Fuel consumption in relation to Drive battery levels.

[Trex]

Hi folks,

This will be the last test I will do for awhile. I hope it helps everyone.

I picked the flattest area around here ( and it is very flat across the river valley here) on the dual lane freeway (in each direction) that runs past our small city. It is made up of approx. 12kms of 100kph zone and 10km of 110kph zone. I picked that stretch for its easy turn around at each end as well as being flat.

So the test consisted of driving in one direction then the other followed by a quick turnaround at each end. Traffic was light. I sat on 105kph . I used cruise control the whole time except at each end when I was turning around.

Now this is the same as I did the other night but more scientifically ie I ran both directions fully before taking measurements to allow for any wind or elevation changes. I have not, I repeat not done that before.

Here are the results.

Press save button straight at start with full battery. 15 bars showing (out 16 ) on MMCS when finished test. 7.8L/100k Petrol motor never stopped. B5 15kw

Press Save at 13 bars. 14 bars showing (out 16 ) on MMCS when finished test. 7.8L/100k Petrol motor never stopped. B5 25kw

Press Save at 11 bars. 12 bars showing (out 16 ) on MMCS when finished test. 7.4L/100k Petrol motor stopped a couple of times B5 37kw

Press Save at 8 bars. 9 bars showing (out 16 ) on MMCS when finished test. 7.4L/100k Petrol motor stopped a couple of times. B5 37kw

Press Save at 7 bars. 8 bars showing (out 16 ) on MMCS when finished test. 7.4L/100k Petrol motor stopped a couple of times. B5 37kw

Press Save at 6 bars. 7 bars showing (out 16 ) on MMCS when finished test. 7.4L/100k Petrol motor stopped a couple of times. B5 37kw

Press Save at 4 bars. 5 bars showing (out 16 ) on MMCS when finished test. 7.2L/100k Petrol motor stopped like a proper hybrid. B5 37kw

At 1 bars (normal mode). 1 bars showing (out 16 ) on MMCS when finished test. 7.2L/100k Petrol motor stopped like a proper hybrid. B5 37kw

Note No AC or heater on.

Note The B5 amounts are Regen that I could get at the end of the runs with the paddles set to B5 when turning around.

Note Where I said the petrol motor never stopped it only stopped at each end of the run where I turned around.

Note Where the Petrol motor stopped I read it at the same point of the hybrid cycle.

Note I could not do this test more scientifically without putting it on a dyno.

Note I have just lost 6 hrs out of my life.

Note There are no more Notes. :lol:

Regards Trex.

 

[Trex]

I just need to look at graphing those results now.

I hope everyone can understand what I wrote.

Ask questions if you do not.

Regards Trex.

 

[Titan]

So, you save the most, but at best just over half a litre per 100k, by running in Save mode when the battery is less than half full. Interesting. Not much in it.

 

[Titan]

7.8 l/100k - > 36.25 mpg
7.4 l/100k - > 38.17 mpg
7.2l/100k - > 39.23 mpg

 

[Trex]

So, you save the most, but at best just over half a litre per 100k, by running in Save mode when the battery is less than half full. Interesting. Not much in it.

Yes. It will depend on the individual whether it is worth it. But over the lifetime of ownership it may add up to a fair amount.

Regards Trex.

 

[Trex]

7.8 l/100k - > 36.25 mpg
7.4 l/100k - > 38.17 mpg
7.2l/100k - > 39.23 mpg

Thanks for converting Titan. I sometimes forget. Sorry about that.

Regards Trex

 

[Titan]

So, you save the most, but at best just over half a litre per 100k, by running in Save mode when the battery is less than half full. Interesting. Not much in it.

Yes. It will depend on the individual whether it is worth. But over the lifetime of ownership it may add up to a fair amount.

Regards Trex.

Possibly but for drive "comfort" I'd rather have charge in my battery. I find the engine racing when under load in Save and low battery too off putting.

I've been running a few unscientific tests of my own, on a 150 mile trip I undertake fairly regularly, and at present running Charge as soon as able to engage parallel mode is most efficient. I've just installed Torque Pro to try and make it a slightly more quantifiable test. Just need to find the post about the pids to use.

 

[Trex]

So, you save the most, but at best just over half a litre per 100k, by running in Save mode when the battery is less than half full. Interesting. Not much in it.

Yes. It will depend on the individual whether it is worth. But over the lifetime of ownership it may add up to a fair amount.

Regards Trex.

Possibly but for drive "comfort" I'd rather have charge in my battery. I find the engine racing when under load in Save and low battery too off putting.

I've been running a few unscientific tests of my own, on a 150 mile trip I undertake fairly regularly, and at present running Charge as soon as able to engage parallel mode is most efficient. I've just installed Torque Pro to try and make it a slightly more quantifiable test. Just need to find the post about the pids to use.

Yes but for people that do not want too much hassle when driving the Phev they could just take their Drive battery straight down to 1/4 SOC and still have a bit of charge left in the battery and it would be still very efficient. But it might be more than 1/4 SOC I should have done more tests. :lol:

Regards Trex.

 

[greendwarf]

Just to throw a small spanner into the works :lol:

If I understand this correctly - you spent some 4 hours at around 100kph on repeat runs and used about 30 litres of petrol. So presumably some (perhaps small) part of the improvement in consumption will have been due to the gradual decrease in weight :?:

Putting this aside, I assume this shows that it is the engine management software that is designed to run the engine at a higher power output (and more efficiently) at lower battery levels - possibly to try to recover battery faster - irrespective of having set Save, rather than something inherent in the physics of hybrid EV technology. If so this is presumably a mistake by Mitsu which can be corrected to improve overall consumption. :mrgreen:

 

[Trex]

Just to throw a small spanner into the works :lol:

If I understand this correctly - you spent some 4 hours at around 100kph on repeat runs and used about 30 litres of petrol. So presumably some (perhaps small) part of the improvement in consumption will have been due to the gradual decrease in weight :?:

Putting this aside, I assume this shows that it is the engine management software that is designed to run the engine at a higher power output (and more efficiently) at lower battery levels - possibly to try to recover battery faster - irrespective of having set Save, rather than something inherent in the physics of hybrid EV technology. If so this is presumably a mistake by Mitsu which can be corrected to improve overall consumption. :mrgreen:

Actually I put $30 of fuel in the Phev about 1/2 way through the tests and rerun the previous test I just did. It made no difference in my result.

See I tried to be as scientific as possible.

That why it took so long.

I even did one run with the AC on because it is bloody hot here but it DID make a difference so I had to rerun that test.

The things I do. :lol:

As for the rest of your post I think I should stay out of that. :lol:

Regards Trex.

 

[slowrunner]

Hi, newbie - lurking 'till now as I don't yet actually possess a PHEV (fingers crossed for the end of the month), but I'm really keen to be able to get the very best out of it.

Can I check I understand the data ?

Did you start each run with a full charge and hit SAVE at later and later points or start each run when you hit SAVE ?

I'm guessing the latter or else each run has a different amount of 'help' from the battery.

 

[gwatpe]

I've just installed Torque Pro to try and make it a slightly more quantifiable test. Just need to find the post about the pids to use.

I have used the PID's

instant consumption
speed
trip average consumption
engine LOAD
trip average speed
engine RPM

added to the logging PID's section in Torque, in this order.

I use a WiFi adapter and log data at 2 second intervals.

The files are .csv, but I open them in Excel and resave them with a different name as .csv. Files are changed with addition of linefeeds with carriage returns.

I have written an application for windows PC that can rapidly graph the data and allow careful examination of the data and calculates the fuel consumption, distance traveled, average speed and average petrol economy for the selected data. The graphs I posted on http://www.myoutlanderphev.com/forum/viewtopic.php?f=10&t=1936 were prepared with this app. This saves the tedium associated with graphing with Excel.

I cannot attach to a gmail email, as it is an .exe file, even when .zipped. I have analyzed other PHEV owners data who are not on the forum.

I won't be offended if you have another graph program preference.

I have not commented on comparison mileage data presented here as other factors are in play, as my PHEV was loaded and ambient temp was over 30C. I did not record exactly the same behavior of fuel consumption vs %SOC as presented here..

I found that in a test with ICE turning ON and OFF that the mark space ratio affects the calculations and it will not be known how good the data is without careful analysis. There will always be a time to get single point data, but following up with logging will give more insight as to what is going on.

Still good to have more ways we can work out how the PHEV works. I am trying to use normal driving rather than special trips to gather data, as not often we have opportunity to have an effective test track.

 

[greendwarf]

Just to throw a small spanner into the works :lol:

If I understand this correctly - you spent some 4 hours at around 100kph on repeat runs and used about 30 litres of petrol. So presumably some (perhaps small) part of the improvement in consumption will have been due to the gradual decrease in weight :?:

Putting this aside, I assume this shows that it is the engine management software that is designed to run the engine at a higher power output (and more efficiently) at lower battery levels - possibly to try to recover battery faster - irrespective of having set Save, rather than something inherent in the physics of hybrid EV technology. If so this is presumably a mistake by Mitsu which can be corrected to improve overall consumption. :mrgreen:

Actually I put $30 of fuel in the Phev about 1/2 way through the tests and rerun the previous test I just did. It made no difference in my result.

As for the rest of your post I think I should stay out of that. :lol:

Regards Trex.

Actually I've thought about this again and now conclude there is good reason the software works this way because we know that the batteries can accept charging faster at lower SoC thus putting greater load on the ICE and so greater efficiency & consumption. So it IS the EV physics (of the batteries) that are dictating the programming If so, then this should apply to either the mini-charge cycles under Save or Charge itself, i.e. the car will always run the ICE more economically when the SoC is lower.

 

[anko]

Actually I've thought about this again and now conclude there is good reason the software works this way because we know that the batteries can accept charging faster at lower SoC thus putting greater load on the ICE and so greater efficiency & consumption. So it IS the EV physics (of the batteries) that are dictating the programming If so, then this should apply to either the mini-charge cycles under Save or Charge itself, i.e. the car will always run the ICE more economically when the SoC is lower.

Thank you, greendwarf! I feel so much less lonely now

 

[anko]

So, you save the most, but at best just over half a litre per 100k, by running in Save mode when the battery is less than half full. Interesting. Not much in it.

Close to ten percent. How so not much in it?

 

[anko]

Possibly but for drive "comfort" I'd rather have charge in my battery. I find the engine racing when under load in Save and low battery too off putting.

Yesterday, I posted this picture:

It shows my car accelerating while towing a caravan. It does so with the ICE running at 2.484RPM (at 91 km/h, so totally what you would expect in parallel mode) and the battery adding more than 60 kW to the ICE power. Even though SOC is as low as 23.5 (!) %. I still wonder what one must do to a PHEV and for how long in order to get it revving as a result of low SOC.

I've been running a few unscientific tests of my own, on a 150 mile trip I undertake fairly regularly, and at present running Charge as soon as able to engage parallel mode is most efficient. I've just installed Torque Pro to try and make it a slightly more quantifiable test. Just need to find the post about the pids to use.

I am curious to what you will find, as your current findings go against what many others seem to experience and also against logic. Please do NOT look at instantaneous fuel consumption by itself as this indeed will be lowest with a full battery. But it is the average consumption that counts, and I expect this will be lower when %SOC decreases and %EV increases.

 

[Titan]

So, you save the most, but at best just over half a litre per 100k, by running in Save mode when the battery is less than half full. Interesting. Not much in it.

Close to ten percent. How so not much in it?

Nearer 7% but either way, half a litre over 100km equates to over 560 miles per gallon, so in the grand scheme of things, well for me anyway, hair splitting.

 

[anko]

Nearer 7%

Now who is hair splitting? :mrgreen: But isn't hair splitting what a Technical Discussions section is about?

 

[Titan]

Nearer 7%

Now who is hair splitting? :mrgreen: But isn't hair splitting what a Technical Discussions section is about?

:mrgreen:

To be honest, I'm still not convinced which method is best for best mpg (and nobody say "pure ev" please ) Now I've got torque pro I'm hoping to get a better feel for it, because reading all these different reports is doing my head in :roll:

 

[Trex]

Hi, newbie - lurking 'till now as I don't yet actually possess a PHEV (fingers crossed for the end of the month), but I'm really keen to be able to get the very best out of it.

Can I check I understand the data ?

Did you start each run with a full charge and hit SAVE at later and later points or start each run when you hit SAVE ?

I'm guessing the latter or else each run has a different amount of 'help' from the battery.

Hi slowrunner,

First run full charge and press save. Get out on test section and get up to speed and press reset on Phev's fuel computer. Do test in both directions fully then take measurements.

Press Save button again to turn it off and reduce drive battery charge on the freeway down to next test point. Reduces very quickly at highway speeds.

Press Save button again to turn back on and press reset on fuel computer etc, etc.

I hope that explains it.

Regards Trex.