Australian ROAD TRIP.

[anko]

I would do it this way:

- First deplete the battery on the first 30 km or so.
- Then reset the trip computer
- Then record %EV over the next 120 km

This is an apples and oranges test.

Today, I will do my little test. Still don't know why it would not be valid ...

 

[anko]

I would do it this way:

- First deplete the battery on the first 30 km or so.
- Then reset the trip computer
- Then record %EV over the next 120 km

Small issue: reseting the trip computer does not reset %EV drive. But ..... with some math we should be able to figure it out.

On the way down there: I did 35 km before the engine started. Obviously, %EV was 100% at that time. Then after another 35 km, the %EV reading had dropped to 70%. So, 30% of 70 km (21 km) was non EV, all in the last 35 km. 21 non EV km during 35 km translates to 14 EV km during 35 km, which is 40 %. Later, after 105 km in total, %EV had dropped to 62%. So, 38% of 105 km (40 km) was non EV, all in the last 70 km. This translates to 30 EV km in the last 70 km, which results in 43% EV.

On the way back, conditions must have been a little bit better, although I did only 31 km before the engine started (heater was on). After 136 km, the %EV was down to 59%. So, 41% of 136 km (56 km) was non EV. 56 non EV km during 105 km translates to 49 EV km during 105 km. This results in 46.6% EV.

This seams like an awful lot. On the other hand, at any time when the engine was running, fuel consumption was 10.8 l / 100 km (only sometimes 10.7).
Now, on the trip down there, the average fuel consumption, after being reset when the engine first engaged, was 7.1 l /100 km. In order for the fuel consumption to average out at 7.1 would mean the engine had to be running about 65% of the time, resulting in 35% EV drive. Not quite 40 or 42 but still way higher than 15%.
On the return trip, the overall consumption, without a reset, was 5.2 l/100 km. Measured over 136 km this means 7.1 liters. So I have used 7.1 liters of fuel during 105 km, resulting in 6.7 l / 100 km, measured from when the battery was depleted. In order for the fuel consumption to average out at 6.7 would mean the engine was running 62% of the time, resulting in 38% EV drive.

I wouldn't want to bet that I had actually achieved 40% or even 35% of EV driving, but 15% seems rather low to me. Anything wrong with my reasoning?

Two other things I noticed today:
- EV driving does not stop at 126 real km/h (as I thought before), but at exactly 120 km/h (this is 126 km/h on the dash).
- When driving faster than 120 km/h, the engine is running all the time but still SOC does it's normal cycle. Where at 100 km/h the engine load alternates between 75% (parallel hybrid mode) and 0% (EV mode), at 122 km/h it alternates between 75% and approx. 55%. Possible explanation: E-power is used to eliminate electromagnetic drag in both E-motors and the generator. This power is, although not shown on the energy flow diagram, taken from the battery. At these times, the engine needs to run at approx. 55% load to propel the car. When SOC drops below the known threshold, the engine starts to work a bit harder in order to enhance SOC again. And so on.

 

[gwatpe]

My results were from my Road trip, as I had already said. The car was fully loaded, and not just empty with a driver.

The results that "anko" has shared are with a PHEV operating with essentially an empty battery. For a regular, well known drive, an empty battery may be OK. The EV balance does seem higher when the battery is empty. How much easier would it be if we had decent numerical data from our cars for comparisons.

I won't be able to provide any useful comparisons because my driving needs require a significant amount of reserve battery for a longer drive due to low speed city needs as well as steep hills. Unfortunately, even if there is a minor economy benefit of driving with an empty battery, I cannot make much use of it. Other drivers with similar typical drives to "anko" may benefit from operation of the PHEV with the battery depleted in the first instance.

I can still have local EV driving, at close to 100%EV.

 

[anko]

My results were from my Road trip, as I had already said. The car was fully loaded, and not just empty with a driver.

Hmmm, earlier you wrote:

There is still about 15%EV driving, with ICE operation cycling that still occurs at 100kph.

Must have misunderstood
Whether or not my car was loaded would have a very, very minor effect on my test. If any. And apart from that, I brought my wife :lol: .
Towing a trailer, now that would have made an impact :mrgreen:

 

[maby]

My results were from my Road trip, as I had already said. The car was fully loaded, and not just empty with a driver.

The results that "anko" has shared are with a PHEV operating with essentially an empty battery. For a regular, well known drive, an empty battery may be OK. The EV balance does seem higher when the battery is empty. How much easier would it be if we had decent numerical data from our cars for comparisons.

I won't be able to provide any useful comparisons because my driving needs require a significant amount of reserve battery for a longer drive due to low speed city needs as well as steep hills. Unfortunately, even if there is a minor economy benefit of driving with an empty battery, I cannot make much use of it. Other drivers with similar typical drives to "anko" may benefit from operation of the PHEV with the battery depleted in the first instance.

I can still have local EV driving, at close to 100%EV.

These figures are extremely dependent on both driving style and conditions. With a fully charged battery driving around town, I generally don't get much better than 90% EV - you really do need a pretty gentle right foot to avoid the engine starting on acceleration from a standing start or overtaking. Cruising on a relatively straight , flat road in light traffic at 30mph is very different.

 

[Grigou]

I wouldn't want to bet that I had actually achieved 40% or even 35% of EV driving, but 15% seems rather low to me. Anything wrong with my reasoning?

No

I said I think that % EV @ 100 km/h is much more than 15 %, too ...

Thank you for the measurements, that confirms my (very) rough estimate made on motorway at 120 km/h in Save mode (which gives an alternance of parallel and EV mode of course).

I just looked at the approx. time of parallel mode vs EV mode for every alternance during about 15'-20' and I remember that it was obviously more than 15 % EV, even at 120 km/h (125 on dashboard)