I use charge mode for better fuel consumption.

[anko]

But I think we can all agree that serial mode charging is not as efficient as parallel mode charging otherwise ...

Hang on ... you say so, but is this really true?

Why would serial charing be less efficient that parallel charging? It is not so much the serial charging that is inefficient, compared to parallel charging. It is the electric driving on (previously) generated power that is inefficient, compared to parallel driving. Because, instead of sending mechanical power directly to the wheels it means:

- converting the mechanical power to electrical power with some loss
- optionally storing it in the battery with some loss and retrieving it from the battery later with some loss (charging followed by EV mode)
- sending the power to the motors
- converting it back to mechanical power with some loss

Due to these losses, EV driving on generated electrical power is less efficient then driving in parallel mode. But it is not something we have control over. Traffic circumstances dictate our speed most of the time. But does it matter when the electrical power used for driving in EV mode was generated? At speeds below 65 or above 65 km/h?

You could even argue if it was not better to use generated power as much as possible directly at the time it was generated (serial mode) instead of later (charging followed by EV mode). Two prevent charging / discharging losses.

 

[Trex]

Hi anko,

You wrote : I use and ELM327 WiFi as WiFi is what the iPhone needs. Works reasonably well, as long as I have a profile installed on my phone that prevents it from spontaneously connecting to the REMOTExxxxxx WiFi. Otherwise, it will have a hard time connecting or will loose the connection quite frequently. With the profile, it is alright

Thanks for that information. I will do a search on the ELM327 on prices here in Aus.

You wrote : Hang on ... you say so, but is this really true?

Ok I should have not have spoken for anyone else. Point taken. I should have said my Phev gets better fuel consumption by avoiding serial mode charging.

How do I know ? My fuel figures on the same trip that I have regularly done over the last 11 months using different techniques. Other people can try this technique (or not) and come to their own conclusions.


Regards Trex.

 

[Trex]

Hi anko,

You wrote :"Why would serial charing be less efficient that parallel charging? It is not so much the serial charging that is inefficient, compared to parallel driving. It is the electric driving on (previously) generated power that is inefficient, compared to parallel driving. Because, instead of sending mechanical power directly to the wheels it means:

- converting the mechanical power to electrical power with some loss
- optionally storing it in the battery with some loss and retrieving it from the battery later with some loss (charging followed by EV mode)
- sending the power to the motors
- converting it back to mechanical power with some loss

Due to these losses, EV driving on generated electrical power is less efficient then driving in parallel mode. But it is not something we have control over. Traffic circumstances dictate our speed most of the time. But does it matter when the electrical power used for driving in EV mode was generated? At speeds below 65 or above 65 km/h?"

I think I was misunderstood you when I first read what you wrote. Do you mean charging up the battery (like I do out on highway with charge button) around urban areas (with charge button) for later use it could be just as efficient? Would that include while stopped at traffic lights etc? Perhaps it could be that if you were stuck in a city town etc, for an extended period and below the speed of parallel mode it may be just as efficient a technique. I have not tested this.

I hope I am understanding what you mean.

Regards Trex.

 

[anko]

Sorry, I meant to write "why would serial charging be less efficient then serial charging". But I think you got that

For the rest, I think I need to think it over a bit more. Complex stuff .... :mrgreen:

 

[anko]

Next occasion where I can do 100 km/h on cc, I will check.

Didn't manage 100 km/h but did manage 90 and 80. At 90 I got 10.9 both on the scanner and in the dashboard. At 80 I got 10.3.

The fact that I had just a little bit more consumption in the past at 100 km/h (11,1) is IMHO related to the fact that the faster you drive, the less you will charge. At 130 km/h I thinpk there is hardly any charging at all.

Did some more tests:

100 km/h - 11,0 l/100 km
110 km/h - 11,3 l/100 km
120 km/h - 11,5 l/100 km

Speeds are GPS. Fuel consumptions taken from MMCS, by resetting the trip computer as soon as the engine starts.

 

[Trex]

Next occasion where I can do 100 km/h on cc, I will check.

Didn't manage 100 km/h but did manage 90 and 80. At 90 I got 10.9 both on the scanner and in the dashboard. At 80 I got 10.3.

The fact that I had just a little bit more consumption in the past at 100 km/h (11,1) is IMHO related to the fact that the faster you drive, the less you will charge. At 130 km/h I thinpk there is hardly any charging at all.

Did some more tests:

100 km/h - 11,0 l/100 km
110 km/h - 11,3 l/100 km
120 km/h - 11,5 l/100 km

Speeds are GPS. Fuel consumptions taken from MMCS, by resetting the trip computer as soon as the engine starts.

Ok got the Phev off my wife, found a good flat section on freeway (did test both directions this time and averaged result)and using same criterion (MMCS and GPS and empty hv battery) as you anko and I get,

80 km/h - 10.2lts/100ks I could not test this reading properly for fear of holding up traffic ie did not test both directions.
90 km/h - 10.2lts/100ks
100 km/h - 10.4lts/100ks
110 km/h - 10.6lts/100ks
Could not do 120 km/h without fear of getting fined by police.

So my 110 km/h is worse than what I had previously wrote ie 10lts/100ks (at 110kph GPS) but I did test it on a flatter section and both directions this time.

Like I said before I am using Premium fuel which might be affecting the differences in our result. :?:

Regards Trex.

 

[Trex]

Hi again anko,

What did surprise me on driving back from freeway in the above test in the 60kph zones here (serial mode), and resetting MMCS like in the above test, I was seeing 9 - 9.5lts/100ks and even a 9.8lts/100ks on what I considered flat sections of the road. This would obviously come down over time when the petrol motor shuts down and it goes into ev mode but I did not expect it to be that high.

It would appear parallel mode is more efficent :lol:

Regards Trex.

 

[anko]

Hi again anko,

What did surprise me on driving back from freeway in the above test in the 60kph zones here (serial mode), and resetting MMCS like in the above test, I was seeing 9 - 9.5lts/100ks and even a 9.8lts/100ks on what I considered flat sections of the road. This would obviously come down over time when the petrol motor shuts down and it goes into ev mode but I did not expect it to be that high.

It would appear parallel mode is more efficent :lol:

Regards Trex.

I also think parallel mode is more efficient. Although it has to doc penates for increased air resistance.

But the number you give is (I beg your pardon) meaningless, when comparing efficiency in serial mode and parallel mode. It only makes sense to compare the average consumption after so many kms.

Let's assume that so where between 2 and 3 liters / 100 km ar used for charinging. That brings consumption associated with driving back to 7 - 8 liters / 100 km. but more important, the extra consumption gives you a certain amount of kWh in a certain amount of time. That amount of kWh gives you a certain amount of EV kms later on. You get more kms @ 60 km/h than you will get @ 100 km/h. This means longer periods of EV drive between the periods of serial drive. Or shorter periods of EV drive.

So, the difference in instanteneous fuel consumption will be rather limited where the difference in average consumption will be more substantial.

My guess.

 

[Aitch]

I've tried to follow this thread through and only managed to add to my confusion! Can I ask for opinions on my thoughts on the best way to drive the following journey:
From my home to my rented digs for work is 165miles door to door. Rented place to work return commute is 16miles. The majority of the 165 is A road / dual carriageway. I had planned to drive this section starting with a full charge, so EV mode until I deplete the battery then serial mode engine/motor, I was going to aim at maintaining 55mph or as close to and use the regen to add as much as possible, the journey is flat (Norfolk to Warwick). The commute I should be able to complete in EV mode only, I can't charge at work but can at my digs. Any thoughts, hints or tips as to how I could do it better. I get the phev this coming Monday and I'm looking fwd to trying to max out on the potential!

 

[Trex]

Hi again anko,

What did surprise me on driving back from freeway in the above test in the 60kph zones here (serial mode), and resetting MMCS like in the above test, I was seeing 9 - 9.5lts/100ks and even a 9.8lts/100ks on what I considered flat sections of the road. This would obviously come down over time when the petrol motor shuts down and it goes into ev mode but I did not expect it to be that high.

It would appear parallel mode is more efficent :lol:

Regards Trex.

I also think parallel mode is more efficient. Although it has to doc penates for increased air resistance.

But the number you give is (I beg your pardon) meaningless, when comparing efficiency in serial mode and parallel mode. It only makes sense to compare the average consumption after so many kms.

Let's assume that so where between 2 and 3 liters / 100 km ar used for charinging. That brings consumption associated with driving back to 7 - 8 liters / 100 km. but more important, the extra consumption gives you a certain amount of kWh in a certain amount of time. That amount of kWh gives you a certain amount of EV kms later on. You get more kms @ 60 km/h than you will get @ 100 km/h. This means longer periods of EV drive between the periods of serial drive. Or shorter periods of EV drive.

So, the difference in instanteneous fuel consumption will be rather limited where the difference in average consumption will be more substantial.

My guess.

I am sorry anko that was just a joke I was having when I said: "It would appear parallel mode is more efficent :lol: "
I know you cannot compare using those figures .

After comparing yours and my fuel consumption figures are you going to try Premium petrol?

Regards Trex.

 

[Trex]

I've tried to follow this thread through and only managed to add to my confusion! Can I ask for opinions on my thoughts on the best way to drive the following journey:
From my home to my rented digs for work is 165miles door to door. Rented place to work return commute is 16miles. The majority of the 165 is A road / dual carriageway. I had planned to drive this section starting with a full charge, so EV mode until I deplete the battery then serial mode engine/motor, I was going to aim at maintaining 55mph or as close to and use the regen to add as much as possible, the journey is flat (Norfolk to Warwick). The commute I should be able to complete in EV mode only, I can't charge at work but can at my digs. Any thoughts, hints or tips as to how I could do it better. I get the phev this coming Monday and I'm looking fwd to trying to max out on the potential!

Hi Aitch,

Basically this thread has been about how I get the best gains in low fuel consumption use by avoiding running the petrol motor in low speed areas. Here in Australia that is 60kph zones. On trips away I make sure I have enough charge in the drive battery to cover those slow speed areas. I do this by pressing the charge button on the freeway (100 - 110kph).

Regards Trex.

 

[anko]

@Trex, will try. Next time.