How much should I keep in the battery to get best fuel economy?

It seems to me that it doesn't really matter, unless you get the batt full and still are going down hill or have to stop and end up wasteing the regeneration of breaking. it may depend on the type of driving you do. on hwy it may make a difference if the batt gets to low. but in town driving 25-35 speed limits I am getting very good mpg. today I drove 40 miles with 88.? mpg on the display. usually I drive short trips and this kills the mpg. but this tank has 420 miles and average is 64.6 on the display. I am using 92 octane e10 and the mpg seems better than 87 octane e10, most people say the higher octane is a waste of money, but it sure seems to work better in my prius c with in town driving. On the hwy it doesn't seem to help but I am only on my second tank of preimium so time will tell.

 

you'll get your best mpg's by using the engine as much as possible, and the battery as little as possible. have you heard of pulse and glide?

 

no, it's using the ice to get up above your desired speed, (pulse) then holding the throttle so your not powering the car or charging the battery. (glide) rinse and repeat.

 

that's where you want to be, it's a minuscule amount of electricity.

 

Recharging the battery (especially at 2 bars) uses extra energy from the engine. The recharging process also has a bigger hit on your trip fuel economy if you are recharging at higher speeds.

Staying "a little above regen" (as highroller said) uses low current. This is also what I tend to do.

Using "a lot above regen" on all-electric uses very high current and is way less efficient since the battery drains faster... but this also implies more energy spent recharging during the trip.

 

Well THAT statement is grossly misleading.
If it were true, why HAVE a battery at all.

It is actually best to "glide" while not using either means of propulsion......but that gets tedious fast.

For the average driver........just keep a light touch on the throttle and let the car do the rest.

 

Not sure it matters. I pulse up to just over speed limit and let off, the car swithes the ICE off, I then pull into neutral. If the road is flat or downhill you can coast for a long time without slowing down much. after you slow or someone is comming up behind slip back into D and accelerate up to just over speed limit and shift back into N and this gives very good mpg in town I have had several times with 20-45 miles showing 80 plus mpg. I am MPG OCD and try to get every mile I can without making other drivers angry. where I drive there are small hills and I try to charge going up those hills as much as I can and coast on the downhill parts.

ps I am not sure but think this only works if speed is under 40 mph, otherwise the ICE keeps running.

 

Anyone who deliberately puts a car in neutral while moving is a couple of sandwiches short of a picnic.
In a split-second emergency (like a deer jumping into your path), drivers can use any combination of braking, steering and accelerating to try to avoid a collision. To deliberately disable one of these beggar's belief; to regain full control also requires steering one-handed. This is while the emergency situation is rushing at you at maybe 100 feet / sec.
I might add that in some jurisdictions such actions are illegal (read dangerous driving), and are likely to result in loss of your driving licence. Your insurance company wouldn't pay out on your claim either.

GT-I9300 ?

 

one always must be cautious when driving, you should know your limitations. haven't got in an accident in over 20 years. not to say I couldn't get into one, however I believe I will survive coasting at in town speeds as others are speeding away.