50+ MPG -- A Newbie's Quest

July 4 Weekend Drive; 59.4MPG

We've just returned from a ramble up I-95 through the Middle Atlantic States
and return.

Details:
* Fri, July 4: Ballamer to Suffolk County, Long Island, New York -- 250 mi,
speeds ~60 MPH, Temps 72-84 deg F, 59.4 MPG
* Sat: Drive-about Eastern Long Island, surface roads, traffic lights, four
start-stop legs -- 76 mi, speeds mostly ~50 MPH, temps 68-82 deg F,
59.4 MPG
* Sun: LI to Ballamer -- 250 mi, speeds ~60MPG, temps 68 - 84deg F,
59.4 MPG. Note: First use of Cruise Control (CC).

Comments:
* While the 59.4 MPG is not startlingly good, it is the best I've achieved at
50-60 MPH, over an extended distance. Best previous over this ground was
57.4 MPG, IIRC. I'm feeling pretty good about it. My lifetime MPG is now up
to 49.5. (MPG readings from SCANGuage, three separate daily trips.
* Long Island is an extremely good area for getting high MPGs; almost
flat, long, low rolling mini-hills, typical Posted Speed Limit (PSL) on
secondary roads 50MPH.
* In Ballamer, 87 octane gas/petrol has been stuck at $3.99 US for three
weeks or so now. Gas on the NJ Turnpike was also $3.99. On LI, gas was
between $4.29 and $4.49.
* Almost all drivers were driving at or within -5 MPH of the PSL; 65 MPH
on the NJ Turnpike. Very few "rocket men," and those mostly SUVs, in
denial I guess.

Although we've had Amapola for 6 months and ~7K miles, this was the first
time I used the CC. Why? On one hand I wanted plenty of time to learn the
high-mileage discipline and tricks. On the other, that little stick with all the
writing and arrows on it was intimidating. It was however, from the
beginning, my plan to use CC on the return trip. I'm afraid that the results
don't say very much. On this pretty much flat route, either I'm as good as
the CC, or the CC didn't do any better than me... a toss-up as far as MPGs
go.

But, I must say, slipping along with the CC on was a much more relaxing
and enjoyable way to roll up the miles. I expect to use CC on long trips
where the topo is relatively flat from now on.

 

Re: July 4 Weekend Drive; 59.4MPG

Time for a little "thread-keeping"

Son of Gloin,

My purpose for this thread is to help new owners realize that really good
MPG figures arent necessarily a given. But, with lots of reading and
concerted effort, the numbers will come. Right now in the summer, good
numbers are pretty much a matter of course. As the temps fall in the
autumn, there be some panicky posts about falling MPGs. Those folks will
have to learn the tricks to maintain good winter MPGs which may be about
40-45 for temps in the 30s F. Ill have to go back and do some reviewing too.

a priori,

Fortunately, my MPG numbers on this trip do not support having a strong
opinion on use/non-use of the cruise control (CC). I think you've got it right,
CC does pretty well on near-flat and gently rolling terrain.

But, I found that I didn't like the cruise control itself. It controlled the speed
far too tightly for my liking. If the speed fell even 1 MPG, CC asked for a
handfull of power to get back to the set speed. On downhills, again it held
near exactly to the set speed. This constant speed travel at times seemed to
irritate other drivers who slowed slightly on up hills and sped up some --
usually +5 MPH -- on downhills. My nomination for a really desirable hack
would be one where I could dictate how fast the CC responded and how big a
departure from set speed was permissable below and above the set speed.

JimboK,

thanks for bringing reference to these other threads into this one. It is easy
to forget where you got a particular MPG strategy or bit of information in the
huge info-heap we know as PriusChat. I really value input from more
experienced posters like you, a priori, and the many others, whether
it's new info, or a reminder that there's more here than most of us newbies
and near-newbies -- me, for instance -- realize. Ill be re-reading the threads
you've posted to try to keep my MPGs climbing.

 

The following is an extract from a post I made to another thread. It has two
points: the power of the Pulse & Glide technique, and the idea that out-and-
back MPGs are far nore meaningful than one-way trip figures.

Here is an excellent discussion of hiway speed max-MPG techniques.

Pulse and Glide plus Warp Stealth in the Prius II for maximum FE … - CleanMPG Forums

Note:it is excellent for the amount and completeness of the info it presents.
It may not be easy to comprehend in one reading... at least it wasn't for me.
I found that by trying things out and rereading it, I slowly learned what was
being presented.

There's lot's of pulse & glide discussion here on PriusChat. Use the search
function with "pulse & glide" as the search term. For starters. only read
threads with Pulse & Glide in the thread title.

 

My daily commute is less than ideal. About 14 miles one way. In the AM,
home to work is essentially a down hill run, a total drop of ~350 ft. MPGs
are a function of temps, traffic, and whether I'm really paying attention.
Routinely I get 58-66 MPGs.

The way home in the PM is another matter. Of course there's that 350 ft. I'll
have to climb. But there's also a stop sign and eight lights before I reach the
high point in the trip. (It needs to be said here that I don't (yet) have the EV
mod.)

Even with temps in the high 80s-low 90s deg F, my initial coolant temps are
only ~110 deg F. What this means is that if I do nothing, at the stop sign
and the first two lights, the ICE wont stop running when I come to a stop.
Taken together, this can easily mean the loss of 1.5 MPGs per my
ScanGuage. What to do? Why find a way to kill the ICE.

So here's what I've discovered, hardly a major development, but good
enough to save those slowly leaking away MPGs. When I come to a stop and
the ICE doesn't immediately stop, I shift to PARK. Yup, you got it, essentially
dead in the middle of the road. The ICE stops in a second or so -- the
computers don't know whether I'm in a parking lot or stopped at an
intersection. Immediately the ICE stops, (per SG RPM readings) I shift back
to Drive. I've found that I can save 1-2 MPGs on the way home. When I'm
lucky, I'll pull into the driveway at 50-55 MPGs for the out and back trip --
just so long as I've been lucky with the lights and traffic, and it hasn't been
one of those all too common, "just a little bit fuzzy in the head," days.

FWIW

 

Icing on the Cake

Last night I pulled a 8 mi, 70 MPG trip at speeds between 30 and 35 MPH.

Wow!

It was a lucky conjunction of all the different pieces of the max FE equation:
* the ICE was fully warmed up
* air temps in mid-70s
* traffic was very light -- it was 11 PM
* I was able to time most traffic lights to roll through without stopping
* it was on a gently undulating route ( Joppa Rd, Perring Parkway, Taylor
Ave, Old Harford Rd.)
* little or no altitude gain, maybe -80 ft in the last mile
* I was paying really close attention -- unfortunately for my lifetime MPG,
this is not always the case.

I suspect that dedicated hypermlers probably could have gotten up to 80+
MPGs, but for me 70 was wholly unexpected... but quite gratifying.

So what? Well, in my mind, this signals the end of my Newbiedom. We've
had Amapola for 8 months now, and put on just over 11K miles, with a
lifetime FE of 50.5 MPG.

I'm still looking for greater FE, but no more as a Newbie, Nooby, Nube,
whatever.

What level comes next? Aspirant, Practioner, Apprentice, Searcher of Truth
and Max FE?

Sign me up!

 

This is a slight expansion of thoughts I posted to another thread discussing
my feelings on the relevance of the "Leaf Car" symbols used to display
the amount of regen "achieved" while driving.

All things considered, it is best to ignore the Leaf Cars.

Think of the Leaf Cars as energy dust pans that collect small amounts of
energy that individually are quite small, but if you can collect a bunch you
have something of limited value. The gas in your tank is like large
denomination bills in your wallet/pocket book. Leaf Cars are the equivalent
of change in your pocket returned after you spend one of the large bills.

Getting down to brass tacks, I've read that the total energy in the HV battery
is equivalent to three tablespoons of gas/petrol. Further, as an average, one
of the blue bars on the HV battery mimic could represent three Leaf cars. So,
without getting overly fastidious about the math, a Leaf Car represents something
like 1/10th of a tablespoon of gas/petrol. This is truly small potatoes.

Ultimately, all movement of the car comes from using gas from the tank.
Unfortunately, in the real world there are a hundred little things that intrude
on getting the absolute best FE/MPG. It is no surprise to me that I get my
best FE/MPGs late at night when almost no one else is on the road. If I could
just get rid of the stop lights and signs, I could get really outstanding
FE/MPGs.

At best, the Leaf Cars are Reality Reminders, more likely they are Tokens of
Failure.

Reality Reminders result from scavenging small amounts of energy when
you have to slow down to accomodate the real world in which you drive:
stop lights/signs, incoming traffic, a really steep hill -- remember you
already have or will have to climb the upside of that hill trading gas,
chemical energy, for potential energy which can only be fully realized by
rolling unimpeded down the hill, and on, and on until you roll to a stop.

Tokens of Failure occur when you have to slow dow due to misjudging time,
speed, and distances. This is just another way to waste gas.

Basically, that Leaf Cars occur in day-to-day driving is understandable, and
even a good thing. But for the most part, you want to avoid creating the
little Leaf Cars if you're after good FE/MPGs.

A better measure of doing well would be the ratio of time spent moving with
the engine not running -- in a no arrows glide --against trip time when
moving -- to be meaningful you wouldn't count time when stopped with the
ICE off, that's a standard feature of the HybridSD once it's warmed up.
(I understand this can be coaxed out of a CanView set-up. I'm pretty
sure you can't get it as an XGauge on the ScanGauge.)

 

These are thoughts I posted in another thread on the question,
"Does it make sense to shift to neutral during driving?"

Since the subject has to do with FE/MPGs, I'm adding my thoughts
to this thread as well

There is additional comment on this question here:

http://priuschat.com/forums/fuel-ec...ral-during-driving-post766033.html#post766033

 

Here are my ramblng thoughts taken from another thread discussing
the pros and cons of intentionally running down the HV battery State
of Charge, SOC, at the end of the day.

Part 1

There was a follow-up as well. As this is longish already, I'll make that
a second post.

 

Part 2

 

JimboK,

Thank you for your comments. You are always :welcome: here.

As to the use of SOC on start-up, my definition of "huge' is probably
atypical. I monitor SOC with my ScanGauge and actively fiddle things to
stay around 60%. The SG shows SOC in 1/2 a percentage point steps. To
me, a 5% SOC reduction -- 10 steps -- is huge, even though on the SOC
meter on the MFD there may be no change shown.

You say poe-tay-toe, I say pah-tah-toe.