Really annoying when trying to hypermile

You do realize that the next time you start your car, it will try and charge the batteries while the motor is cold and in efficient?


iPhone ?

 

Mine does everytime regardless...

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Right, it seems to me that some hypermilers are doing nothing more than trying to earn "bragging rights" by starting off a short trip with a fully charged battery, returning with a relatively depleted one, and reporting their MPG for that trip. I guess it's kind of a fun game that I might be tempted to join, but in the end I think it is really counter-productive for the exact reason you mention.

 

Just let the car do it's thing. It's smarter than the average driver when it comes to efficiency and the long term results will be the same. That way you also won't be distracted, obstruct traffic and piss off everyone else.

 

If I park my car with a full battery (SOC 75 - 80%) when I turn it on, it sits and warms up without sending any power to the pack which to me seems like a waste of fuel. I prefer to make sure my battery is depleted to about 50% when I park so that when my car warms up the engine, it's actually sending power to the pack that I can use to drive away, not just burning gas while warming up.

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That's a fair point. I guess the best strategy might be to try to manage our battery's SOC when parking based on weather conditions. If it is likely temperatures will be on the cold side the next time the car is started, perhaps nothing is lost by leaving the car's battery with a relatively low SOC, since the ICE will need to spend more time warming up and might as well charge the battery while doing so, that is presuming the warm-up cycle will not be extended by the need to bring the battery up from a low SOC. As has already been discussed in another thread, it would also be preferable to leave the battery with a low SOC when parking at the top of a hill, if it were known that descending down the hill would provide more regenerative energy than is needed to bring the battery up to a full SOC.

 

I don't try too hard to keep it battery-only especially considering it'll run the charge down quite fast. I do look for opportune times though: starting off on a slight downhill grade you can sometimes get up to speed completely on the battery. Or if there's a red light ahead, or you're coasting to a slowdown or curve: get off the gas asap, let the engine shut down and then coast up to the slowdown, using the battery a little if needed. Aim to use the brakes as little as possible; use up your momentum.

 

Hopefully you've read up on "Pulse & Glide" driving technique... That's the best way to improve MPG... Also to get max MPG you have to use both engine and battery pack together. Trying to force battery use, especially in your last miles home lowers your MPG because then you waste gas because the car has to restore battery pack charge next time you drive when engine is cold and inefficient.

Or if you get a pack charger from hybrid automotive you could charge your pack up when you get home by plugging it in... Also hybrid assistant phone app has some tools in it that will help guide you to maximize MPG. You'll need to buy a bluetooth device to connect your phone and car: priusapp.com/obd

But the #1 way to boost MPG is to keep as high as tire pressure as you feel comfortable with...

 

not that i can think of. you'd be better served to do your hyper miling during normal back road driving.

 

Have you, or anyone else, done any measurements to see if anything is saved or gained by this?

You mustn't assume that 'idling' with battery charging takes no more fuel than bare 'idling' without such charging. Charging from a spinning a generator is never free, it requires extra torque and power from some prime mover. For a motor, that requires extra fuel compared to idling unloaded.

When refilling the Prius traction battery, this extra fuel must be balanced against whatever savings happened while depleting the battery previously. Considering that this depletion / recharge process means laundering the energy through additional lossy conversion steps, it is not at all obvious that this balance will turn out to be positive or even neutral.

 

I'm about ready to throw something!! Stop making it all complicated, and just drive the damn car! Leave it in regular D mode, and don't mess with it. I don't know about the earlier generations of Prius, but when I drive my car normally the gas mileage is actually better! The heck with all that silly "hypermiling" stuff! SHEESH.

People are getting 45-55 mpg, and that's not good enough??? Buy a bicycle (and get some exercise. )

EDIT: Nothing personal against the OP. Maybe the Gen2 and 3 need to be driven differently? But I sure see a lot of earlier Gens blowing by me doing about 85 on the freeway! Just drive it, and have some fun! I'm always in PWR mode.

 

There's your fuel waster right there. Start it and go. The system will use the battery to reduce engine load while it warms up, so as they say, just drive it. This car is seriously smart.

 

Yes, but a Prius is a thinking person's car and many new owners, at least at first, tend to over think it... Myself included in the first few months, from installing the stealth mode wires to re-activate electric motor only option like on non US cars, seeing what use driving in B mode is, trying to keep charge bars in green no matter how much gas I waste...

All these things are quite common to try at first... Then once you think it thru it's not something you again do.

 

Note that he has a plug-in model, so that figure is not comparable to my and your non-plug-ins.

If you get that Prime you thought about in your next post, you can easily beat him. That is, unless you put the roof rack and bike on, that changes the picture significantly.

 

As @fuzzy1 said, it's a plug in. And a Prime leaves this thing in the dust for gas mileage. Usually, in hybrid mode I get 55-65 mpg. Last weekend, we did a road trip that was mostly interstate. 90 miles + each way starting with a full battery. Got 60 mpg going out and 61 mpg coming home. Interstate driving was about 55 mpg at 70 mph.

If not for road trips, I'd probably be averaging about 110-130 mpg.

 

I personally think there's one major factor concerning my gas mileage. My lead foot!