[jad03060]

One has to consider how often you're really using 100% of the available power...it just doesn't happen all that much. The ICE is plenty strong enough to move the vehicle smartly without the EV motor assisting. This is more true on the 50e than the 45e, but even with the 45e's smaller output, it doesn't turn into a slug if the battery level is down. And yeah, starting the ICE under high power demand situations feels sort of like a gear shift's typical duration...pretty small and seamless but you can tell if it happens.

[havec]

I’m wondering how good the 50e is at charging the HVB when descending from from a 1000 meter climb. It sure would be nice to recapture as much energy as possible after hauling the 2514 kg vehicle up 1000 meters. (362 kg of it battery weight)
We can do some math based on 1 kWh will lift 966,000 kg 1 meter.
So 1 kWh will lift the 2514 kg 50e 365 meters.
If my math is correct, it should take 2.74 kWh to haul the 50e up 1000 meters Let’s approximately double the power going up to 5 kWh to account for losses due to in the conversion of electric energy to kinetic energy and conversion of kinetic energy to electrical. I would guess that we might capture a little over a kWh going down. Does this sound close to what you 50e and 45e owners are seeing? My 50e just got assigned a VIN so I should know in a couple of months.

[eelnoraa]

Originally Posted by havec

I’m wondering how good the 50e is at charging the HVB when descending from from a 3000 foot climb. It sure would be nice to recapture as much energy as possible after hauling the 2514 kg vehicle up 915 meters. (362 kg of it battery weight)
We can do some math based on 1 kWh will lift 966,000 kg 1 meter.

So 1 kWh will lift the 2514 kg 50e 365 meters.
If my math is correct, it should take 2.5 kWh to haul the 50e up 3000 feet (915 meters). Let’s double the power going up to 5 kWh to account for losses due to in the conversion of electric energy to kinetic energy and conversion of kinetic energy to electrical. I would guess that we might capture a little over a kWh going down. Does this sound close to what you 50e and 45e owners are seeing?

Sorry for being blunt. That highlighted part is way way off. Off by at least factor of 1000. I will share my math when I get to a keyboard

As for regen if 45e descent from a mountain, it depend on how fast you are going. At 75mph down I80 from Tahoe, or down grape vine on I5, you get nothing back. You even need to give energy to maintain the speed. If you are in a traffic jam, doing 10mph, you will get a lot back. The car doesn’t regen at high speed for efficiency optimization

[havec]

Originally Posted by eelnoraa

Sorry for being blunt. That highlighted part is way way off. Off by at least factor of 1000. I will share my math when I get to a keyboard

Thanks for checking the number I pulled off of Google: 1kWh will lift 366 kg 1000 meters.

As for regen if 45e descent from a mountain, it depend on how fast you are going. At 75mph down I80 from Tahoe, or down grape vine on I5, you get nothing back. You even need to give energy to maintain the speed. If you are in a traffic jam, doing 10mph, you will get a lot back. The car doesn’t regen at high speed for efficiency optimization

This is something that is hard to believe because my old Avalon hybrid charged back up to 100% in no time going down.

So zero electric motor braking? How about ICE braking? It must eat up brakes like mad. That’s a lot of weight to control on the downhill. Shame to waste all that potential energy that you paid for hauling that weight up.

[jad03060]

There's a difference between a hybrid and a plug-in hybrid, plus different philosophies across different brands. Then, you'll get different amounts of regeneration on the X5 depending on which mode you're in. In some, it basically just tries to coast with no regeneration unless you're braking. You'd probably get the most regen if in plain hybrid mode going downhill especially if using cruise to where it might even downshift depending on how steep it is to try to maintain your set speed. Depends on the slope and your speed.

[havec]

Originally Posted by havec

I’m wondering how good the 50e is at charging the HVB when descending from from a 1000 meter climb. It sure would be nice to recapture as much energy as possible after hauling the 2514 kg vehicle up 1000 meters. (362 kg of it battery weight)
We can do some math based on 1 kWh will lift 966,000 kg 1 meter.
So 1 kWh will lift the 2514 kg 50e 365 meters.
If my math is correct, it should take 2.74 kWh to haul the 50e up 1000 meters Let’s approximately double the power going up to 5 kWh to account for losses due to in the conversion of electric energy to kinetic energy and conversion of kinetic energy to electrical. I would guess that we might capture a little over a kWh going down. Does this sound close to what you 50e and 45e owners are seeing? My 50e just got assigned a VIN so I should know in a couple of months.

Please don’t bother reading this post because it full of arithmetic errors.
If we can agree that 1 kWh will lift 367,000 kg 1 meter or 367 kg 1000 meter and the 50e weighs 2514 kg, then 2514/367 = 6.85 kWhi is the amount of electrical energy it takes to drive the 50e to the top of a 1000 meter mountain. The potential energy of the 50e is then 6.85 kWh. So going down there is the potential to pick up 6.85 kWh. My question is how much of that potential energy can gained back dropping back down to 0 meters?

[nZtiZia]

the 50e’s 197hp electric motor is capable of producing 145kW. will this help your calculation?

but I would think its power output is rpm-dependent, so it wouldn’t be the descent distance that gives us how much energy is recharged in the HVB, but rather the speed of its descent during that distance. given that, a 1000-meter descent’s energy regeneration will likely vary from person to person, situation to situation...

[havec]

Originally Posted by nZtiZia

the 50e’s 197hp electric motor is capable of producing 145kW. will this help your calculation?

but I would think its power output is rpm-dependent, so it wouldn’t be the descent distance that gives us how much energy is recharged in the HVB, but rather the speed of its descent during that distance. given that, a 1000-meter descent’s energy regeneration will likely vary from person to person, situation to situation...

There are a ton of factors in how much of the potential energy can be recaptured. Road grade and how hard you try to grab some of that 6.85 kWh/1000 meters without pissing off everyone around you. The BMW engineers ran 1000s of simulations on how to maximize the efficiency and make it pleasant to drive. Seems to me you should be able to find some ways to spin that 145 kW generator with 5555 lb of weight under the force of gravity. Might have to dive up Pikes Peak to put it to the real test.

[eelnoraa]

Originally Posted by havec

Please don’t bother reading this post because it full of arithmetic errors.
If we can agree that 1 kWh will lift 367,000 kg 1 meter or 367 kg 1000 meter and the 50e weighs 2514 kg, then 2514/367 = 6.85 kWhi is the amount of electrical energy it takes to drive the 50e to the top of a 1000 meter mountain. The potential energy of the 50e is then 6.85 kWh. So going down there is the potential to pick up 6.85 kWh. My question is how much of that potential energy can gained back dropping back down to 0 meters?

I think this numbers are correct. But do keep in mind, this is based on energy conservation zero parasitic lost, or ideal case scenario. I think this indicate the absolute upper bound for sanity check purpose only.

A more realistic ideal case. 50e will do average of 2mi/kWh flat. Zero potential energy change. Yet burn 6.85kWh in 13.7 miles. So if you descend 3280ft(1000m) in 13.7miles (22km), you will gain zero kWh. This is a 5% grade. This also considering all the PE gets converted into kWh. So real world will be much less than this. Now, grapevine section of I5, average grade is only 6%. If you are flying down grapevine at 75mph, wind drag goes up square of speed, 50e will do less than 2mi/kWh, you will consume kWh doing this.

Originally Posted by havec

This is something that is hard to believe because my old Avalon hybrid charged back up to 100% in no time going down.

So zero electric motor braking? How about ICE braking? It must eat up brakes like mad. That’s a lot of weight to control on the downhill. Shame to waste all that potential energy that you paid for hauling that weight up.

First, Toyota eCVT hybrid/PHEV is a lot more effcient than BMW hybrid. They priority is efficiency, everything else takes a back seat. We know BMW isn't that by design. A SUV as large as Highlander will do 35MPG combine no charging needed. If you don't charge your 50e, treat it like hybrid, you probably get 22mpg combine.

Toyota eCVT hybrid has HVB of 1.2kWh about 100lb. It take no effort to go charge it to 100%. 50e has 20kWh? It will take a lot deliberate effort to charge it to 100%.

Also, I was NOT talking about breaking. I said, if you cruise down grapvine or I80at 75mph, right? If you brake, there is sure regen. I also said, if you going down in traffic jam doing 10mph, you will get a lot of regen, because you are will be constantly braking. Can you get HVB charge from 0 to full in this case, I cannot say. I haven't encounter traffic on that section. However, I can tell you, from Immigrant gap on I-80, stuck in slow traffic, 20-30mph, all the way to Aubrun area, I can get 45e fully charged. another route I can easily get 45e charge from empty to full is coming down from Yosemite on 120.

[Mattl0806]

This is an interesting question - does the 50e battery hold vs the 45e battery control come into play here? I’m assuming not as that would just be so wasteful if the 50e did not regen to max ability bc of it.

In the scenario of coming down the hill in the 50e would it still recapture all of the energy it could despite not being able to set battery hold (missing control) to a higher target figure?

I believe this would just be an opportunity to turn on/off the battery hold button and store the energy permanently in the battery?

[nZtiZia]

Originally Posted by Mattl0806

This is an interesting question - does the 50e battery hold vs the 45e battery control come into play here? I’m assuming not as that would just be so wasteful if the 50e did not regen to max ability bc of it.

In the scenario of coming down the hill in the 50e would it still recapture all of the energy it could despite not being able to set battery hold (missing control) to a higher target figure?

I believe this would just be an opportunity to turn on/off the battery hold button and store the energy permanently in the battery?

some folks have mentioned that’s how they were able to Battery Hold at a higher level than previous

[havec]

An interesting thoughtful discussion here which is much appreciated. How would the 50e do in pure electric mode in slow winding descents. Would the electric motor save the brakes and charge up the battery?

[havec]

“I can easily get 45e charge from empty to full is coming down from Yosemite on 120”.

This is what I really wanted to hear.

[snerkler]

Thanks for all of the replies, however I'm now thinking the X5 50e isn't for me.

I had an extended test drive today and was really disappointed as the lag transitioning from electric to ICE was very noticeable to me on multiple occasions and I must admit I found it frustrating. Also I found the seat a bit uncomfortable, which is really odd as my current F15 X5 seat is one of the most comfortable car seats I've sat in.

Pretty gutted, had my heart set on one.

[eelnoraa]

Originally Posted by Mattl0806

This is an interesting question - does the 50e battery hold vs the 45e battery control come into play here? I’m assuming not as that would just be so wasteful if the 50e did not regen to max ability bc of it.

In the scenario of coming down the hill in the 50e would it still recapture all of the energy it could despite not being able to set battery hold (missing control) to a higher target figure?

I believe this would just be an opportunity to turn on/off the battery hold button and store the energy permanently in the battery?

I don't think it depend on that at all. If you are coming down steep hill slowly, foot half way on brake, regen will be happen regardless of BH. I will still think, the speed of coming down hill play a critical role.

[TurtleBoy]

Originally Posted by snerkler

Thanks for all of the replies, however I'm now thinking the X5 50e isn't for me.

I had an extended test drive today and was really disappointed as the lag transitioning from electric to ICE was very noticeable to me on multiple occasions and I must admit I found it frustrating. Also I found the seat a bit uncomfortable, which is really odd as my current F15 X5 seat is one of the most comfortable car seats I've sat in.

Pretty gutted, had my heart set on one.

What mode were you driving in? Most folks seem to say the transition is seamless or close to it.

[snerkler]

Originally Posted by TurtleBoy

What mode were you driving in? Most folks seem to say the transition is seamless or close to it.

Tried it in all. Obviously in electric only there's no lag, and it's actually nippier than I thought it would be. In "sport" where I believe you force the combustion engine to be on all the time it holds the revs too high and downshifts too much to be an everyday mode (obviously great if you giving it some), however you don't get the lag.

But in hybrid (which I'd assume most folk would use) it's there. Now I guess some people will perceive it more than others, and it will also depend on how you drive, but for me I think living with it day to day would prove annoying. Since having my test drive today I have googled it to see if others experienced the same and it seems that some folk do and some don't, which says to me some are more perceptive/awkward than others, and we all drive differently. I definitely have a heavy right foot

Where I noticed it most is when I wanted to pull out of a t-junction sharply, or pull into a gap on a roundabout (we have LOADS of these in the UK) it was like a very exaggerated turbo lag and then it jolted you when it 'kicked in'.

It's clear to me that it's as the combustion is starting up as I can hear it starting, just like you do when stop/start kicks in on normal combustion engines. In fact now I mention the stop/start it's exactly like that.

Have you ever pulled up to a stop but immediately see a gap in traffic and just as you touch the accelerator the stop/start kicks in and you have to wait momentarily for the engine to restart and you're not sure whether you're going to make it into the gap in traffic due to the delay, it's like that. That's why I always turn stop/start off.

[bono]

I’m a bit surprised by your observations, especially considering our shared experience with diesel engines. The 50e is more flexible in terms of torque compared to the 35d (bi-turbo), and I would expect it to outperform the 30d (single turbo) as well. That said, I won’t argue with your conclusion. However, you must really have a heavy foot if you find the need for an ICE to pull into gaps at roundabouts!

[snerkler]

Originally Posted by bono

I’m a bit surprised by your observations, especially considering our shared experience with diesel engines. The 50e is more flexible in terms of torque compared to the 35d (bi-turbo), and I would expect it to outperform the 30d (single turbo) as well. That said, I won’t argue with your conclusion. However, you must really have a heavy foot if you find the need for an ICE to pull into gaps at roundabouts!

Yeah if I'm going I'm going

I didn't find the 50e was more flexible in torque per se, I just found it downshifted more to accelerate

[Mishoo]

If you have a heavy foot, then the "Sport" mode would've been the best for you. You said it holds the rev too high. Could you have changed to sport at a higher RPM? I'm asking because the point of entry to sport between S1 - S8 would give you a different feel. when I start sport in "S1", it doesn't rev too high.

Anyways, the transition in Hybrid in my 50e is just perfect for me and I don't feel any lag driving in the city with most places about 40-55m/h. My electric mode is not slow in any ways for overtaking and merging as well. At traffic stop and go, I use my electric mode and it jumps ahead of other cars, if I stomp on the pedal.

[snerkler]

Originally Posted by Mishoo

If you have a heavy foot, then the "Sport" mode would've been the best for you. You said it holds the rev too high. Could you have changed to sport at a higher RPM? I'm asking because the point of entry to sport between S1 - S8 would give you a different feel. when I start sport in "S1", it doesn't rev too high.

Anyways, the transition in Hybrid in my 50e is just perfect for me and I don't feel any lag driving in the city with most places about 40-55m/h. My electric mode is not slow in any ways for overtaking and merging as well. At traffic stop and go, I use my electric mode and it jumps ahead of other cars, if I stomp on the pedal.

The transition can indeed be seamless, but there are times for me when it isn’t. The electric motor is indeed nippy, much quicker than I anticipated, however I clearly accelerate hard a lot as I caused the ICE to kick in more than 50% when I set off from a junction, roundabout etc.

In terms of the S1-S8 are you talking gears or are you saying you can ‘fine tune’ the sport mode so S1 is less sporty and doesn’t hold high revs, and S8 is more sporty and holds onto revs?

[jad03060]

Sport mode assumes you want maximum performance, and on most engines, maximum power arrives closer to the upper RPM limits, so yes, it will hold onto the gears to reach those limits. OTOH, maximum efficiency is to get to top gear so the engine can loaf along at lower RPMs. Balancing those two features is an art. If you manually shift, you can control the effects to your liking, but like any manual, if you misjudge things, you often won't achieve the vehicle's maximum capabilities or be as smooth at it. Personally, I prefer smooth versus aggressive acceleration most of the time, especially if I have passengers. In reality, you rarely get where you're going much faster, and certainly tend to use more energy along the way. Once in a while, it can be fun, but in day-to-day operations, I don't find it useful.