normally the car figures out best when to use the electric motors. Above 50% acceleration (the middle line on the acceleration guide) the ICE (Internal Combustion Engine) will always active and it will use both ICE and EV, or just ICE.

However, if you press the EV button, the car may go into electric only mode for a short time. During this time, you can press the accelerator quite a bit past the middle line on the acceleration gauge and the ICE is less likely to activate. Accelerating too hard, or going faster than around 25MPH, or the battery getting to about 3 bars, and EV Mode will deactivate and you'll go back to the normal mode where it uses both ICE and EV as and when it sees fit.

When would you use it? If you want to drive around quietly, such as in a parking lot, when leaving/coming home at unsociable hours, if you're hunting and want to sneak up on that big game (not serious), etc.

I say "may" go into EV mode above, because a lot of things have to be satisfied for it to do this, such as temperature, cabin temperature, battery level, engine temperature, and so on... Alanclarkeau has detailed this very well above.

 

From what I gather, whenever you push this button, it Beeps and says EV Mode Not Available...in other words, it's useless.

 

I hear your there!

Pixel 2 ?

 

It sometimes seems that way - in reality - that's less likely than really happens. BUT - it seems to happen often on the few occasions where I think it could be beneficial to go to EV mode.

 

I'm sure it's similar to my GIII, and with Pearl S I use it to move the car in/out of the garage or into the back yard to wash it, in summer only of course (won't work when it's cool out). Handy to surprise the neighbors. Told them the car was about to "hover" with the noisemaker sound as I backed it out of the back yard. I think they believed me for a few minutes!

 

If you do a cold start you can -sometimes- force the car to not do the "cat warmup cycle" when you are just moving the car a short distance. That's about it for me. So in those cases you avoid the potential of the rough startup next time.

 

But that's exactly it, you can push the accelerator (almost?) up to the PWR area of the acceleration graph in EV Mode without the ICE kicking in. Acceleration is considerably brisker, despite it still being electric only, compared to the maximum you can get from just being able to use up to the center line on the acceleration bar. You can also get up greater inclines. If you truly want just electric only for a short time, EV Mode is potentially much more forgiving and useable in the real world.

That being said, the 25mph limit is somewhat frustrating.



SM-T813 ?

 

Thats exactly what I do in the winter when I want to get the car out of the garage to wash it and then put it away without having the ICE start up.

 

In a previous commute to work, I would have a downhill coasting offramp exit from the freeway. By the time I reached the signal at the end of my offramp my battery was maxxed out. I would push the EV button and I would drive the 3/4 of a mile to my parking place. Did this every day. I'm sure it led to better numbers on my 2008 Prius - but now that that opportunity no longer exists I don't use it much anymore...