EV - Is it really helping me?

There are a few situations that I think it's clearly helpful.
1) Slow moving traffic, particularly waiting your turn to go through a light or stop-sign. IOW, if you're just going to creep forward 50-100 ft when the light turns green but it will turn red again before you get to it I would use EV here. If you hit the accelerator a little to hard the ICE will spin up and run (burn fuel) for a while for no good reason.

2) If you are going less than 35mph as you approach a stop and the ICE is still running. You can force it off as you glide to the stop point where it otherwise would continue to run even as you slow and for a few seconds after you stop.

3)If you're just briefly starting the car to move it around the parking lot or something.

4) It might be a good use if you know you'll have a very long wait until you get on the road. For instance if I'm leaving a local minor league ball game with the crowd and I'll have to be in the parking garage for 15 minutes waiting to get to the road I usually use the EV mode until my turn to pull out onto the main roadway. If I don't the ICE will start, run for a while, shut down...when it gets cold it'll start again and it'll cycle like that even if I'm not going anywhere. That said, I do allow it to start immediately in most parking lots b/c that low speed travel in the first 30 seconds to 1 min. is more fuel efficient than if you were to be in EV until the moment you pull out into normal traffic and immediately have to accelerate up to speed.

And that's pretty much it. Beyond that it's fun but won't do much if anything to help FE and more often than not it'll hurt it.

 

<div class='quotetop'>QUOTE(bigmahma @ May 7 2007, 09:11 AM) [snapback]436795[/snapback]</div>

I'm not 100% sure what you're asking me...but let me explain how I would use EV in this situation.

First of all start the car and let the ICE go through it's normal warm up. This is important both b/c you don't have enough battery to go a whole 2 miles one way and b/c the more warmed up the ICE gets on the outgoing trip the warmer it will be when you start the home bound portion of the trip and THAT'S when you're going to make-up the FE losses you suffered on the out bound portion.

Second, once you've gotten warmed up (probably after a mile to 1.5 miles depending upon speed, traffic ambient temps, etc) you can start thinking about using the EV button....if you're approaching a stop and the car doesn't drop itself into stealth as you drop below 35mph then I'd hit the button. If, at that point, traffic is creaping you could stay in EV. But once traffic gets moving again, even if it's only ~1/2 mile to the grocery store I'd turn off EV and let the ICE run...if it's 1/4 mile or less use your best judgement. If traffic speed is slow, if the battery SOC is at 6 bars or more (over 60% actual SOC) then I'd probably consider EV mode to glide into a parking spot.

Third, the homebound trip could be a little different. Assuming a shortish shopping trip your car may still be near 150 degree ICE temp. I'd definately let it start right away in the parking lot, try to get up to speed on the road and mazimize my Pulse and Glide techique on the way home since the car should be ready for that. Use EV mode as needed under the same conditions in my first post in this thread. Do not use EV just to extend electric only distance though.

 

<div class='quotetop'>QUOTE(darelldd @ May 7 2007, 10:08 AM) [snapback]436834[/snapback]</div>

This is debatable. I chose to let it warm up while driving at low speed in my driveway and parking lot. Some of the Japanese hypermilers choose to sit and let it warm up before driving feeling this allows the low rpm warm up condition to keep the car in the more efficient range as it prefers to do anyway.

 

<div class='quotetop'>QUOTE(darelldd @ May 7 2007, 10:22 AM) [snapback]436844[/snapback]</div>

They're using things like CAN-View, the Super-Midi and other devices to monitor fuel consumption for the trip/first mile, etc. Remember that the consumption graph is a very weird little meter that's fine for looking at trends, but not the best for showing actual vehicle performance if you're alternating speeds, and doing other techniques.

And, again, I prefer to drive rather than sit too, but I try to get out of Stage I before I have to get up to traffic speed if at all possible and that takes 30-60 seconds (usually) of speeds generally below 20mph and gentle accelerration to avoid heavy battery drain.

 

<div class='quotetop'>QUOTE(JimboK @ May 7 2007, 12:01 PM) [snapback]436913[/snapback]</div>

Yea, stop sleeping with the landlady...you get better FE with the fiancee!!!

 

I would say that if that 1/2 mile is all coasting/gliding and ICE/power isn't necessary to carry you, but the ICE tends to run anyway then the EV is convenient...my house is about 1/4 mile from the top of my road and occasionally I can't get into stealth, but I'm just coasting/slowing until I hit the garage. I'll hit the EV button if I can't get into stealth.

Again, I do not recommend using it with the logic that you're going to recharge at start-up anyway, that' not efficient.