Tim, don't forget about regen also. My program to get the best mileage starts with the ICE getting to speed, then letting that momenum to assist in charging the HV battery with the small generator. The objective is to reduce the amount of time the ICE is running. On the highway, cutting back on power useage may help a little, but driving technique will help you the most.

When you take the battery down to force an ICE restart, that battery will suck up a charge better than any other time of it recharge cycle. Two fake shifts in "L" gear will get you back to EV the fastest by combining the juice from the small generator and heavy regen. from the traction motor.

As soon as I get a restart from a low battery, I find that getting to 30mph or higher and doing the first long (5mph drop in speed) fake shift ASAP works best. If you give the small generator time to recharge the battery before that first fake shift, the ICE may shut down before the second fake shift. I like to give the battery its juice from the traction motor without a shutdown of the ICE first. In most cases, the battery is still to low and not ready to allow the ICE to shutdown to go EV at that point. You then can accelerate slowly and do the second fake shift in "L" at a speed less than 43mph to shutdown the ICE at ~40mph. This is when I shift to "N" for the glide in EV. If you have to maintain higher speeds for speed limits and traffic, your back to slowly charging the HV battery to its limits with the small generator until you find speed and traffic for EV again.

Taking advantage of EV and using the fake shift in "L" for recharging the battery, gets me much better mileage than cutting back on a few watts.

GaryG

 

You get better gas mileage so there is no doubt your system must work. But it must work because you are ultimately doing a more efficient job of recapturing braking energy, more efficiently accelerating and wasting less gasoline on an engine thats idling while you are coasting. All the power comes from the ICE at some point and regen is just a recaputure of energy that would have been burned off in friction in the brakes (or that pushed in there with the ICE charging it directly).

In the end.... the amount of energy (ICE, generator, battery) (converted to watts) that it takes to propel the vehicle forward, will dwarf the 60W used in the bulb in the tail lights and therefore I can't see how the MPG savings will be at all measurable.

You are right though in that my first paragraph seems to imply that engine charging is the ONLY way the battery charges and of course its not.... bad phrasing on my part.

Everyone's welcome to try of course.

 

Tim - your thinking is hurting your MPG. You need to change your paradigm with this vehcile. All your years of experience are working against you.

You may be getting poorer results than me because of your way of thinking.

On warm nights, my ICE is running about 12 minutes per hour of city driving.
My ICE is NOT running most of the time so it is NOT avaiable to recharge the battery most of the time. Lamps are on full time, drawing power the whole time, while recharging is only once in a while.

You also need to consider that lower "threshold" that forces the ICE to come on when the HV battery drops below this level. If I can keep 15% more juice in the battery at stops, when I'm in EV mode and zero charging is happening... then I'm going to avoid unnecessary start-ups when I'm standing still at 15% more stoplights.

I can't get lower than 36 MPG these days, and get 40+ MPG without even trying hard. ( one passenger most of the time, no extra cargo )

It's 10'F with 5" of snow all around today, and just got 42.0 MPG on a 10 mile trip. You can't argue with results. Plus at 10'F the Low Gear trick does not work, because the battery is too cold to take that surge of regen. Thus in cold, conserving watts plays an even larger role. Contrary to popular belief, the HV battery is NOT very large, and does NOT have much capacity... only slightly more than the 12v underhood battery.

-John

 

No offense is taken but I do get 29-31 in the 4WD with my tires at factory 35PSI and driving only 9 miles to work one way (and a short trip to lunch each day). I don't get EV mode until I'm halfway to work. The 29 number seems to be winter, the 31 number was the summer. If I end up going around town after the engine is warm my average gets up to 35MPG.... The only "trick" I use is the "fake shift" to kick the engine off early.... I'm not doing too bad actually.....

Just remember that 1-2MPG at night includes the headlights... the headlights draw significantly more power (espeically the high beams) than the tail lamps... so even if night driving is 1-2MPG you won't see that just from just the tail lamps...

 

Of course... that's why I mentioned a 15% savings and not an 85% saving!

I'd love LED headlamps, but the brightness is just not available... yet!

Plus avoiding even a few extra re-starts I'm sure eclipses just the wattage saving alone... and that's the big advantage. After all, running the engine standing still gives 0 MPG!
-John

 

The funny thing is the way I drive I can't remember when I've had the engine come on to charge the battery. Its happened maybe once or twice just before I get to my garage. Most of the time it kicks on in my case to keep the catalytic converter warm. My battery symbol has hit bottom only once or twice. And I'm doing farily well MPG wise. I could probably do better if I tried, but I've always been too lazy to put that much effort in it.

From other posts that seems kinda counter intuitive in that supposedly when the engine does charge it really kills your MPG while doing it... so if that were true you'd think that if yours has to kick on very often to recharge your battery because of your driving style it SHOULD be killing you... but obviously it doesn't seem to be doing that.

 

As GaryG pointed out, when the HV battery is very low, it charges quicker ( can take more amps for example ) then when it is say 50% charged.

Therefore, you can "restock" your battery "reserve" in fewer minutes when it is empty than when it is half empty.

Running it 0 to 50% seems better than running it 50 to 100%.

Though there are many techniques, the goal to big savings, and I'm sure GaryG will agree, is to have the ICE off as much as possible.

-John

 

One of the pitfalls of living in a congested city....

Slow acceleration may get me shot. Red lights on every corner....who has a chance to fake shift or recharge while driving. I can't tell you how often my engine comes on just as I coast up to a light.....argh.

I was happy getting 30-31 in the fall....until that **** winter blend yanked me down into the 20's!!!

 

Tim, one thing I always do is slow to a stop in "L" for the regen and to make sure the battery has enough juice to take off in EV. If you don't have a navi to monitor the HV battery, I would still give it some regen, even if I had to kick on the ICE for a charge before stopping. There is nothing worst for your gas mileage than sitting a stop with the ICE running. I even turn the key off if I have to stop for more that ~15sec when the ICE is cold during warm-up. The bad part about the eCVT is the engine idles higher than most regular automatic transmissions at a stop.

When your downtown with a stop light every block, I kick the ICE on as soon as I leave the light to make sure I have enough charge to shutdown at the next stoplight. I keep it in "L" for any regen and to shutdown ASAP.

My commute involves going downtown almost everyday to the PBC Courthouse and sometimes I have to drive around the building many times to find a parking space. No matter what I do, my average drops in that type of traffic with stop and go. It's about 20 miles from my house, so my MPG average from a cold start on average is 48mpg during the summer and better than 50mpg during the winter here. I'm lucky that all I do is drop off completed work and pick-up new work to be done at home. This means when I get back to the FEH to drive home or to other stops, the engine is still warm and the return trip average is much better unless I get a strong headwind.

One key thing I do is choose a fast route with slow speed limits. This means going around stop and go routes as much as possible. Because I-95 get bumper to bumper near downtown WPB and even before, I can get there along the coast just as fast.

Tim, have you looked at all your routes for the best possible way to get to where your going? Even if I need to drive my kid to school two miles away, my average MPG reaches 37 to 40mpg (from a cold start) in that 4 mile round trip because of planning the best route. After two miles, I'm ready with a good SOC to wait in line to drop him off in EV. Once I get back on the road in heavy traffic, sometime I have to accelerate fast, but I manage the fake shift by keeping an eye on the vehicle distance behind me. Many times I go much faster than the speed limit to move ahead of traffic in order to go EV with the second fake shift and glide in "N".

Ethanol is another story, and I feel for those who have to put up with that crap at the same cost as gas.

GaryG

 

Gary,
I've tried it all...but I think I am just too lazy to work that hard while I am driving. As it is, my wife thinks I'm nutty for accelerating so slowly, shifting into L all the time and writing down mileage and tank info on every fill up. I have identified "better routes" but sometimes I am stuck with poorer choices if I or my wife is running late. I think the biggest problem is that I live in the city so I don't get the opportunity to warm up and recharge the battery on my way into the stop and go traffic. I turn the corner, go two blocks and the redlights start lining up.