[eelnoraa]

I guess I have boring data to share. The trip is from Bay Area (Mountain View area) to Boreal.

First leg, we started after lunch, with full tank and fully charge HVB. I started with sport at home. Reason was to get ICE warmed up enough by the time we got highway. We stopped in Livermore for desert. This leg, the end to end change in elevation is close to zero, but there is hill in between. From the MPG graph, it is should be obvious. Average speed is 55.3MPG, which is very high. The highway cruising part is more like 70-75. MPG is 28.1 as indicated in first picture of car's trip computer. This information is real time. I took this picture at the first highway exit red light. ICE stopped, I switched to EI. As you can also see eDrive mile = 0

2nd picture is from BMW app, this one is only available after I made parked. MPG (ICE + EDrive) is 28.7. The desert place is about ~1.1 miles from highway exit. If I back out 1.1 miles from this reading, I also get 28.06 MPG, which matches the MPG number above.

[eelnoraa]

2nd trip computer capture was at hotel in Grass valley area. Total elevation change from start of the trip to grass valley is about 2400ft. I captured "since charge" the next day before I drove the car. If I use my formula to back out the EDrive miles, I get 27.3MPG for ICE. Total fuel usage is 6.09gallons.

Cross check fuel usage with BMW app, 1.6 + 3.6 + 0.8 = 6 gallons. I would say number is consistent within round off. Total kWh = 0.8 + 3.7 + 1.3 = 5.8kWh => 1.47mile/kWh.

Consider the gain of 2400ft, I would say 27.3MPG isn't bad at all.

[eelnoraa]

Hotel to Ski resort. Here I didn't capture the trip computer, because everyone is existing to hit the slope, including myself. But know the app can be quite accurate for up hill drive, which I will explain later, I think this is a good indicator of of ICE performance. If I use the assumption of 1.47mi/kWh, total Edrive mile is 1.47mile/kWh x 1.5kWh = 2.2 miles. Back 2.2mile off from this, MPG = 18.9

Elevation gain from hotel to ski resort is 4800ft according to google map

[eelnoraa]

It won't be fair if I don't show the reverse trip. We made multiple stops on I-80 until we reach the same exit.

Miles: 12 + 45 on sport mode. = 57 miles
App MPG: 53.6, 53.6. Coincidentally, they are the same.
Fuel: 0.2 + 0.8 gallon = 1 gallon
kWh: 0 + 0.2 = 0.2kWh.

Let's ignore 0.2kWh where as it won't even do one miles. I get 57mpg using mile/gallon. But app says 53.6. Why so much off?? If I divide 57 miles by 53.6MPG, I get 1.06 gallon. So this is the 2nd decimal digit round of error. Because the fuel usage number is so small, 2nd decimal matters. Imagine 0.22 and 0.84 being round off to 0.2 and 0.8.

Probably not much meaning because I lost 4800 feet.

[eelnoraa]

Instead of boring you guys for every stop of the car, here is the last trip computer screen before I have to fill up. I used up all usable HVB and only 28 miles left of gas. Location of fill up is Costco Sunnyvale, so I consider this as a round trip, where all elevation change is cancelled.

Looking at the trip computer, eDrive mile is 31.1 miles. I think this correlate with one full charge pretty well. Using my formula to back out Edrive miles, I get 26.7mpg. And I should be getting 15.17 gallon of fuel. however, ended up pumping in 16.8 gallon. Using (total mile - eDrive)/gallon pump in, I get 24.1mpg. Hmm, I wonder where that 1.63 gallon has gone.

[eelnoraa]

Want to add one observation. The car's trip computer captures a real time mile driven, MPG, ....

However, myBMW doesn't do that. It takes the HVB and gas level at the beginning and at the end of each drive, and use the delta to determine ICE mile, EDrive mile (percentage), MPG, kWh ... At least for downhill, the app will falsely give a higher MPG than actual. As long as end HVB level is higher than begining HVB level, app think eDrive mile is zero.

And I still stand behind my statements for regen being minimal at highway speed in sport mode at least, but I think even on hybrid. And eAssist really doesn't happen much at all even on steep up hill, unless you demand a large acceleration (50%+ throttle input). And the exist of eAssist isn't to improve MPG at all, because under this kind of acceleration demand, MPG is already down the drain. It is there to give you that acceleration at low RPM high gear.

[eluded]

thanks for sharing the data!

[Francolargo]

Originally Posted by eelnoraa

Hmm, I wonder where that 1.63 gallon has gone.

My previous car, a '16 X3 with the 2 liter 4, always gave erroneous mpg data in the trip computer. It was always high by about 5%. I have been hoping that my 50e can be more accurate. On Monday I took an overnight trip of 270 miles and on the way back I kept track of consumption. It included a few errands and my HV battery started with only 6 miles. On the major highway segment I had an average speed of 70.6 mph yielding 28.2 mpg - strong cross winds and ~ 50° F. The summary of trip computer data for the entire return gave a total mpg of 28.4 over 298.3 miles and reported a fuel burn of 10.5 gallons.

OK, I just filled it up from the pump with - oh the pressure! - 10.6 gallons! A tenth of a gallon more than reported by the trip data is a rounding error in this case. I'm not done checking on the accuracy of the car's sensors, but this first try with the 50e is encouraging.

[E91toG05]

I am on a ski trip as well (Lake Placid) with my 45e and it is like it set up for this vehicle. The hotel has a charger (small fee based on amount charged) and the ski resort (Whiteface) has free chargers. So you get yourself up here on gas and then spend the trip on electric, charging while sleeping or skiing. This is where PHEVs shine - road trip on gas and local on electric with zero range anxiety.

[WagonFan]

Originally Posted by eelnoraa

I guess I have boring data to share. The trip is from Bay Area (Mountain View area) to Boreal.

It might be boring, but very solid data.

From your data I read as well that you were not driving heavy footed (aggressive). 70-75 mph for the ICE portion is still low rev.
I as well assume uphill you didn’t do heavy acceleration/braking, but rather consistently followed the flow.

This gave you overall a very respectable result.

Thanks for sharing.

[WagonFan]

Originally Posted by eelnoraa

Looking at the trip computer, eDrive mile is 31.1 miles. I think this correlate with one full charge pretty well. Using my formula to back out Edrive miles, I get 26.7mpg. And I should be getting 15.17 gallon of fuel. however, ended up pumping in 16.8 gallon. Using (total mile - eDrive)/gallon pump in, I get 24.1mpg. Hmm, I wonder where that 1.63 gallon has gone.

You have one unknown here. The fill level. On a 20 gallon tank was it at 18.5 / 19 / 19.5 / 20.
This is a question for the start and for the end.
You easily could be off 1/2 gallon based on the pump, level of car, ambient temperature, temperature of the gasoline itself or other factors.

That’s why I kept track of the actual refill gallons since factory and over time it balances out better than with one trip. And on my 50e I don’t see this big difference between actual and trip computer.

You did it with the 45e, correct?

Next time invite a 50e friend and ask them to go on a trip with you, so that we get a comparison 😉

[Francolargo]

Originally Posted by eelnoraa

And I still stand behind my statements for regen being minimal at highway speed in sport mode at least, but I think even on hybrid. And eAssist really doesn't happen much at all even on steep up hill, unless you demand a large acceleration (50%+ throttle input). And the exist of eAssist isn't to improve MPG at all, because under this kind of acceleration demand, MPG is already down the drain. It is there to give you that acceleration at low RPM high gear.

In the trip I mentioned above, I kept an eye on the electric vs. ICE drive systems while traveling in hybrid eco pro mode with adaptive cruise control. Exactly as OP mentions, it rarely injected electric power. Mostly it seemed to prevent the ICE from needing to significantly increase short-term fuel burn. The two most common situations were a) when a slower driver in front changed lanes allowing acceleration back to the set point, and b) while climbing, road sections that were steeper would draw electric power. The former (a) would dig-in pushing current above that giving 1 mi/kWh and keeping the ICE from downshifting, while the later (b) seemed to stay roughly in the more conservative 5-10 mi/kWh range. I believe it would use more electric power in the hill-climb situation if the HV battery had more charge. My conclusion was that the Hybrid Eco-Pro drive mode is indeed very well designed to minimize petrol burn.

Two other off-topic observations: c) for the first time I used the left shift paddle to downshift in preparation to blow past a wanker, and as soon as I lifted to coast back to cruise set point the transmission shifted back to 8th. Like! And finally, d) I have not been super-impressed with the driver assistance active lane-keeping because I would almost always choose a slightly different line. However, in a gusty crosswind it's really relaxing because the system lag is shorter than my own and I don't have to worry about kissing a semi.

[eelnoraa]

Originally Posted by WagonFan

It might be boring, but very solid data.

From your data I read as well that you were not driving heavy footed (aggressive). 70-75 mph for the ICE portion is still low rev.
I as well assume uphill you didn’t do heavy acceleration/braking, but rather consistently followed the flow.

This gave you overall a very respectable result.

Thanks for sharing.

I just drove the car normally, Not super aggressive but definitely did NOT try to achieve best MPG either. On uphill section, honestly, 45e/B58 is way more than adequate. My pace was faster than most.
X5 is also quite, so I don't even feel I am putting any stress to the car. Then entire section of uphill, I think I see less than total of 2 second of eAssist. How do I know, I have a GoPro mounted on passenger side head rest post. It just captured iDrive screen in lower left. I have energy flow screen on for most of the 4800 climb section. 45 minutes of footage. I fast forward and only find that little eAssist. 19MPG for this section tho.

Originally Posted by WagonFan

You have one unknown here. The fill level. On a 20 gallon tank was it at 18.5 / 19 / 19.5 / 20.
This is a question for the start and for the end.
You easily could be off 1/2 gallon based on the pump, level of car, ambient temperature, temperature of the gasoline itself or other factors.

That’s why I kept track of the actual refill gallons since factory and over time it balances out better than with one trip. And on my 50e I don’t see this big difference between actual and trip computer.

You did it with the 45e, correct?

Next time invite a 50e friend and ask them to go on a trip with you, so that we get a comparison 😉

This is a super good point. Prior to this ski trip, I went to Yosemite in Jan. The fill up on that trip, the pump popped way before the tank was fill, and for some reason I never noticed and thought I got tank filled. Only on the next fill up ( the one before ski trip), I realized trip computer/app (told me I used 8 gallon) and fill up (16 gallon) was way off. Then I realized that pre-matured fill up, I put in 6 gallon only.

Yes, this is 45e. I actually have another family with me in a 23 40i. Very similar drive. I will ask them for their data for 40i vs 45e comparison. I do think I am a smoother driver tho

Originally Posted by Francolargo

In the trip I mentioned above, I kept an eye on the electric vs. ICE drive systems while traveling in hybrid eco pro mode with adaptive cruise control. Exactly as OP mentions, it rarely injected electric power. Mostly it seemed to prevent the ICE from needing to significantly increase short-term fuel burn. The two most common situations were a) when a slower driver in front changed lanes allowing acceleration back to the set point, and b) while climbing, road sections that were steeper would draw electric power. The former (a) would dig-in pushing current above that giving 1 mi/kWh and keeping the ICE from downshifting, while the later (b) seemed to stay roughly in the more conservative 5-10 mi/kWh range. I believe it would use more electric power in the hill-climb situation if the HV battery had more charge. My conclusion was that the Hybrid Eco-Pro drive mode is indeed very well designed to minimize petrol burn.

Two other off-topic observations: c) for the first time I used the left shift paddle to downshift in preparation to blow past a wanker, and as soon as I lifted to coast back to cruise set point the transmission shifted back to 8th. Like! And finally, d) I have not been super-impressed with the driver assistance active lane-keeping because I would almost always choose a slightly different line. However, in a gusty crosswind it's really relaxing because the system lag is shorter than my own and I don't have to worry about kissing a semi.

I mostly agree with (a) and (b), but what does those consumption number mean? I don't think we can see it except in Electric or Electric Individual mode. In any Hybrid, we see MPG. 5-10mi/kWh is super low consumption which both 45e or 50e cannot achieve unless you are on downhill. These car will do 2-3mi/kWh on flat

(c) is not unique to X5 or even BMW. Most if now all BMW auto trans less than say 15 years old do that. My infiniti and Acura SUVs lease before my 45e also do that.

[Francolargo]

Originally Posted by eelnoraa

I mostly agree with (a) and (b), but what does those consumption number mean? I don't think we can see it except in Electric or Electric Individual mode. In any Hybrid, we see MPG.

In hybrid mode in the 50e, you can choose to display the two bar graphs circled by red in the photo. They display in real time - with a small time constant - gasoline consumption (upper bar) and electric usage (lower bar.) The units shown in the photo are displayed when the car is parked, because then they relate to pre-conditioning. These units change when driving to ICE MPG and electric Mi/kWh. So you can track both large and small changes in drive energy both in numerical format (left side) and graphical (bar) format. On electric consumption, the lower the Mi/kWh the more current is going to the electric motor. Small electric assistance to the ICE on a hill might show 5-10 Mi/kWh in the display. While during rapid e-assist acceleration back up to cruise set point the current can increase to under 1.0 Mi/kWh. Make sense now? I personally would prefer to see the actual amperage going into the electric motor, but these units are also informative.

[eluded]

This can be achieved in daily 100% electric driving

Originally Posted by Francolargo

While during rapid e-assist acceleration back up to cruise set point the current can increase to under 1.0 Mi/kWh.

[Francolargo]

Originally Posted by eluded

This can be achieved in daily 100% electric driving

That number is not an average for a whole trip. The point is, this data display lets you monitor moment by moment hybrid energy consumption and even in hybrid eco pro with adaptive cruise control, the car will rapidly accelerate to its set point. Of course that acceleration momentarily pushes the efficiency down, and you can see by how much.