56.4 Mpg

[Quaker]

My best mileage so far has been 56.4 for 509 miles. I commute ~70 miles per day roundtrip and that week had a lot of stop-and-go traffic (where the hybrid really shines). Have had many tanks in the 52-53 range. Mileage declines quickly as average speed goes over 60-65 mph.

[Neicy]

Great job! What kind of weather are you doing that in?

[Paulbunning]

After 15,000 miles I have never had gas mileage below 52 and usually it is about 54.5 -- in all kinds of driving, from crossing mountain ranges on I-90 to fast commutes on I-5 to trundling rural highways. (I've had several complete gas tank fills at 60 MPG -- in the summer.) US News & World Report published my letter describing a trip from the coast to Big Sky, MT. and back, at 70 mph with four people in the car and the AC on -- we got 50 MPG. (The magazine had published an auto guide knocking the Prius and stating even an EPA expert was unable to do better than 46 MPG with the car... which is why I wrote my letter.) Lately my daughter has been driving the car to school (45 minutes each way, some on I-5) and even this new 16-year-old driver manages 52 MPG.

I think the main thing is to drive smoothly -- anticipating stops ahead, not speeding up to stop lights and then jamming on the brakes, etc. If you pay attention, the chance to coast comes surprisingly often -- particularly when you're heading down a hill at speed limit and you neither want to speed up nor slow down. That's when it's handy to lightly touch the gas pedal just enough to forestall regenerative braking (which saps speed quickly.) Using that particular trick probably adds at least 1 MPG to your overall average.

[fruzzetti]

sorry this is getting so wordy - i promise it'll pay off; if you want to improve your mileage you want to read the whole post.

you're exactly right on all counts. coasting with pedal and low-waste braking are the most important and easiest techniques to master.

as described, when you encounter a slight downgrade you can take advantage of the car's low drag coefficient by just applying enough brake pressure to coast (the car will not coast automatically -- it will decelerate and recharge the brakes); you can watch the run status screen to determine how much pressure you'll need and it becomes second nature.

the other is braking. predict when you'll need to slow down or stop and begin the braking process way early. if you're sensitive to the vehicle you'll be able to feel both in the brake pedal and in the deceleration pattern exactly when the brake system begins to work alongside the regenerative braking -- your goal should be to always apply LESS pedal pressure than that transition point while decelerating, so as much momentum as possible can be used for recharging the brakes.

third and also very importantly, when the car is stopped but in gear, you need to apply a greater brake force than you may be used to. remember, toyota programmed the car to behave like a typical automatic -- when the car is in drive it wants to creep forward, even with your foot on the brake. the sacrifice here is that when you use just barely enough pedal pressure to prevent the car from moving (watch the run status again), the car will waste energy fighting against you and trying to creep forward. you should press harder on the brake pedal once stopped, as this will switch off the creeping feature.

accelerating is another science entirely, and requires a greater deal of learning and attention. i'm not going to dedicate a bunch of energy to it here, but one of the principles that has worked for me is "accelerate gently until the engine kicks on, then hit it to get to your desired cruising speed as quickly as possible, then use cruise control or coast whenever possible." another is "just be patient and slow when going uphill."

~ dan ~

[djhnd]

I don't understand this thread: one person seems to be saying a light touch on the accelerator pedal when going downhill prevent the car from
going into regenerative braking, another seems to be saying that a light foot on brake pedal prevents it yielding best milage.

I've found, in my 450 miles of ownership (got it less than a week ago) that when going downhill I get 99.9 mpg current if I have light touch on accelerator pedal.

However I'm still only getting 51 mpg - but it is in the low 30s out, and I have the heat on all the time (get cold feet.)

I welcome links to suggested reading on here on impact of heating / AC on mpg and how best to correct for it.

[N3FOL]

Awesome mileage. I can't wait when summer comes... I hope to get over 50 mpg. From my last tank, I calculated 47.87 mpg driving in SE Pa.

[a priori]

Originally Posted by djhnd

I don't understand this thread: one person seems to be saying a light touch on the accelerator pedal when going downhill prevent the car from going into regenerative braking, another seems to be saying that a light foot on brake pedal prevents it yielding best milage.

I think you just missed the intervening statements. A light touch on the accelerator pedal (enough to prevent regen braking) will allow you to coast, thus saving energy. The light foot on the brake pedal at a stop light could allow the computer to think you intend to engage the car in drive. This mimics an automatic transmission, and it could use battery power, I suppose. At that speed (0), though, you are engaging the physical brake pads, and I don't know that you are wasting energy from the battery.

Originally Posted by djhnd

I welcome links to suggested reading on here on impact of heating / AC on mpg and how best to correct for it.

The best way to avoid the mpg hit is to avoid the use of A/C or heat. This is impractical (and something you won't do, anyway), so the next best option is to use it less and at a lower energy draw. By not using heat for the first several minutes (~5), you'll allow the engine's heat to be transferred to the coolant. This will increase efficiency (mpg performance) at a cost of slightly cooler toes. After that, you can engage the heat at one of the two lowest settings. Doing this, you'll avoid (or minimize) the problem of the engine continuing to run while you are at a stop. One of the biggest reasons for loosing mpgs in the winter is that the engine (ICE) runs more than in other seasons. It is running more not just to gain its own heat, but also to provide energy to heat the cabin.

Using the AUTO feature also can be a drain on energy (thus a lower mpg).

Two other ways to diminish the mpg "hit" in the winter: 1) Install an engine block heater (many links on this); and 2) Install insulation on the grill to prevent quick cooling at very low temps (many links on this, as well, but check out the Grill Blocking Summary Article in the Knowledge Base forum).

Hope this helps!

[N3FOL]

I love to use my A/C all the time in the summer. Will I be able to still get at least 45 mpg

[fruzzetti]

I love to use my A/C all the time in the summer. Will I be able to still get at least 45 mpg

Yes; 45mpg is not a lot to ask out of these cars in the summer. Also, remember the car runs better when it's warmer out (and it warms up in a shorter amount of time). If you practice driving it like a video game, you should easily and consistently get high scores in the low 50s.

~ dan ~

[hoop]

Originally Posted by N3FOL

I love to use my A/C all the time in the summer. Will I be able to still get at least 45 mpg

In south Texas I am happy to get 45. Thats about average for me. I have a touring model and the A/C is alway on in automatic set for about 73 deg. It gets very hot and humid here. Also I should tell you most of my miles are highway about 65 mph. My mileage is much greater when I'm in town but little of my driving is done there.