Break in period: First thing to know if you are driving your Prius off the lot new, there is a break in period. You won’t see your best mileage for a full six months or 10k miles. Initially, you will get 10-15% improvement in fuel economy after the new car smell has drifted away.
Cold starts are mpg killers. The Prius get the worst mileage in the first five to ten minutes of driving. Let the Prius sit for two minutes before you begin driving and, if you can help it, drive after the day has warmed up.
Tire Pressure: A quick tip from drivers getting the highest mileage: use the maximum tire pressure on the sidewalls (not the recommended by manufacturer amount.) Pull your Prius into a Toyota dealer and they will be able to add air to your tires. Maintain this for the best mileage.
Gliding: The most important factor in minimizing your mpg is your ability to take your foot off the accelerator absolutely as soon as you know that you’ll need to slow down or stop–and getting into “glide” mode. Also while traveling at a more constant speed, remove foot from accelerator. Then, ever so slightly, re-apply pressure. This works best under 40 mph.
Accelerate slowly especially from a standstill. When accelerating above 20mpg, slightly lift your foot off the accelerator (but not all the way.) Then reapply your foot gently.Try your best to stay in that glide zone (pictured above).
More gliding techniques: For Prius drivers, the way you slow down and brake is much more important than acceleration techniques–and the goal is to “break glide” (description below) at every opportunity, regardless of the traffic conditions.
The main idea is to control the amount of braking that is used to regenerate energy to the batteries. (regenerative braking is essential for keeping energy in the batteries, but a little bit goes a long way. Avoiding overuse of regenerative braking will prevent you from slowing down more quickly than necessary. Extending your glides and coasts is a key to maximizing mileage.)
Cruise Control: If it all possible, set cruise at 55mph. For every mph over 50 you lose approximately 1 mpg. So slowing down from 75 to 70 mph will save you 5 mpg. 55mph may bring you 60-65 mpg for entire tanks. on flat land, cruise control is a more efficient driver than you are; use it when you can. Cruise control is not nearly as good in hilly terrain.
Learn to use momentum and gravity: take your foot off the gas going downhill and let the car be carried rather than powered. this is when you may not want to use cruise control: learn to use momentum and gravity. let the car slow a bit as you crest the tip of a rise, then let gravity speed you up on the downhill instead of the engine.
On air conditioning: use it instead of sweating, but do not ever use the max setting. Also, experiment with the windows down. Some hyper-milers say they have better luck with rolling windows down than using air conditioning regardless of speed.
Idle vs. shutdown: Place the Prius into park but don’t shut it down if you are to remain stationary for no more than ten minutes. Turn off the heating, cooling, lights, and other electric accessories. Push the ‘park’ button. The goal is to avoid shutting down and restarting, at which time the Prius will run through a start-up cycle that uses gas.
3 Driving Modes: With the 2010 redesign the Prius added 3 driving modes: EV, Eco, and Power. Your goal is to utilize these modes fully to improve your fuel economy. I recommend driving in Eco mode 95% of the time. It will make the gas pedal less sensitive and turn the A/C down if you have it on MAX. Stay in Eco whether you are driving in town or on the freeway. Power mode is great for merging onto the freeway or passing a big semi (or racing your Prius!) Use this mode sparingly because although it has some serious UMPH to it, it will eat away your fuel economy. Lastly EV mode is to be used under 25mph without too much throttle manipulation to run the car off the electric motor only; you must have ample charge to use this mode.
Additional tips: Speed is your enemy. Pick your route based on speed limits of 30-45 mph. Most Prius drivers report a steady ‘sweet’ spot 40-45mph, allowing you an opportunity to coast or glide.
Avoid jack rabbit starts altogether. This will certainly be a learning curve but accelerating slowly will help your fuel economy hugely just on its own.
Main Points Review:
Learn to use momentum and gravity
Utilize 3 driving modes
Master the art of ‘gliding’