Do not be scared of using that charge button.

[Daboyz]

Hi Trex, very clear and very interesting.

Despite being an engineer, I have never used the Charge mode assuming it to be inefficient.

Let’s discuss an example journey: 20 miles city driving (EV or series mode) followed by 100 miles motorway (parallel mode) followed by a further 20 miles city driving. I have always driven this by selecting EV in first city stretch, Save on motorway, Normal mode in final city stretch where the car does its own thing between EV and Series modes.

What I think you are saying is that on the same journey I might use less petrol if I used EV mode on first city section, then a mix of Charge and Save on the motorway so that I put back sufficiient Charge to complete the final city section in EV mode.

I shall certainly try it out.

Hi Chris,

Yes I use the Charge button to pump up the drive battery in parallel mode before I get to cities or towns to avoid series mode.

It gives me my best measurable fuel economy savings. That plus not travelling everywhere with a full drive battery.

Regards Trex.

[dogman12]

Here's a challenging problem:

Gasoline is $3.50 US per US gallon. Electricity is $.10 per kwh. (Both true for me right now)

Under what conditions of load, speed, and distance does "Charge" result in $.10/kwh in the battery?

Or: on 100% EV assume @ 3 Mi/Kwh, for @ $.034 per mile. On 100% ICE assume 26 mpg for @ $.135 per mile.

What is the $/mile when Charging, vs other modes?

[ThudnBlundr]

You're forgetting that the car runs in what is effectively Charge mode when the battery is empty or you press Save. Your car charges for a while, then switches to EV till the range drops and charging starts again. It is immaterial how much Charge costs; the default action for the car is to use it for well over 50% of the time once the battery is used!

If you can do a whole journey on EV, Charge is obviously not worthwhile. But if the ICE needs to run, using Charge and/or Save effectively can reduce consumption slightly.

[MH8173]

If you can do a whole journey on EV, Charge is obviously not worthwhile. But if the ICE needs to run, using Charge and/or Save effectively can reduce consumption slightly.

Spot on!

I think this is exactly what OP means: "Do not be scared of using that charge button".

If it's gonna run anyway, you can keep it running for longer.. sometimes It can pay off later when you can do pure EV in town etc, very much depending on the situation. Standing still on a parking lot or running around town charging likely won't pay off.

The car does It's best to keep fuel consumption low right now, given the current parameters. It does not know what's coming ahead.. however you do.

[Trex]

If you can do a whole journey on EV, Charge is obviously not worthwhile. But if the ICE needs to run, using Charge and/or Save effectively can reduce consumption slightly.

Spot on!

I think this is exactly what OP means: "Do not be scared of using that charge button".

If it's gonna run anyway, you can keep it running for longer.. sometimes It can pay off later when you can do pure EV in town etc, very much depending on the situation. Standing still on a parking lot or running around town charging likely won't pay off.

The car does It's best to keep fuel consumption low right now, given the current parameters. It does not know what's coming ahead.. however you do.

When it is all said and done this graph and explanation from the designers of the PHEV which I posted previously in this thread to me says it all. Try and avoid slow speed Series mode when running the petrol motor ie try and run the petrol motor in Parallel mode if you can. Using Charge mode while running in Parallel mode can help on some trips out of EV range so you can avoid slow speed Series mode later when you come to towns or cities etc.




Image from Mitsubishi Motors

Also shows travelling above approx 120 kph speed is not considered the best for efficiency.

[Fjpod]

Just read this whole thread trying to get a grip on the best way to reduce gasoline consumption on long trips. It's been over a year since anyone contributed. Don't mean to criticize here guys, but most people are all over the place with anecdotal evidence... And I guess I will add to it...

I tried using Charge recently on a long trip, my instantaneous mpg went down. It's hard to imagine how this is better for reducing gasoline consumption. Listening to everyone giving their experiences... Uphill .. downhill... How is one supposed to enjoy the drive?

It would seem to me the only time it pays to use Charge would be near the end of a long highway trip to ensure you have enough drive battery to get through whatever slow town driving you need to get to your destination.
... And maybe near top speed, if the ice is not laboring heavily, you might try to siphon off some revolutions to send to the battery.

Fwiw.

[ThudnBlundr]

Just read this whole thread trying to get a grip on the best way to reduce gasoline consumption on long trips. It's been over a year since anyone contributed. Don't mean to criticize here guys, but most people are all over the place with anecdotal evidence... And I guess I will add to it...

I tried using Charge recently on a long trip, my instantaneous mpg went down. It's hard to imagine how this is better for reducing gasoline consumption. Listening to everyone giving their experiences... Uphill .. downhill... How is one supposed to enjoy the drive?

It would seem to me the only time it pays to use Charge would be near the end of a long highway trip to ensure you have enough drive battery to get through whatever slow town driving you need to get to your destination.
... And maybe near top speed, if the ice is not laboring heavily, you might try to siphon off some revolutions to send to the battery.

Fwiw.

You're totally missing the point of how the PHEV works - it needs a certain amount of energy to get from A to B and it has to get that energy from the ICE once the battery is empty. On any journey that would empty the battery, the PHEV will run in what is effectively Charge mode to top up the battery until the range has increases a mile or so and then run in EV till the range has dropped down. With Save pressed, it does the same except around the higher EV range. So it has to run in Charge far more than 50% of the time whatever you do, and it cycles through this hysteresis loop until the end of the journey regardless of how or where you're driving. So saying that pressing Charge increases fuel consumption is meaningless. Of course it increases consumption, but how is the PHEV to get energy to move otherwise?

What you can do is influence when the PHEV is using EV or charging from the ICE. So running Charge for longer than the usual 1-mile increase in range will allow you to use EV for longer. So you can choose to run EV in town and Charge on faster roads, which is environmentally more friendly and some believe may be more fuel-efficient. But you can't alter the fact that the PHEV needs to run the ICE whatever you do.

[twosout]

I think any difference between letting the 'car brains' do the work and trying to manage it myself will be marginal. If I could manage it well, it ought to be better because I know the nature of what is ahead and the car does not. Has anyone got any credible evidence that taking control yourself is worth it?

The car will charge in Parallel or Series mode. I think that charging in Parallel would be more efficient than in Series because the brains can run the engine at peak performance all the time whereas the engine speed is fixed to the road speed in Series mode and charging will 'steal' performance from the drive. In Parallel, the brains can get the engine to spin at any speed and siphon off what is not needed for propulsion.

[ThudnBlundr]

I think any difference between letting the 'car brains' do the work and trying to manage it myself will be marginal. If I could manage it well, it ought to be better because I know the nature of what is ahead and the car does not. Has anyone got any credible evidence that taking control yourself is worth it?

The car will charge in Parallel or Series mode. I think that charging in Parallel would be more efficient than in Series because the brains can run the engine at peak performance all the time whereas the engine speed is fixed to the road speed in Series mode and charging will 'steal' performance from the drive. In Parallel, the brains can get the engine to spin at any speed and siphon off what is not needed for propulsion.

I'm sure you're right - left to its own devices the car simply runs through the hysteresis loop, so prior knowledge *should* help.

It seems to be generally accepted that it is better to Charge in parallel and use EV when it would be Series, though I've not actually seen any evidence either way. You seem to have them the wrong way round, as the engine speed is fixed to road speed in Parallel mode, when the engine is powering the wheels directly via the single fixed gear. This means that it can run the engine at the peak efficiency for that rpm; most of the power goes to propelling the car via an extremely efficient gear set and it sends only the 'spare' power to the battery. In Series you have the multiple losses of an ICE powering a generator which then charges the battery and powers the wheels through the electric motors.

[greendwarf]

And, of course, charging won't "steal" from the Drive - it is the other way round, as propulsion will always be the first call on the energy from the ICE, as dictated by your foot on the pedal.