[Edward]

I have an ‘05 Prius. I have been driving it mainly in a rural
area on highways. I get between 49 to 53 mpg. Great!
Recently I spent almost 2 weeks in a city (Madison, WI). The
mileage fell instantly to 40 mpg and stayed there all the time
I drove in a heavily trafficked urban environment. I thought that
this car was supposed to have the highest mileage in cities
and less on highways. Am I doing something in town that
I shouldn’t?

 

[coloradospringsprius]

Your experience is pretty normal. The EPA's definition of "city" is somewhat different than what most of us envision when we hear the word:

http://www.fueleconomy.gov/feg/fe_test_schedules.shtml

... and there is evidence that the Prius, for some reason, gets especially unrealistic city results.

Like all cars, the Prius' mileage drops in authentic stop-and-go driving. On the plus side, it drops less - on a percentage basis - than it does with a conventional car.

There are a few tricks to improving city mileage, such as looking ahead to avoid unnecessary acceleration and braking, and going into gliding mode when possible (basically coasting, but without taking the car out of D). It takes some looking at the energy screen to get the feel of gliding - it occurs when there are no lines going to or from anything on the energy screen - but it can increase your in-town mileage significantly. And of course it only works on slightly downhill sections of road.

FWIW, my experience is basically identical to yours: We're getting 52 mpg lifetime, but with our mileage almost backwards from the EPA numbers - about 58 mpg on the highway and about 44 in town.

 

[kirby]

I too get better highway than city, but I get very good mileage in what I will call light urban traffic. The key to doing well in the city is to anticipate and try to not use the brake - takes practice but can be done. AC will kill you more in the city even in a non-classic prius.

 

[evander]

I was listening to a car expert on "talk radio" this morning. A woman called in asking about a hybrid and would she do better with it on her 80 mile each way highway commutes each day. This expert(??), apparently not informed on hybrids, repeated the mantra that city driving gives better mileage than highway. He apparently hadn't talked to a hybrid owner. Thus, he discouraged her from purchasing one. We "experts" who own a Prius, soon realize that highway driving usually gives better mileage than short commutes, stop signs, etc. I felt like yelling over the radio to her, "Don't listen to him!"

 

[Rmarchena]

It is normal...

Like somebory said in one response to your post:

"Your experience is pretty normal. The EPA's definition of "city" is somewhat different than what most of us envision when we hear the word."

That means:
Your Prius is going to perform INCONSISTENLY in a real city all the times.
Please, get use to it and start loving your car just like that, or start driving in the unsafe Prius style.

 

[Ray Moore]

I get much better mileage in the city. There is some technique required but my city mileage is usually in the 70s unless I run the AC while not going anywhere.

 

[evander]

70's? How can one maintain that when one must accelerate so often in the city--even with coasting and feathering?

 

[Ray Moore]

I just watch ahead and seriously reduce the number of times I come to a stop. It's just not that hard if you are into that sort of thing. Limit your braking. I probably couldn't do it in say downtown Chicago, but driving around Austin, it's not that difficult, especially on roads where I am familiar with the lights and traffic patterns.

 

[coloradospringsprius]

I could imagine getting Ray's mileage, or close to it, in certain parts of Denver, where the traffic engineers' goal has been to keep traffic moving as smoothly as possible. It would be impossible in most sections of Colorado Springs, where the stoplights have been intentionally timed to break up traffic flow. (I'm not making this up - this is a conscious engineering decision that is believed to minimize speeding. I'll see if I can find the rationale when I go back to work week after next.)

 

[coloradospringsprius]

Re: It is normal...

Like somebory said in one response to your post:

"Your experience is pretty normal. The EPA's definition of "city" is somewhat different than what most of us envision when we hear the word."

That means:
Your Prius is going to perform INCONSISTENLY in a real city all the times.
Please, get use to it and start loving your car just like that, or start driving in the unsafe Prius style.

As the "somebory" who was quoted, I have to say that's not what I meant at all. The Prius performs VERY consistently in a real city. Mileage goes down when you have short trips or do a lot of stop-and-start driving. Mileage goes up when you have longer, steadier trips. Mileage goes down if you accelerate hard and brake hard, paying little attention to the traffic environment around you. Mileage goes up if you drive the car as it was designed to be driven, which, btw, is not at all unsafe. Being more aware of the conditions around you almost always makes you safer - the Prius also pays you for your attentiveness.

 

[BIF]

I get better gas mileage on city streets between 40 and 45 MPH, as long as I hit all green lights.

During rush hour, it's often more fuel-efficient to drive on the freeway rather than hit 6 or 7 traffic lights and deal with that aggravating and dumb "accordion effect" (aka: "inchworm effect") of traffic.

When the inchworm gets longer than 5 or 6 cars deep, then the entire inchworm never makes it through a green light, adding to everybody's conscious and sub-conscious stress levels.

In my opinion, this is the major contributing cause to our overconsumption of oil, as well as to the accident and death rates on the roads.

On a per-person basis, busses have a lower "inchworm" effect, and trains have virtually none of this phenomenon. But busses and trains have a higher exposure to terrorist attacks and other criminal activity.

We desperately need to figure out ways to move ever greater numbers of people with ever fewer barrels of oil.

 

[MikeFromEastCoast]

I don't think starting and stopping is too bad on the MPG if you don't stop too quickly and force it to use the brake pads instead of recovering that energy. So far I have been averaging about 53mpg on my 55 mile daily commute. It gets better MPG in heavy stop-and-go traffic than when I can go as fast as I want (*doesn't mention actual speed driven*). The best I've gotten so far on a tank has been 58MPG. I think the worst has been around 45MPG. I expect the MPG will go down somewhat this winter because it will have to use more fuel to stay at operating temperature.

The faster you go the more enery is lost from air resistance. If I remember my physics correctly, the air resistance is proportional to the square of the speed (or is it the cube?). I think the 50 MPG breakpoint for me is somewhere around 65mph. Above that speed MPG would be lower, below it, somewhat higher. Also, it gets worse MPG on short trips (5-10 minutes) where I presume much of the energy is spent just warming up the ICE.

I don't try to go slower than I normally would to conserve gas because I don't want to give other people the false impression that hybrids can't go as fast as regular cars. I go in the fast lane at the speed of that traffic, but my reaction to traffic jams is different with the prius than it used to be with my former car. It's like ' what kind of MPG will I get now' instead of ' look at all this traffic'

 

[DanMan32]

I agree, stop/start shouldn't be a problem, as long as the "stop" is not so long that you drain the battery. Running AC will reduce the available "stop" time and remain optimal.
Also, the other criteria, is how fast are you accelerating to? Accelerating to 30MPH frequently isn't so bad, but accelerating to 55 frequently is.
Most of the time, when we stop/start from/to the 30's, we are doing short trips too.

EPA city is like 20 minutes at an average of 28 if memory serves me.