Hybrid Fuel Economy

[Leighcm]

I'm on a Toyota mailing list and received this today...thought it was interesting, and may help everyone get a little better mileage:

Toyota's recommendations for getting the most out of your mileage:

Keep tire pressure at recommended levels; under-inflated tires use more gas.

Avoid driving at speeds that are higher than necessary, especially on the highway.

Avoid jackrabbit starts and, when possible, avoid sudden stops.

Don't carry items in the car that you don't need; additional weight means lower mileage.

Use air conditioning in moderation.

The mileage tips below come straight from hybrid drivers, and contribute to facilitating the sharing of ideas in the hybrid community:

One hybrid owner offers an imaginative analogy for getting the "Zen" of thrifty hybrid driving:

"Imagine pedaling a bicycle with your own leg power. You cruise as much as possible. No need to go full throttle before a stop. Glide to a stop instead. Don't race to cruising speed. Take it easy on the engine just as you would on your legs."

Another hybrid owner counters this approach, suggesting that rapid acceleration to speed followed by cruising is actually more efficient, though counterintuitive.

Perhaps the best thing is to try both and see for yourself.

Adding to the old debate over driving with the air conditioning on or the windows open, one Prius owner suggests that with a Prius, keeping the windows open is more economical. The rationale: Battery drain from air conditioning uses more gasoline than aerodynamic drag caused by open windows.

Remember that for every mph above 55 in a Prius, you could lose up to one mpg, mostly due to atmospheric drag -- even with its advanced aerodynamic body.

Common-sense maintenance also leads to good mileage. Change oil on the maintenance schedule and don't use heavier oil than is recommended in the owner's manual. Heavier oil can mean mpg-robbing drag on the engine. Inspect your air filter and replace it on the maintenance schedule or as needed. A choking engine uses more gas.

Techniques of a mileage champion

Some Prius owners keep pushing the hybrid mileage envelope to the max. Five of these "hypermileage" enthusiasts recently teamed up and set a record of nearly 110 mpg in a marathon economy run.

Hypermileage techniques are not for everyday driving. They have to be practiced in controlled conditions and then become "second nature" because of the attention that must be paid to the dashboard display at first. Here is a description of how Dan Kroushl, one of the marathoners, adapts hypermileage techniques to daily driving in his Prius:

"On the highway, I just set cruise control to 55 mph and go. In city driving, during acceleration or maintaining speed uphill, I use the deadband technique. This means no flow to or from the battery while accelerating. I glide (no flow at all, engine is stopped) during mild downhill stretches. I apply the brakes (regenerative) on steeper downhill stretches to keep my speed below 42 mph.

"I do this because the motor-generators (MGs) reach their maximum rpm at about 42 mph, which forces the engine to run to prevent damage to the MGs. So at speeds above 42, the engine must run, which creates added friction. This must be compensated for to maintain speed, causing a reduction in fuel economy.

"When coming to a stop I coast (foot off the accelerator) until the stop. While braking and coasting, a small amount of energy is regenerated to maintain the battery level. I use this technique on my daily commute which is 50% highway at 55 mph and 50% city at 35 mph. Depending on environmental variables, during the summer my fuel economy ranges from 67 to 72 mpg."

Try some of these techniques and see how your mileage improves.

[fidgits]

Thats some good advice there.

[stevelaw]

Well, today marks the start of an experiment. I have always preferred to temper my oil with the climate. I always use good oil, 10W40 when it gets very hot, like here in Georgia, and 10W30 in the winter. I have discovered about 1 MPG mileage gain with Mobil Drive Clean 7500 10W30. Today I put Mobil Drive Clean 7500

5W30 in. I'll be tracking mileage closely with this oil to see if I have any additional mileage gains.

And don't forget that K&N air filter helps too.

[lexus]

nice advice will try on my prius

[gaspricestoohighforme]

Hi, had my old 2002 Prius for 4 weeks now. Noticing that the energy management computer is rather, uh, intellectually challenged and narrow minded. It does not adapt. Toyota would have done well to have installed software that adapts to different driving conditions. Correct me if I'm wrong but it Appears that it is only rigidly set up for "city" and only city driving as far as utilizing the battery capacity most efficiently. For example when I drive to work it is on rural highways, stopping then acceleratiing again to 55mph during which time the battery is anal-retentively kept at a full charge and never utilized to help the car up to speed beyond maybe 15mph. Seems to me there's enough unused capacity in that battery to assist the car all the way to 55mph that is never tapped. Maybe there's something I'm missing? Is the electric motor not capable of assisting beyond a certain point or is the software simply not up to it??? Is there a software upgrade possible?

[Steve]

i dont own one but i have had a good lengthy drive of 2 hybrids, from what i can see the electric motor assists the engine. Going by the graphic display that is. I dont think it stops at 15mph, it would be a lot faster before it stops working altogether. Its is supposed to assist the engine too.