Posted by Elmo P. Shagnasty on April 28, 2011, 9:49 am
no, I see your pretty charts and see lack of data.
I see you stacking the deck, as it were.
BTW, have you ever driven your Prius in 10 degree weather on short
trips? Or in 10 degree weather on the freeway for several hours against
a 20mph wind?
Where's THAT chart?
Posted by bwilson4web on April 30, 2011, 6:20 pm
Sad, the charts are the data in a graphical form. They also show the
degree that hybrid skeptic will go to deny reality. Data sources have
been provided. But you might want to go there
. . .
Just use the same charts as before including the table about about air
density effects. At 15F, got 47.5 MPG in our NHW11, 03 Prius. That is
what these pretty accurate charts allow us to do, confidently predict
performance rapidly and without having to be rude about it. But since
you've asked about my driving, I've had an interesting experience
Power is off in Huntsville Alabama and most of North Alabama. This
means every traffic light intersection has become a four-way
stop . . . miles and miles of four-way stops. So yesterday I was in
Decatur, about 35 miles from Huntsville which I reached at 62 MPG.
There I bought 5 gallons of gas for our 03 Prius that has a 1kW
inverter so we can 'camp out' at home.
My Prius UPS:
I'm burning a little over 1 gallon of gas per day. In fact, I ran an
extension cord to my neighbor who also had lights and a small TV last
night. Then when the temperature dipped into the 50s, I started up the
fan in the gas furnace and warmed up our house for my wife's comfort.
Now this is something an ordinary gasser or diesel fails at because
they only generate electric power when the engine is running. The
Prius engine puts a charge on the traction battery and then shutsdown.
The traction battery continues to provide power for the inverter until
the charge gets low enough for the engine to startup. So our
neighborhood has the cicada sounds of little generators rumbling
away ... making a boat load of carbon monoxide and having to be
refueled and maintained. In contrast, the Prius has a catalytic
converter and effective muffler. Folks don't even hear it unless the
engine happens to come on and even then, it can't be heard beyond our
While I was in Decatur on Friday, some parts still don't have traffic
lights and to drive out of town, my wife's Prius ran 72 MPG for the 8
miles it to reach the highway. It was nothing but stop-and-go traffic
which is death to any gasser or diesel mileage.
So my fine feathered Prius skeptic, how is your mileage in say 10
miles of stop-and-go traffic every 1/10th mile? Choose your weather,
it doesn't matter, the Prius just wipes out ordinary vehicles. But
thanks for askin'
Posted by bwilson4web on April 26, 2011, 11:17 pm
Local conditions applied, wet when it rained, dry when it didn't,
cooler in the winter and hotter during the summer. <grins>
Facts are the VW diesels, a much smaller compact car, got it's Elmo
whipped by the Prius and lost two-of-three falls with the Insight.
What a pathetic, weak, Shagnasty assertion.
Posted by Elmo P. Shagnasty on April 27, 2011, 12:07 am
You've never even experienced 15 degree weather, let alone driven your
Prius in it for short trips and then for longer trips on a highway
against 20mph winds.
And done the same thing with a VW diesel.
Posted by bwilson4web on April 27, 2011, 12:33 pm
Getting desperate, are we? Of course you could have just asked nicely
instead of being an ass.
It turns out I've made a study of Prius cold weather performance at
all temperatures. Yet my annual MPG still runs 52 MPG. But looking at
some of the early data from GreenHybrid.com:
Prius cold weather performance has received a lot of attention and the
latest, ZVW30 model, has an exhaust heater for the coolant:
My wife's 2010 Prius handles cold weather very nicely so the
predominate effect is air density. Colder air is denser than warm air
and the mileage falls off following the temperature-density curve:
". . .
Excellent! I used your data to make this table:
TempF TempC density_kg/m3 %_density MPG
15 -9.4 1.34 111.7% 47.5
32 0 1.29 107.5% 49.3
68 20 1.20 100.0% 53.0
85 29 1.17 97.5% 54.4
There is very good agreement from my informal measurements across the
temperature ranges of this trip. Whenever the temperature was above
freezing, the North American MFD would show 5 minute bars equal or
above the mid-range, 50 MPG scale. But once the temperature dropped to
freezing or lower, very few of the bars would exceed the mid-scale
On the way out of town at 15F, I saw MG1 reach 80C while MG2 stayed
about 12C cooler. I've recorded some data and will analyze it later.
On the trip I was thinking that cold weather would be an excellent
time to test aerodynamic modifications. I briefly thought about taking
the water noodle, radiator block out but I was in a hurry to get home.
But we are expecting another cold front later this week.
. . ." posted in "Prius_Technical_Stuff", Jan 21, 2008
It turns out that there are a few simple rules of Prius cold weather
driving that significantly improves performance.
So which one do you drive now, the VW diesel or the Prius. It would be
a waste of time to teach you Prius cold weather techniques if your
ride is just a VW diesel. Regardless, the techniques are fairly
straight forward so I'll start a fresh thread.