Fuel economy. I now think my Phev is a lemon.

[Trex]

On Polish motorways the speed limit is 140 km/h.
With empty battery I can hardly get below 10 l/100km at this speed.
By strong wind I burned recently 10.5 l/100km.

Nevertheless, my overall average over the 24.000 km since new stays by 5.8l/100km.

I wouldn't call it "lemon" for a 2t, AWD SUV.

Thanks for that reading at 140kph PolishPilot,

Cannot do 140kph around here (110kph max ) so cannot compare but the figure sounds very believable.

I was being sarcastic or joking when I said lemon actually. It is just some of the figures thrown around here on the forum has me wondering "what the hell" or "Does that include grid charge"?

Did I read somewhere here on the forum that you fly planes (and with your avatar). Can I ask what type?

Regards Trex.

 

[Trex]

With empty battery I can hardly get below 10 l/100km at this speed.

At 140 km/h, I would think SOC wouldn't really matter? Come to think of it, at any speed it shouldn't matter.


Unless you keep it above 50% or even higher. Then I would expect MPG to worsen.

I think he is telling me that no grid charge is include in his measurement.

If the SOC had been reduced over the length of the measurement and that SOC came from the grid then we have a grid charge biased measurement which I for one would like to know when I compare.

 

[Trex]

Anko has long argued that this will be less efficient than letting the battery run down early since the car is less able to dump excess power into a full battery. His belief, which makes theoretical sense, is that if the battery is allowed to run flat, then the car will go into a cycle of running in parallel hybrid for a few miles during which time it will also build up some charge in the battery and it will then switch to EV mode to use up that charge. This should allow the engine to run at its most efficient point and produce a better overall fuel consumption. Trouble is that, while it sounds OK in theory, nobody has ever tested it as far as we could tell. Following discussion with anko, I ran a first test yesterday...

.

anko has mentioned that once or twice :lol: ( anko's 50% rule I call it) but I think he is more going on the fuel flow from OBD2 readings that he has shown and even logged.
see http://www.myoutlanderphev.com/forum/viewtopic.php?f=10&t=1278&start=50 that show a reduction at about 50% SOC.

But if you believe Mitsubishi the Phev will still go into its ev charge ev cycle even at a higher SOC if it can .
see first graph here http://www.myoutlanderphev.com/forum/viewtopic.php?f=10&t=1278

But what I do notice because I charge the phev with the petrol motor quite a lot is the rate of charge slows on my phev noticeable going from 12 to 13 bars and even worse from 13 to 14 bars out of 16 bars (on the MMCS) which stops me driving around with too high a SOC.

But yes taking measurements are the only way to solve these arguments, or we could call them friendly debates.

Ps did your SOC drift when you pressed save? It did on my Phev when I used to do it but from memory we were loaded right up. Or climbing the great dividing range.

 

[anko]

With empty battery I can hardly get below 10 l/100km at this speed.

At 140 km/h, I would think SOC wouldn't really matter? Come to think of it, at any speed it shouldn't matter.


Unless you keep it above 50% or even higher. Then I would expect MPG to worsen.

I think he is telling me that no grid charge is include in his measurement.

If the SOC had been reduced over the length of the measurement and that SOC came from the grid then we have a grid charge biased measurement which I for one would like to know when I compare.

Of course. You are right . But to me this would be so obvious that if somebody mentions the state of charge explicitly I incorrectly assumes he means something more with that.

 

[anko]

But if you believe Mitsubishi the Phev will still go into its ev charge ev cycle even at a higher SOC if it can .
see first graph here http://www.myoutlanderphev.com/forum/viewtopic.php?f=10&t=1278.

I don't think maby or anybody else disputes this (at least at legal speeds). In essence my concernis that the amount of mechanical kWh produced by the engine per liter of fuel is less. So, even if the fuel burn rate burn goes down at higher SOC, the amount of energy produced goes down even faster. So, efficiency deteriorates.

 

[maby]

But if you believe Mitsubishi the Phev will still go into its ev charge ev cycle even at a higher SOC if it can .
see first graph here http://www.myoutlanderphev.com/forum/viewtopic.php?f=10&t=1278.

I don't think maby or anybody else disputes this (at least at legal speeds). In essence my concernis that the amount of mechanical kWh produced by the engine per liter of fuel is less. So, even if the fuel burn rate burn goes down at higher SOC, the amount of energy produced goes down even faster. So, efficiency deteriorates.

And that certainly makes sense - the question is by how much? We are often faced with conflicting pressures in this respect - in my case a journey that starts on the motorway and only the last ten or fifteen miles is at relatively low speeds. It is well documented that EV range drops off rapidly with increasing speed - the primary reason documented for the Save button is to hold back the charge for urban driving. By using up my charge at 60mph, I have probably lost 30% of the range - it would require a significant improvement in fuel consumption at high speed to compensate for that.

 

[Trex]

But if you believe Mitsubishi the Phev will still go into its ev charge ev cycle even at a higher SOC if it can .
see first graph here http://www.myoutlanderphev.com/forum/viewtopic.php?f=10&t=1278.

I don't think maby or anybody else disputes this (at least at legal speeds). In essence my concernis that the amount of mechanical kWh produced by the engine per liter of fuel is less. So, even if the fuel burn rate burn goes down at higher SOC, the amount of energy produced goes down even faster. So, efficiency deteriorates.

Do you mean the electrical kwh produced by the engine through the generator or actual mechanical kw produced.I think you mean the first.

In my opinion the rate of charge slows at the higher SOC (to protect the battery as it should) as seen here,
http://www.myoutlanderphev.com/forum/viewtopic.php?f=10&t=1265&hilit=3.2lts (note the minutes getting longer above 12 up to 14)
which would equal a lower fuel flow rate (generator working less) and because of this you would think it would not be good for the Phev to do its hybrid action of ev, charge, ev etc, and so yes I would also think that efficiency would deteriorate.

But that test was done with the charge button and maby is using the save. Could it be that save does not protect the battery as much and still cycles higher charge rates to do its hybrid thing as his fuel consumption figures seem to infer?

 

[Trex]

And that certainly makes sense - the question is by how much? We are often faced with conflicting pressures in this respect - in my case a journey that starts on the motorway and only the last ten or fifteen miles is at relatively low speeds. It is well documented that EV range drops off rapidly with increasing speed - the primary reason documented for the Save button is to hold back the charge for urban driving. By using up my charge at 60mph, I have probably lost 30% of the range - it would require a significant improvement in fuel consumption at high speed to compensate for that.

I know urban areas (or avoiding series mode) are where I make my biggest fuel savings in my phev from regular trips to the same destination, and recording fuel consumption, using different modes.

 

[anko]

But if you believe Mitsubishi the Phev will still go into its ev charge ev cycle even at a higher SOC if it can .
see first graph here http://www.myoutlanderphev.com/forum/viewtopic.php?f=10&t=1278.

I don't think maby or anybody else disputes this (at least at legal speeds). In essence my concernis that the amount of mechanical kWh produced by the engine per liter of fuel is less. So, even if the fuel burn rate burn goes down at higher SOC, the amount of energy produced goes down even faster. So, efficiency deteriorates.

Do you mean the electrical kwh produced by the engine through the generator or actual mechanical kw produced.I think you mean the first.

I meant the total amount of output in kWh per liter fuel spent. Regardless of it being mechanical (which it initially always is) or electrical.

And that certainly makes sense - the question is by how much? We are often faced with conflicting pressures in this respect - in my case a journey that starts on the motorway and only the last ten or fifteen miles is at relatively low speeds. It is well documented that EV range drops off rapidly with increasing speed - the primary reason documented for the Save button is to hold back the charge for urban driving. By using up my charge at 60mph, I have probably lost 30% of the range - it would require a significant improvement in fuel consumption at high speed to compensate for that.

I know urban areas (or avoiding series mode) are where I make my biggest fuel savings in my phev from regular trips to the same destination, and recording fuel consumption, using different modes.

True. I think it is a great idea to make sure you have SOC available for urban driving. But there is two ways of achieving this:

- save your grid charged power for later, resulting in a relatively high average SOC
- spend your grid charge power directly and rebuild the required SOC only shortly before you need it, resulting in a relatively low average SOC

If you can choose between the two of those (and many of us can), IMHO the second would be best as it allows the engine to run at a higher average rate of efficiency. Of course, EV range (kms or miles per kWh) drops off rapidly with increasing speed. But running Save mode does not stop your car from using electricity at higher speeds at all. In Save mode, (depending on speed and other conditions) up to 40% (?) of the time you are driving in EV mode anyway.

But that test was done with the charge button and maby is using the save. Could it be that save does not protect the battery as much and still cycles higher charge rates to do its hybrid thing ...

I trult don't think so. But with my Torque Pro dashboard I can easily compare battery charge currents between the two. Just waiting for the next opportunity ....

 

[Trex]

But that test was done with the charge button and maby is using the save. Could it be that save does not protect the battery as much and still cycles higher charge rates to do its hybrid thing ...

I trult don't think so. But with my Torque Pro dashboard I can easily compare battery charge currents between the two. Just waiting for the next opportunity ....

Hi anko,

Yes I hoped you would pick up on that. I for one would love to know the results to that question when you have time to do so.

Please post them.

Regards Trex.