This summer I never hit my MPG goal, a tank at 45 MPG, but I did have a nice string of tanks going with every tank above 38 MPG until now, a stretch from April to the end of September with every tank 10 MPG above the modern EPA numbers for my 4WD FEH.

It was close though, 37.5 MPG, so it's not like my MPGs have crashed, though historically my current tank is my last good tank of the year before colder temperatures drive the averages down. On the plus side, it did put me into the 34 MPG lifetime average, so I suppose I shouldn't complain too much, but it was so neat to see the numbers up there tank after tank!

 

Great job, Rich.

Can you tell us (me) a little about your commute and what techniques you use? I'd love to get these numbers.

Do you know if your pumps contain E10?

 

So that 36.7 MPG tank in July didn't count?

If it ever cools off here I should be able to top 38 again. Nonstop A/C and great FE don't go together too good.

 

Whoops! I missed that one. I suppose I could argue around it, as I stated in my trip notes, it was the tank on the way to Hybridfest, almost entirely uphill expressway driving (Which balances out with the tank after on the downhill drive back), but yeah, that tank completely slipped my mind; I added something like 4 tanks when I got back from HF, so I think it's a bit understandable.



Sure. My main commute is actually two different drives, the first part is about 27 miles one way, speed limit 50 miles per hour for the most part, while the second is 6 miles one way, speed limit 45 MPH for almost all of it. On the weekends I tend to drive about 30 miles running various errands (Bank, Grocery shopping, dinner, etc.) under similar conditions, then at the end of the month there's a bit of extra driving for end of the month stuff. Of the 27 miles, 26.8 of them are city style driving, and there's a tiny bit on an expressway.

My biggest asset is light timing and traffic management. I've long since learned the timing of the lights so that I hit them all green (or as many as possible), and with enough time for the gathered stopped traffic to clear so that I don't have to slow down at all, as well as getting nice long coasts in for lights that I know I can't make green. Generally I stop for 2-3 lights over that 27 mile drive, passing through 60 some lights alltogether. I know how many times the "Don't Walk" sign flashes before the green light turns red on each intersection, so I can even adjust myself to make sure I make not the next light, but the light 6 miles or further down. As for driving itself, I know what speeds I have to drive, from 47-52 MPH to make all those lights without needing to slow down, and generally set the cruise control, as after years of trying I can only get a tiny bit better on my own, and sometimes a little worse. When I do have to stop, I use L right away to get my speed down and charge the battery, as well as watching the power screen to make sure I don't overcharge the battery or take steps to prevent overcharging from happening, and start the brakes and L together when it's appropriate, finally shifting out of L when I've come to a stop, or close to it. (L doesn't cause any additional charge under 5 MPH or so) During start up, I'm quick to accelerate in EV, doing what I call EV Creep; where I'm closing in on the car in front of me, but as he speeds up I maintain in EV for a while longer causing the vehicle gap to widen before my ICE comes on, generally that allows me to get up to 15-20 MPH before the ICE pops on, save for a single light that I stay in EV the entire distance for because I know there's a delay before it changes.

In the winter, of course there's the changes in driving style that need to be made; L becomes essentially useless, and in the earlier model FEH's I have to do some switching about to turn of the defroster to get the ICE off right away, while double tap comes back into play, as well as some other differences. Often after or during bad weather instead of trying to modify my speeds to make lights, I'll instead know which ones I won't be making and planning ahead to stop for them, maximizing ICE off and safety to stop accordingly.

Yes, my pumps contain E10. I actually don't know of any in my area that aren't actually.

 

Rich, thanks for taking the time to type all that out. Looks like you've got a great commute for the FEH (45-50 psl is a sweet spot for the FEH) and your effort in knowing your route so well pays you big dividends.

 

What is "overcharge"? Coming down off of mountains a couple times I've had my battery meter filled all the way to the top in my '09, but I was thinking this was a good thing to allow me to use EV more?

 

I'm not the best to chime in, but I was running out to lake mead and anyone that has done the downhill swing from Boulder City to Boulder Beach or Hoover Dam can atest to the steep downhill grade.

I had my battery so charged, becuase I was using L just to keep the car at a manageable speed (the speed limit 55) and after I had the battery fully charged (at least from looking at the NAV screen) for about 2 minutes the RPMs actually started to REV up to slow the car and it would no longer allow any regenerative braking. At this point even when I tried to manually brake the car (to induce a recharge) it would only use conventional braking...

 

Hi Rich - Follow-up question:

I feel like the "at-speed" techniques to improve fuel economy in all cars have been talked about a lot. Can you provide some insights regarding acceleration? For me personally, I've had a lot of success by backing off the pedal on the highway, keeping up on my FEH's regular preventative maintenance, and staying in EV where I can. But I feel like my tank Avg MPG drops too much during acceleration; especially when merging on to the highway.

At first glance it looks like their are two schools of thought: one that says "slow and steady acceleration is best, keep the RPMs down as much as practicable, and that will save energy and thus be more fuel efficient;" and the other that says "just get to your steady-state speed as fast as practicable, so you can start doing those efficient driving strategies as listed above." Could you share any thoughts about how to best get up to speed? Thanks!

 

Trekwars did a good job with his answer. When I talk of overcharge, I don't in any way mean recharging, I mean having far too much energy for even the HV battery to handle.

There are times when a lot of L and slight braking for a nice long distance stop with an already well charged battery will result in so much energy being recaptured that the system can't handle it, as a result, it spills off that energy by spinning the ICE, shunting the electricity captured by the regenerative brakes into the ICE rather then the HVB. By watching the battery levels, I can shift out of L back into D before that happens, modify my braking technique to prevent such a spillover.

Having a fully charged, or "fat" battery as I call it is great, espeically once the system is at optimal temperatures, as you can get some great EV pulses up to speed with it.


I do both actually. I keep the RPM's down and get up to speed as fast as possible. Sounds confusing, doesn't it? I use multiple "Fake Shifts", that is, a quick let off on the acclerator to allow the eCVT to make an adjustment and the tach to drop, then reapply, and repeat the process multiple times. My goal is to get up to speed without dilly dallying, but also to keep the RPMs under 2000-2500 as much as possible. (Obviously at high speeds that may not be possible, but as often as possible.) I may "Fake Shift" 6 or so times on my way to 50 miles per hour from a stop.

As for the highways, I use the traffic as my guide. If traffic is light and there are no oncoming vehicles as I'm merging onto the expressway, I'll keep the RPMs and the speeds down, getting up to 50 or so MPH fast and efficiently, but then adding the rest, say up to 65 MPH gradually, with one last "fake shift" at speed to make sure the eCVT has me at its most efficient. On the other hand, if traffic is oncoming at speed and I don't have too much choice in the matter, then I'll try to high speed pulse and glide a bit, getting up to say 65 MPH quickly and work the ICE slightly, but then ease off and try to get in a slow patch of traffic and coast down to speed, say 55 MPH or so or whatever my speed objective is (For expressways I like to either observe the Truck Speed or 55 MPH). Obviously for congested traffic, I just go at a normal rate, either with a nice EV glide or without too much hurry merging onto the traffic laden road.

 

That does sound confusing ... and yet makes sense. Before getting on this message board I'm not sure I'd have any clue what that meant, though

Thanks for the info - I'll have to try that strategy, and really work on it for my next tank. Best,
- Andrew