MPG... Anyone Else Backward?

I once averaged over 75mpg in one 5 minute stretch in the city. Basically, I went from one stop light to the next with only battery power. There were about 5 lights and since there was not much traffic behind me, I just leisurely went to the next light.

 

Obligatory Dr. Fusco plug:

http://priuschat.com/forums/kb.php?mode=article&k=23

The EPA "city" test conditions are quite unlike the slow, stop-and-go most of us think of as city driving. In real-world driving, many Prius drivers get better mileage on the highway than in town. (Including me, though when presented with EPA-like conditions, I get EPA-like results.)

The EPA number I REALLY don't understand is the highway number. I don't know how you could possibly get as little as 51 mpg in EPA-test conditions.

 

I get much better mileage on the freeway than in town. Glad I'm not the only one.

Jan

 

I got 56 mpg on my first tank, and its the last time I've ever done that well. I wouldn't worry too much about the first tank, just the rest of them. Unless you have hills or a lot of stop and go traffic it should get much better.

 

If the techs (or whoever) drove 9 miles at 13.9 miles/gallon, then they burned 9 / 13.9 = .65 gallons of gas going the first 9 miles.

If you have a total of 250 miles at 36.8 miles / gallon, then you (and the techs) have burned 250 / 36.8 = 6.79 gallons of gas in 250 miles.

So if you subtract, you've burned 6.79 - .65 = 6.14 gallons going 250 - 9 = 241 miles, for a total of 241 / 6.14 = 39 mpg. So you're pretty close to the 40s.

 

I've had my car one month now. My initial ODO reading leaving the dealer was 7 miles, and the initial mileage was around 10 MPG. My one-way commute is 11 miles, mostly flat, and mostly freeway. The average temperature was 55-60 degrees. I managed to get the mileage up to 45.2 when I refilled with two pips on the gas gauge. In the four tanks since then, the mileage has been around 45-46 except on the last tank (see below).

What I found is that ambient temperature makes a big difference. On the southward leg of our vacation from the SF Bay Area to Disneyland, a stretch from Santa Barbara to Anaheim was warm and sunny, maybe 65 degrees. I averaged 53.4 on that stretch that included a climb of the Santa Monica mountains and gridlock around downtown LA.

On the homeward leg, we encountered pouring rain with temperature around 50 degrees. The mileage averaged 40 for most of that stretch. After a couple of commutes earlier this week, that tank was 42 MPG.

I'm looking forward to summer temperatures.

I have had some 5-minute averages in city driving around 60 or so with a warm engine. I've been practicing pulse and glide. My freeway driving with a warm engine typically has 5-minute averages around 50. If only I could avoid the warm-up stage :lol:

 

Winter sucks for those on short trips. Initial mileage can also suck if you are in warm-up mode at lights, or 'stop and go' a lot during those very few miles.

Mileage in the city varies considerably depending on conditions -- I have had >100 MPG over 5 minutes while warmed up and moving CONTINUOUSLY at 30-35 MPH, but that was the speed of traffic, it was flat and level, and everyone kept moving without stopping, so it was easy. Stop and go city mileage sucks on short trips in winter because the car is in warm-up mode most of the time.

You are in Delaware (thanks for setting your location!), so if you don't have long trips on average you probably won't see 50 MPG+ until spring, I'm afraid.

I get in the 40's unless the temperature gets very cold, then I struggle a bit, as my average trip is only 5 miles or so. Mileage mostly depends on how far you average on a trip, as the shorter the average trip, the bigger the impact of cold weather.

 

you just have to have a real light foot on the pedal, and you can get up to speed with electric-only. of course if someone is behind you, you gotta step on it. i got 47MPG going to work and 48 coming home today. in the city though i've been over 50 regularly.

however, i've read here that the right thing to do is just get the car up to speed by stepping it down a bit (thus starting the ICE), and then back off the pedal, then lightly push the pedal to either glide (neutral) or get the electric motor only engaged. the idea being that if you run on batteries too long that the computer will be obliged to recharge it later, which will cut your MPG, so you might as well run the ICE a bit.

today when i came off of 237 at great america, i regenerated a bunch of power coming down the offramp. then i managed to stay on battery only all the way down great america to bunker hill! it was awesome.

my dad just got an 06 honda civic hybrid and i drove that to work 2 days this week. it only got 43MPG under pretty much the same conditions (42MI trip down 880 to 237)

also, i think someone already answered this, but here's the formula to get the "trip MPG" if you know the starting and ending miles and MPG:

mpg_trip = (miles_end - miles_start) / ((miles_end/mpg_end) - (miles_start/mpg_start))

[all the highway names are from the bay area in CA...]

 

I saw on your 27 Chickens post where you said you assumed the dealer had filled the tank. Not necessarily a good assumption. Since most Priuses will travel 100 miles or more before the first bar on the Guess Gauge bites the dust, you'll never know.

The FIRST thing I do now after I drive a new car off the lot is find a gas station and fill up, even if the gauge reads "full". Even though I have to smile weakly when I hand the attendant a $5 (knowing he/she may have to give me back $4).

I'd just start keeping my data when I do my own first fillup. Or, as you said, fudge whatever-it-is to about 42 MPG. I'm surprised you've driven it as far as you have; you must really wanna nudge it over 40.