Fuel economy and how to save fuel. What can we agree on.?

[Trex]

Hi Claymore,

I find a good Scotch Whiskey helps my headaches when I do not understand things which can be fairly often in my life.

Just keep asking questions if you do not understand. I do.

Regards Trex.

 

[Trex]

Well as a non-techy, non-engineer, non-mechanical type, just a regular everyday driver, can I offer my tuppence-worth!

Have had the PHEV since 8 September and until last week and about 840miles in had not used any petrol, then had a couple of shortish fast road journey and on each one using the save button, but then noticed all this chatter here and elsewhere about buttons/modes and fuel economy. So, yesterday I decided to try my own little experiment. As you can imagine, 6 weeks, 840 miles and all EV, this is by far the 'normal' set up for us and as we both work from home, commuting is never an issue and the car always gets the chance to get/remain topped up, but yesterday I went from Edinburgh to Elgin, round trip of 380 miles. So, outward trip first 5 miles on EV and then hit save with 19 miles range and did 60 miles on motorway, 95 miles on the A9, 30 miles on B-roads and 10 miles on A96; got to Elgin with EV range of 22miles, average mpg 34.8. Did a bit of EV driving around town and then headed home and did not touch any buttons at all this time. Took same route home and when I got onto the motorway (M90) after 120 miles driving, hit the charge button getting to the outskirts of Edinburgh with an EV range of 12 miles, which was enough to get to my son's to drop him off and then home, pulling into the drive with EV range of 1 and average mpg of 37.6!

Did I save fuel or money?? Don't really know, but when I used to do this exact same return journey in my previous 9+ year old SAAB estate it would be about 100 litres of petrol overall; tank was 60 litre capacity and it was just over a tank and a half. This time it took just over a tank, but the capacity is 40 litres, so I would say 50/55 litres! Now while a diesel vehicle would obviously give me masses more mpg, I do this 3-4 times a year, so it suits me!

Hi lg1726,

You certainly can offer your tuppence-worth. Now that is a saying I had not heard for years here in Australia (we converted from pounds, shillings and pence in 1966)

I am glad to read that that you pressed the charge button. Some people around here seem to be scared of it. :lol:

If you go to the same destination regularly you should be able to try the different modes and test out what works best for you.

Regards Trex.

 

[anko]

With high SOC: https://www.dropbox.com/s/fadf2k3yy9e20lh/TC 2015-10-26 16-40-49-857 (high SOC).xlsx?dl=0
With low SOC: https://www.dropbox.com/s/mvolefzhcggng5m/TC 2015-10-26 17-18-53-437 (low SOC).xlsx?dl=0

On the second tab of each file, you find a graph with various params:

- speed
- load
- RPM
- C-Power (combined power of both motors, + means propelling, - means breaking)
- B-Power (battery power (+ means charging, - means discharging)

You can see, at high SOC, battery recharge is pretty much stable at approx 3.6 kW and engine load varies to match driving conditions.
With low SOC, battery recharge is higher in average an way higher during peaks (even when you ignore the peaks that take place during regen) and fluctuates to match driving conditions, where load is much more stable.

 

[Trex]

With high SOC: https://www.dropbox.com/s/fadf2k3yy9e20lh/TC 2015-10-26 16-40-49-857 (high SOC).xlsx?dl=0
With low SOC: https://www.dropbox.com/s/mvolefzhcggng5m/TC 2015-10-26 17-18-53-437 (low SOC).xlsx?dl=0

On the second tab of each file, you find a graph with various params:

- speed
- load
- RPM
- C-Power (combined power of both motors, + means propelling, - means breaking)
- B-Power (battery power (+ means charging, - means discharging)

You can see, at high SOC, battery recharge is pretty much stable at approx 3.6 kW and engine load varies to match driving conditions.
With low SOC, battery recharge is higher in average an way higher during peaks (even when you ignore the peaks that take place during regen) and fluctuates to match driving conditions, where load is much more stable.

Hi anko,

Thanks for sharing. Amazing.

I have to go now but will try to have a good look at it later.

Again thanks.

Regards Trex.

 

[gwatpe]

I have so far only managed to record some speed and petrol consumption data, with basic Torque PRO.

The way the PHEV works is starting to be more clear. Need a better test track now.

Here are pics of some data plotted from today.

vertical lines are approx 5 minutes apart.

First is drive section to city outskirts.

Battery was down a few bars from full at the start.

In the centre of the graph, battery was drawn down in NORMAL mode, to half full to allow for heavy REGEN down a steep hill.

Next pic for return journey. Battery was indicated at half full and in SAVE mode. Was about 35 minutes of driving. Averaged out at 6.1L/100km and 46%EV by the PHEV computer. had to climb some big hills and come back down again.

The petrol consumption is continually adjusted between an upper and lower bound. I am yet to record any constant type data. Will see how I go tomorrow on a trip with less hills and hopefully less traffic.

Will be making a new app to view my particular data logs in a rapid way, with a normalized scaling, to make it easier to compare data. Unfortunately don't have the same mods as "anko" so no EV specific PID's yet. Would be good to have a PID that output the economy that the PHEV was displaying on the dash, so it could be recorded and compared.

Once you can see how the PHEV is continually making adjustments to the ICE operation you will come to a conclusion of just how difficult it is going to be to work a strategy into a typical drive that results with consistent economy improvement. The general driving points Trex has suggested will help, but many drivers will be fighting with the PHEV computer when trying to push buttons in the hope of some measurable economy improvement. Many forum readers are finding difficulty reproducing economy from drive to drive with majority of ICE operation. The lack of factory supplied instrumentation is an indicator that MMC had difficulty getting reproducible driving styles. The lap times instrumentation has been omitted from the released version as an example. This is detailed in the manual and would be invaluable as a tool to help drivers learn to improve driving economy.

I have no simple strategy that works with day to day car loading as well as traffic, terrain and weather changes.

 

[Claymore]

Hi Claymore,

I find a good Scotch Whiskey helps my headaches when I do not understand things which can be fairly often in my life.

Just keep asking questions if you do not understand. I do.

Regards Trex.

Trex, I've just caught up with the latest series of posts here and my head is fit to burst!

One minor technical issue I feel qualified to comment on however is that Scotch is 'whisky' rather than 'whiskey' and whilst I enjoy both, tonight's consumption of the former has not helped my appreciation of the current flood of analytical info.

JimB

 

[Trex]

Hi Claymore,

I find a good Scotch Whiskey helps my headaches when I do not understand things which can be fairly often in my life.

Just keep asking questions if you do not understand. I do.

Regards Trex.

Trex, I've just caught up with the latest series of posts here and my head is fit to burst!

One minor technical issue I feel qualified to comment on however is that Scotch is 'whisky' rather than 'whiskey' and whilst I enjoy both, tonight's consumption of the former has not helped my appreciation of the current flood of analytical info.

JimB

:lol:" 'whisky' rather than 'whiskey' ". Here we just call it "Scotch" so it is not a word I use regularly. We often spell it whiskey in Australia which I now know is more a Irish, American type of spelling.

"tonight's consumption of the former....". You may just need 1 more "Scotch".

Or ask more questions.

Regards Trex.

 

[Trex]

The general driving points Trex has suggested will help, but many drivers will be fighting with the PHEV computer when trying to push buttons in the hope of some measurable economy improvement. Many forum readers are finding difficulty reproducing economy from drive to drive with majority of ICE operation. The lack of factory supplied instrumentation is an indicator that MMC had difficulty getting reproducible driving styles. The lap times instrumentation has been omitted from the released version as an example. This is detailed in the manual and would be invaluable as a tool to help drivers learn to improve driving economy.

I have no simple strategy that works with day to day car loading as well as traffic, terrain and weather changes.

Thanks for the graphs gwatpe.

After owning hybrids for a while now I still love the way that petrol motor shuts down and uses no fuel when travelling at speed.

I wish my father was alive to see these graphs of that happening (died just before I got my first hybrid). He would have loved the technology.

"The general driving points Trex has suggested":

I would like to think of them as our (forum members) suggestions and if they are something we agree on can be used for future reference and added too as necessary.

"Many forum readers are finding difficulty reproducing economy from drive to drive with majority of ICE operation.":

I find that if I am travelling to the same distant destination and just by using the phev's own fuel computer and by testing different modes I can get a reproducible results that shows the advantages of different modes.

But the major point here is "same distant destination" where you can compare the results and that may not work for everyone but does for me. And yes some results need to be "thrown out" if major differing conditions cause a problem with the data and that data needs to be validated more than once.

When I wrote that it sounds harder than it actually is to do. :lol:

Regards Trex.

 

[Trex]

You can see, at high SOC, battery recharge is pretty much stable at approx 3.6 kW and engine load varies to match driving conditions.
With low SOC, battery recharge is higher in average an way higher during peaks (even when you ignore the peaks that take place during regen) and fluctuates to match driving conditions, where load is much more stable.

Yes you can certainly see what you are saying in this data.

So I was getting confused thinking this was the charge rate for charge mode ie when you said "18kw" I am thinking "wow this would charge the battery a lot quicker than I see on my Phev". Like roughly 15min for 1/2 a charge not counting losses.

I cannot wait to see some charge mode graphs which is what I use (charge mode regularly).

All in all very interesting.

Regards Trex.

 

[jthspace]

Well, to add my two-penneth worth, highly non-technical, but "wot I has done" since I got the car earlier in the month. I have used Fuelly to record the information, but only two "fill-ups" and I ignored the quarter tank that was in it when I got the car.

My type of driving so far : 80% highway / fast road / 20% local

Local driving (for example Home to Cambridge and return - 20 miles round trip) - 100% EV

Out of town driving - first long trip - used "save" and "charge" - 100 mile round trip

Out of town driving - next trip - used EV as much as possible, charge, EV at destination. EV on return, charge, EV to home and arrived with 10%. Fast trip up to 85 mph / 135 kph on the motorway.

Out of town driving today (new style after reading posts on here) - used EV until 2 bars were showing, hit charge and recharged up to 60%, used EV until back to 2 bars, hit charge, used EV so as to arrive home with three bars. 90 miles approx. Motorway both ways, 5 miles non motorway. Speed was generally "fast" as above where possible (over 50% of the journey).

I am not, at this stage, looking to drive "economiclly" but to "drive from a to b" but I will when the fun of driving this car has worn off (a bit).

Average fuel usage on the one full tank is currently 42mpg (6.7 litres per 100 kms) - which is better than my Nissan Juke 1600cc CVT ever managed - and which I am pretty happy with and ignoring what the few electricity recharges have cost me.

Sorry, no graphs . . . . .

Jeff

 

[Trex]

Well, to add my two-penneth worth, highly non-technical, but "wot I has done" since I got the car earlier in the month. I have used Fuelly to record the information, but only two "fill-ups" and I ignored the quarter tank that was in it when I got the car.

My type of driving so far : 80% highway / fast road / 20% local

Local driving (for example Home to Cambridge and return - 20 miles round trip) - 100% EV

Out of town driving - first long trip - used "save" and "charge" - 100 mile round trip

Out of town driving - next trip - used EV as much as possible, charge, EV at destination. EV on return, charge, EV to home and arrived with 10%. Fast trip up to 85 mph / 135 kph on the motorway.

Out of town driving today (new style after reading posts on here) - used EV until 2 bars were showing, hit charge and recharged up to 60%, used EV until back to 2 bars, hit charge, used EV so as to arrive home with three bars. 90 miles approx. Motorway both ways, 5 miles non motorway. Speed was generally "fast" as above where possible (over 50% of the journey).

I am not, at this stage, looking to drive "economiclly" but to "drive from a to b" but I will when the fun of driving this car has worn off (a bit).

Average fuel usage on the one full tank is currently 42mpg (6.7 litres per 100 kms) - which is better than my Nissan Juke 1600cc CVT ever managed - and which I am pretty happy with and ignoring what the few electricity recharges have cost me.

Sorry, no graphs . . . . .

Jeff

Hi Jeff,

I agree, just enjoy the Phev for a while and experiment when you are ready (which you already seem to be doing).

Just looked up the Nissan Juke 1600cc CVT fuel economy and I think it shows 10L/100k on highway. So you would be very happy if I have that right.

I remember when 30mpg (we used mpg for comparisons long after we converted to metric here in Australia) in a smaller saloon type car was considered exceptional and it does not seem that long ago.

It seems quite a few forum members are getting around the 40mpg mark not counting the grid charge. In a 4wd with a petrol motor. It still amazes me.

Hybrid technology is still making me "child like" in fascination.

Regards Trex.

 

[jthspace]

Yep, why the hell we are not building these in big numbers amazes me - we have one of the most successful car building industries in the World here in the UK (OK, not much owned by us anymore) - with Nissan exporting cars built here all over the World and even back to Japan. We (I mean the Government) should be funding development and demanding that X% of cars are Hybrid by 2020.

Look at the mess VW (and probably others) are in with diesel fudging tests (and now petrol engines as well, apparently). We have horrendous pollution figures in the UK (which are being selectively ignored), most major cities are over Euro limits, making Hybrid the natural short-term fix for the time being.

OK off my hobby-horse now . . . .

 

[jthspace]

Just looked up the Nissan Juke 1600cc CVT fuel economy and I think it shows 10L/100k on highway. So you would be very happy if I have that right.

That's the "public" figure - in practice I actually got something slightly better, surprisingly.

Mind you, I am looking forward to 140 mpg (2L/100km) that Mitsubishi advertise. :lol:

 

[Neverfuel]

You can do it - but you won't be venturing far from a socket for your charger for a month or two

 

[jthspace]

You can do it - but you won't be venturing far from a socket for your charger for a month or two

Extension lead . . . .

 

[Vince31]

So here is a controversial way of improving economy and MPG:

On a motorway drive close and stay behind a large box van/lorry which typically stay at 60MPH and benefit from the huge drafting effect. With Adaptive Cruise Control to maintain a minimum safe distance this should now be feasible and much safer than before (without Adaptive Cruise). What do you think?

 

[maby]

So here is a controversial way of improving economy and MPG:

On a motorway drive close and stay behind a large box van/lorry which typically stay at 60MPH and benefit from the huge drafting effect. With Adaptive Cruise Control to maintain a minimum safe distance this should now be feasible and much safer than before (without Adaptive Cruise). What do you think?

I think that your insurance company would disapprove

 

[anko]

So here is a controversial way of improving economy and MPG:

On a motorway drive close and stay behind a large box van/lorry which typically stay at 60MPH and benefit from the huge drafting effect. With Adaptive Cruise Control to maintain a minimum safe distance this should now be feasible and much safer than before (without Adaptive Cruise). What do you think?

The minimal ACC distance is way way to long to benefit from draft. I think.
Could even be counterproductive: air is not lifted over the car, but crashes onto your hood / windshield. But I think even that may not happen at such distance.

 

[Neverfuel]

So here is a controversial way of improving economy and MPG:

On a motorway drive close and stay behind a large box van/lorry which typically stay at 60MPH and benefit from the huge drafting effect. With Adaptive Cruise Control to maintain a minimum safe distance this should now be feasible and much safer than before (without Adaptive Cruise). What do you think?

I wrote a whole post on why not to do this, but decided to delete it as it sounded too sarcastic.

Needless to say - give it up and stay safe.

 

[jaapv]

I think that it is a good thing you have FCM... A truck has a shorter braking distance than a car - good luck.