[Oeva-list] Full trip report

Alan Batie alan at batie.org
Wed May 18 23:56:27 PDT 2011


Hopefully not too long-winded and that there's some useful in it;
Carwings finally got the last of my trip data on the website today:

Last weekend, I drove my Leaf from Corvallis, OR to Portland, OR
and back in a test of freeway range ("we have range anxiety so you
don't have to!").  I already had a pretty good idea of the capability,
and that turned out to be pretty close.  I'll start by describing
the trip, followed by data analysis of the info from the dash, what
the car reports to Nissan and what a couple of the charging stations
report.

Corvallis is about 85 miles from Portland (at least from my house
to the 50kw DC Fast Charge station in the World Trade Center parking
garage where the PGE headquarters is located).  In between, there
were known Level 2 (240V, 3kw) charging stations at Linn-Benton
Community College (12 miles from home), a PGE facility north of
Salem (32 miles from LBCC), a possible L2 at Salem Nissan (4 miles
south of PGE) and Tonkin Nissan in Wilsonville (27 miles from PGE).

I left on this trip around 11:30am Saturday, and while I planned
to do some of it at 70, since I thought I'd be pushing the range
much of the time, I stuck to the speed limit (mostly 65) the whole
way.

I didn't know if Salem Nissan had a station, and 44 miles was getting
close to my expectation of a 50 mile useful range on the freeway,
plus I wanted to use the LBCC charging station just so it got some
use, so I stopped there for about a half hour.  For that 12 miles,
the range estimator went from 100 miles to 69 miles (31 mile drop),
and the battery level dropped 2 white bars (there are 10 white bars
and 2 red bars; it will turtle (speed limited to 35mph) around the
time you hit the bottom red bar and I consider the white bars to
be the "useful range", as does, apparently, Nissan in reality (as
opposed to the marketing) judging from the colors).  Henceforth,
when I say "bars", I mean "white bars".

Carwings (the service where the car uses AT&T's cellular network
to log energy information to a central web server) reported 3.0kwh
used, with .4kwh regenerated for a net of 2.6kwh or 4.5 miles/kwh.

After the 1/2 hr charge, I had 9 bars and a "77 mile range".  While
waiting, I called both Salem and Wilsonville Nissan and confirmed
they both had charging stations ready and waiting.  Since this was
an exploratory trip and wanting to "show the flag" as well as check
things out, I stopped at Salem Nissan, planning for a brief stop
and then a longer stop at PGE, with it being closer to Wilsonville.
When I got there, I was at "52 miles" (25 mile drop) and 5 bars
after 29 miles of travel.  Carwings reported a net consumption of
5.5kWh.

The Salem people were very friendly and chatty, admiring the blue
color and talking about the Leaf and asking about how I liked it,
etc.  I noted to myself that there was a DQ and AM/PM across the
street, convenient while charging, then headed up the 4 miles to
PGE.  After 1/2hr charging, I was up to "60 miles" though still 5
bars.

When I got to PGE, I was back down to "53 miles", still 5 bars, but
when I plugged in to the charging station, the only thing that
happened was the car beeped, indicating it knew I'd plugged something
in.  I tried unplugging and plugging, and tried putting a debit
card in the card reader, but the blue light stayed off (while the
110V side was lit) and the screen and lcd status indicator remained
unchanged.  Later discussions with Shorepower (the station manufacturer)
suggest that I probably didn't have the connector fully engaged,
as they verified later that the station was operating properly.

As it was, I headed back to Salem Nissan to get the charge I needed
to get to Wilsonville.  I forgot to take a picture when I got back
to Salem, so I don't know the state, but I started charging, went
in to tell them the PGE station didn't work and that I was going
to go get lunch (it was 2pm by now) and they directed me to "Almost
Home" a couple blocks towards the freeway (and it was indeed good
diner food...).  Carwings reported .8kWh for the trip to PGE, but
for some reason it did not log the return back to Salem Nissan.
Since I backtracked, I assume it was another .8kWh...

A little after 3pm, I had "65 miles" and 7 bars.  Since the range
estimator had been reasonably close and it was only 29 miles to
Tonkin, I figured that was good enough.

My original plan had been for it to be half full, I'm not sure what
I was thinking because I was pretty sure it wasn't going to get 60
miles/full charge on the freeway, but in fact, since I got there
with 2 bars to spare, that would have been about right.  I'd also
originally planned to go directly from home to Salem, using the
full "white zone" and to charge for two hours to make it to Wilsonville
from there.  Taking the 1/2hr at LBCC and the 1 1/2 hr at Salem,
that estimate was right, though using 2 bars to LBCC + 4 bars to
Salem is only 6 bars, so that was better than I expected.

When I got to Wilsonville at 3:45, I still had "27 miles" (down 38
for 29 miles travelled) and 2 bars, and it's only 16 miles to the
WTC from there, so I went directly to the friend's house, where I'd
planned to visit while charging, thinking I didn't really need to
charge, but then I got to thinking about the "twice the distance"
and particularly the hill I had to go over to get into Portland,
and decided I'd better go over and charge for a bit.  I'd planned
for about a 15 minute boost, but realized I needed an hour's worth,
so we had his wife come pick us up and went back to his place for
a bit.  Amusingly, because of the low speed driving around Wilsonville,
by the time I got over to Tonkin, it was up to "29 miles", gaining
the 2 miles instead of losing them ;-)

At 5pm, I had "40 miles" and 3 bars, and 20 minutes later, at the
WTC finally, I had "25 miles" (down 15 after 16 miles) and 1 bar.
Interestingly, I picked up 4 miles coming down the hill from Capitol
Highway down to downtown Portland, going from "25 miles" at the top
to "29 miles" at the bottom.  And you definitely notice the suck
going the other way too ;-)

So, 6hrs (plus 1/2hr to refill to "83 miles", 8 bars at the WTC)
vs 1.5+ hrs...  Definitely need the fast charging station in Salem!
But since I only used the actual mileage on the range indicator,
and 2 bars, getting to the WTC, I probably *didn't* actually need
to charge at Tonkin...

Once I made it to Portland, I was getting together with a group of
friends in Camas, and the spending the night with some other friends
in Hillsdale:

WTC -> Camas (I84/I205/Hwy14, 20 miles actual, "83->50 miles" [33
range miles], 8->5 bars) Camas -> WTC (20 miles actual, "50->18
miles" [32 range miles], 5->1 bar)

Oddly enough, the second charge at the WTC only went up to "68
miles" and 7 bars, stopping early for some reason.  The battery
temp didn't seem high, but I'd been out walking on the waterfront
for 40 minutes, so if that was it, it would have had time to cool
I suppose.  Since I wasn't planning on doing a lot of distance
before charging up again to head south on Sunday, it was plenty and
it was 11pm, so it was good enough.  Up to Hillsdale to spend the
night (4.4 miles mostly uphill, "68->49 miles" [19 range miles!],
7->6 bars)


Sunday:

On Sunday, after visiting with my friends for a while, I was planning
on taking in a play at Triangle Productions (www.tripro.org), who
I do the web site for.  I'd thought about using the 110V charger
at my friends' place, but since they live nearly at the top of the
hill and Triangle is essentially all downhill (well, some flat after
getting down), I couldn't resist the chance to see how much regen
I would get --- nearly a kWh as it turns out: for the 6.9 miles to
about Sandy/17th, I used 1.4kWh and regened .9kWh, for a net of
only .5!  Data: 7 miles actual, "49->56 miles" [-7], 6->5 bars

I'd originally planned on going directly to Wilsonville, but with
it only half charged, I decided to do the 80% at the WTC: 2 miles
actual, "56->67 miles" [-11], 5->5 bars.

I didn't expect to spend very long at the WTC, figuring about 15
minutes, but since it was over half full, it went ahead and filled
it all the way up, taking about 40 minutes.  Actually, at 99%, I
noted that it was only doing 8A, about 3kw and figured it wasn't
going any faster than the L2 charger would at that point, so stopped
it after putting in 6.9kWh, leaving with "93 miles" and 9 bars.

I got to Tonkin at 5:15, down to "57 miles" and 7 bars, visited
with my friends there until 8pm (though the car said it would be
done charging at 7:30pm).  At 8, it was full with "81 miles".

I got back to Salem Nissan at 8:40: 30 actual, "43 miles" [38] and
4 bars (using 6 instead of the 5 it took coming up).

I had planned on charging up all the way in Salem, but since I knew
I could stop at LBCC, only 29 miles away, and having a better feel
for the range, I stopped at 10pm with "47 miles" and 6 bars.  One
interesting thing is that since I was plugged in and it was chilly,
I turned the car on and ran the heater while I was charging.  Each
"car turn on" generates a separate Carwings log entry, so that
showed up as its own record: .9kWh for the hour+  It didn't need
to run all the time, but A. that means it's well more than a hair
dryer ;-) and B. it's a heckofa load!  Not that that's a surprise...

When I got to Albany, I still had "27 miles" and decided to push
my boundaries a little, as I *should* be able to make it home, and
turtling the last few miles wouldn't be a disaster as I'd be in
Corvallis then.  I did slow to 60mph for the 7 miles of freeway
between Albany and the Corvallis exit, and 50mph on the 10 miles
of 55mph highway to Corvallis, though when I got near Corvallis, I
could see I would make it ok and sped back up.

Amusingly, the GPS in the Leaf doesn't trust the range estimator
any more than I do: when I got off the freeway, the GPS showed "11
miles to go" and the range estimator said "19 miles".  At that
moment, the GPS voice piped up "You may not be able to get to your
destination" ;-)

In fact, I *did* make it home with no white bars, but both red bars,
and the range showing "10 miles".  My charging station took 5:50
and 20.5kWh to charge it back up over night.


I've collected the data into a spreadsheet at
http://alan.batie.org/leaf/20110514-pdx.html

For most of the charging, I've estimated based on 3.3kW, though the
WTC fast charger tells you (except for the second charge Saturday
when I forgot to note it), as does my Blink at home.  That's high
when doing a full charge though, as batteries just can't take it
at full rate near the end of the charging cycle.  The only case of
that was at Tonkin on the way home though.

The trip home did use noticeably more power; interestingly I've
noticed my gas mileage tends to be slightly, but noticeably, lower
going south vs north in gas cars as well.  I figured it is either
a tendency for winds to be out of the south or that I'm usually
heading south at night and temperatures have an effect.  I probably
did use the heater a little, but I tried to minimize it, and the
fill up over calculation at wilsonville doesn't explain all of it,
as the diff is nearly the entire amount used there.



The point of the exercise, however, is "how far can I reasonably
expect to go on the freeway?", and "how much do I need to charge
up?"

The first thing that stands out is the segmented bars are much too
coarse, and the range estimator far too variable, to be of much
use.  I really want an option to have the range estimator display
"remaining kWh to turtle".

The next thing is that if you believe the Nissan specs and Carwings,
I should be able to go all the way from Corvallis to Portland on
one charge: a 24kWh pack, about 20kWh consumed.  With 12 bars,
that's 2kWh/bar, and 20kWh should just use the white bars.  I charged
for 3 1/2hrs and still only got home with the red bars.  No way
it's making it all the way on one charge.

That said, you can't just add up the bars --- they're 10% each, and
if you charged to just barely turn one on, and drove till one just
barely turned off, vs charging to almost turning the next on and
driving until the next one was going to turn off, that's a 20%
difference.  There is a *vast* amount of slop in them, and that's
for *each* segment.

Still, the charging at Salem for a little over an hour raised 2
bars but only 4 range miles.  That makes me think (unfortunately,
I wasn't paying close enough attention while it was charging) that
it started just barely into 4 bars and charged just barely into 6,
meaning the 40 miles home used between 5 and 6 bars.  Since I slowed
down a bit at the end, let's call it 6 bars (which is what it
actually showed).  That means 6.7 miles/bar at 65 or 67 miles range.
Tonkin is 70 miles from home if I don't detour to LBCC, so I think
I *might* actually be able to make it at 60mph, which is doable if
I stay in the truck lane, then I'll need a couple hour charge to
make it into Portland.

Looking at it another way, if you assume 2kWh/bar, and Carwings
reporting that I'm getting about 4 miles/kWh, that means each bar
should be 8 miles, which is in the ballpark.  It would be nice if
I really did get that ;-)  I could easily make Tonkin, and should
*just* make it to the WTC before turtling (85 miles actual vs 11*8=88
range).  I don't believe it ;-)  I might try if there were a place
to charge in Woodburn "just in case".

Instead, when I go up to PGE to double check the station there
Saturday, I'm going to go 70 with traffic to see how that affects
things.  We'll see after that, as I should have a good value to
"prorate" then...

It is interesting comparing the Range Distance with Actual: it's
not too bad if your route is consistent.  It was even pretty spot
on for the segment from Tonkin to the WTC, where both are close to
the freeway.  Though that short of a trip, you'd think those couple
of miles would have a bigger impact, but I'd just come up a lot of
miles on the freeway.  Going the other way, it was clearly impacted
at the beginning by all the low speed driving I did in town before
hitting the freeway.  Again, by the time I got to the end of the
trip going home, it was pretty much spot on, using fewer range miles
because I slowed down at the end.

The range estimator is just inherently useless because it doesn't
know where you're going.  A friend suggested that it be tied into
the nav system so you can tell it where you're going and it can
make much better assumptions.  I'd just rather it told me kWh's
remaining, to the 10ths, since it seems to know that info, but if
using the nav system made it actually accurate, that would be nice...

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