[X5 45e]

Originally Posted by biterror

I think my biggest problem with (how I believe) the estimated range calculation works is that it expects you to recharge one or more times to actually achieve the displayed range. (Ie. keep driving the same you have done in the past.) If it really works this way, it's about as useful as displaying "infinite" as the range and expecting you to refuel when needed.

The display should show how far you can drive _without_ refueling/recharging. That's how it has worked on all my cars before.

I understand that the fuel and electricity consumption varies, and it has to be taken into account - but this is a completely different thing.

Best would be like suggested to show a predictive range on fuel based and the average fuel economy since factory and adapted to the current situation after 10-20 km. This would probably give the best prediction irl driving on fuel only.

The thing that makes it difficult is when suddenly changing driving habits. Because the difference with an PHEV are so significant. Driving electric is 0 L / 100 km on ICE 10 l sporty driving 15 l. With a diesel differences are much smaller between driving styles and won't change the average so fast.

If you always do the same kind of trip the predicted range will be correct.

Maybe do like in the old days. Look at the fuel meter and when it says 1/4 start looking for a gas station.

[aceman]

Originally Posted by biterror

I think my biggest problem with (how I believe) the estimated range calculation works is that it expects you to recharge one or more times to actually achieve the displayed range. (Ie. keep driving the same you have done in the past.) If it really works this way, it's about as useful as displaying "infinite" as the range and expecting you to refuel when needed.

The display should show how far you can drive _without_ refueling/recharging. That's how it has worked on all my cars before.

I understand that the fuel and electricity consumption varies, and it has to be taken into account - but this is a completely different thing.

I totally agree - if they are giving predicted range with the ASSUMPTION that you are going to recharge once, then what's the point? Why don't they give you predicted range with the assumption you are going to refuel as well, or like you say, its no different than saying infinity - that is a big assumption they are making. Its possible your calculation is correct in that they may be thinking this. This would bring my range to about 250 miles on 5/8 of a tank which is still a little overly optimistic but possible IMO. Stupid question, is there anywhere to see the MPG on ICE only?

Aceman

[X5 45e]

Originally Posted by aceman

I totally agree - if they are giving predicted range with the ASSUMPTION that you are going to recharge once, then what's the point? Why don't they give you predicted range with the assumption you are going to refuel as well, or like you say, its no different than saying infinity - that is a big assumption they are making. Its possible your calculation is correct in that they may be thinking this. This would bring my range to about 250 miles on 5/8 of a tank which is still a little overly optimistic but possible IMO. Stupid question, is there anywhere to see the MPG on ICE only?

Aceman

Not directly it will only show average from factory - individual - last fuel - last charge - trip. And that is combined.

When on a road trip and not charging however the "since last fuel" will be the average on fuel only, after the last fuel stop.

The predicted range doesn't make assumptions it just the content of the fuel tank multiplied with the average L/ 100 km from the last xx Km. And because it is a PHEV the average is very variable.

After you did your first fuel only trip you will know how far a full tank will take you and what you can expect. And after driving some time I think the predicted range should be correct anyway. It won't stay on 1000 km for hours when driving on the highway on fuel only.

To summarize: the predictive value is inaccurate to predict your range when driving all electric most of the time and you just left for a long road trip.

[biterror]

Originally Posted by X5 45e

To summarize: the predictive value is inaccurate to predict your range when driving all electric most of the time and you just left for a long road trip.

I still fail to see the value of such a number. The only reason for having such an unrealistic number is to make the car look eco-friendlier than it actually is.

What I really want to know is how far I can drive without refueling/recharging.

Well, I should get my car in the near future, so I can start testing this myself.

[X5 45e]

Originally Posted by biterror

I still fail to see the value of such a number. The only reason for having such an unrealistic number is to make the car look eco-friendlier than it actually is.

What I really want to know is how far I can drive without refueling/recharging.

Well, I should get my car in the near future, so I can start testing this myself.

I don't think there really is a reason. Maybe we shouldn't look for one. 🤓

I don't think it is done intentionally. The problem is that range prediction is done on the same algorithm as in fuel only cars and just added the electric range. The system doesn't know when you leave in the morning that you will take a 1000 km road trip instead of the normal 45 km daily commute you did the last weeks.

Maybe in the future adaptive range prediction will be available based on the destination in navigation. That should give the best prediction if it combines this with your average highway driving style.

[aceman]

I dunno, i still say the formula should be the last 250 miles mpg on ICE only + whatever range you currently have on the battery - that would be fairly accurate. Obviously it can't predict range on any abnormal driving you PLAN on doing (eg all hwy, all city, etc), but at least this method would be relatively accurate for most drivers.

[jad03060]

Originally Posted by aceman

I dunno, i still say the formula should be the last 250 miles mpg on ICE only + whatever range you currently have on the battery - that would be fairly accurate. Obviously it can't predict range on any abnormal driving you PLAN on doing (eg all hwy, all city, etc), but at least this method would be relatively accurate for most drivers.

The prediction becomes more accurate IF you put a destination into the nav system, as then, the vehicle knows your intended route, it knows the speed limits, and the terrain, so can better calculate what kind of energy use is required, and how much regeneration can occur along it. Otherwise, it is using a calculation based on what you've done last. How else could it work?

I'll mention it again...on my ICE, after a long trip, it could easily say after a fillup that I could go over 500-miles. But, after maybe 20-miles of stop and go in the city, it will drop down to maybe 300-miles because it's now assuming you will continue to do stop and go rather than city miles. The car isn't omniscient, you may not agree with its assumptions, but you will learn what they are, and adjust for your expected conditions. That's why there's a fuel gauge and an indication of the battery SOC. Range gets adjusted based on a sliding average of your last x miles. I think the value of x is in the order of 30Km or about 18-miles or so.

On my i3, after going on a different trip, I've been able to drive nearly 14-miles, and the range to empty stayed the same because I was driving in a more economical way. Now, you might say that's peanuts, but that's as much as 1/4 the whole range on that vehicle when it's frigid out. Same company, probably the same programmers, same philosophy, just a bit more involved with a hybrid.

On my X5, up to this point, most of my driving was fairly short trips, but I took a bit longer one, and prior to starting, it said 30-miles of electric range, but I went over 40 on that trip in EV mode because it was low speed, with very few stop signs or lights to require stopping and going...it was mostly just go in the 30-45 mph range.