optimal SOC for ending a drive.

I prefer to end with the same SoC with which the next drive begins.

 

I would think the best bet would be to leave enough charge so that the first leg of your morning commute would be in electric mode only. In my new commute I have to drive through 3 miles of residential housing so by keeping the engine off as long as possible before I have to hit the highway seems like the best bet. Since the ICE will be on 100% of the time while on the highway they battery will end up charged and the engine can then warm up.

I get horrible milage though so take what I saw with a grain of salt. lol

 

At least enough to start the ICE.

 

<div class='quotetop'>QUOTE(F8L @ Oct 21 2007, 11:26 PM) [snapback]528672[/snapback]</div>

My model is a little different:

1. warm-up - ICE must run but it is inefficient. But an ICE at low power warms up at the same rate as an ICE at higher power and less efficiency due to warm-up mode.
2. cruise - maintain efficient speeds and let the battery charge as part of this operation.
3. cool-down - use the fully charged battery to run the car in maximum efficiency, warmed up EV mode.

GOOD LUCK!

Bob Wilson

 

@Fatal,

I asked if it was best to warm up before or after getting on the highway. The concensus was it was better to warm up before, as it's better to be going at low speed at lousy mpg than high speed.


To the original topic, I've been trying to run EV on my last half mile on my commute home, and EV pulling into the parking lot area at work (really pointless, sine it's at the bottom of a hill). I've noticed maybe a 2 mpg increase in my FE. But I've only been at this for a month or so, so I'm not the most experienced at this.

 

<div class='quotetop'>QUOTE(psikot @ Oct 19 2007, 07:27 PM) [snapback]528008[/snapback]</div>

I usually park it at 4:30 pm either fully charged or 1 bar down. When I leave next morning at 7:00 am, soc drops pretty fast. This morning I had full bars backing out of the garage, it dropped down to 2 or 3 bars before I had gone a mile mostly downhill. I don't think it has ever gone purple during warmup. This is pretty consistent from morning to morning. It was 32 degrees this morning, the coldest I think my poor Prius has ever been exposed to. Because of initial soc drop, I try to have a high soc when I get home but that's not always possible. And yes, I have an ebh that is working (thanks FireEngineer!)

 

<div class='quotetop'>QUOTE(Mormegil @ Oct 22 2007, 08:46 AM) [snapback]528847[/snapback]</div>

Thank you and thanks to Bob for clearing that up. I'm going to swap my aftermarket wheels for my stock wheels and play around with driving efficiently and see how much I'm losing due to my wheels vs my driving.

 

Evan, feel free to correct me but would a high state of charge over night be at the expense of poorer efficiency for the last leg of the journey which may otherwise have been driven on electric power rather than the ICE?
So what you gain in the morning you already lost last night?

I wouldn't bother with the EV switch, if you drive carfully you can get higher speeds and further on electric than the EV switch allows before it kicks out. I think EV is best for moving the car a short distance or quietly getting out the driveway at sparrows.

 

i think it depends. in my previous location, i live on a side of a hill, so 90% of my trips was a steep downhill for the first 4 blocks. so i wanted SOC low, because i coasted in drive while warming up so my charge levels usually went up anyway.

but for the most part, i believe that trying to manipulate the charges is not recommended simply because its not enough charge to make a huge difference. without gravity to assist, the charge comes from the same place

 

Well, I'm going to try a week without EV mode at the end of my trip and then a week using EV mode.

I'll probably repeat this to make sure, and try to get a sense of which yields better overall FE.

I too live on a hill, so I tend to get a lot of charging done in the morning. If I start with all green, I tend to not have anywhere to go, and may very well "waste" charge.

When using EV for the last small stretch of my commute, I typically end with 4 or 5 bars. I can't really go EV longer, as I'm on the freeway until then.

 

<div class='quotetop'>QUOTE(F8L @ Oct 22 2007, 12:26 AM) [snapback]528672[/snapback]</div>

I'm still learning but I unless I'm wrong I think the first thing the ICE does is try to warm itself up when you first start up in the morning to achieve better emissions thereby its almost impossible without an EV switch to go electric anywhere first thing. Charge has nothing to do with it. I live in South Florida and its still not content with whats in the thermos in the am even sitting in a stifling hot garage all night.....it wants to start even with green hybrid batt. It won't even let me back out of the garage in the am on a hot night/hot morning without starting the ICE. Which is why I have an EBH on order....unless I'm wrong. Thank you.