[Shaw]

Hi Guys,
Regarding the effecient dynamic option on X3: Does it actually revert to electric mode at the stop lights and all that? do you feel any difference? where else do you see that ED being used?
Does it affect the performance?
Does it affect the fuel consumption?
or

[Radioactive]

Here's page 68 of the manual

"Energy recovery
The energy of motion of the vehicle
is converted to electrical energy
while coasting. The vehicle
battery is partially charged and
fuel consumption can be lowered."

It charges the battery. Increase fuel economy. Performance, my guess probably doesn't effect.

[sfax]

You can see in action if you have pro nav (big screen!). The mpg is red and then when you coast it goes to the right and turns blue showing you ED

[sfax]

It looks a bit like this



But you don't get any quantitative feedback on how much fuel you've saved. Benefits are probably wiped out by opening a window

[xDrive35i]

Originally Posted by sfax

It looks a bit like this



But you don't get any quantitative feedback on how much fuel you've saved. Benefits are probably wiped out by opening a window

+1

[Shaw]

Originally Posted by sfax

It looks a bit like this



But you don't get any quantitative feedback on how much fuel you've saved. Benefits are probably wiped out by opening a window

do not see the pic!!!

[bekind]

It works but like others said it is really hard to tell.

Basically it works by disengaging the alternator which under normal use presents some parasitic loss as it is tied to the engines crank via a belt. When you are coasting, the alt disengages and the energy is generated at the wheels.

We are moving towards a world where vehicle accessories will be driven electrically and not mechanically via a direct link to the motor. A few years back all cooling fans were driven off the serpentine belt but now most are moving toward electric fans. Same with the alternator and soon probably even the A/C.

[LEDZEP]

So, BMW has invented and deployed a new technology that can "reduce fuel consumption while coasting"? Well, if they can take credit for that, then I'm going to submit my claim of invention for "reduces coefficient of drag while at rest".

[Bustofa]

Originally Posted by bekind

When you are coasting, the alt disengages and the energy is generated at the wheels.

The alt engages while coasting,surely?

[Lotus7]

Originally Posted by bekind

It works but like others said it is really hard to tell.

Basically it works by disengaging the alternator which under normal use presents some parasitic loss as it is tied to the engines crank via a belt. When you are coasting, the alt disengages and the energy is generated at the wheels.

We are moving towards a world where vehicle accessories will be driven electrically and not mechanically via a direct link to the motor. A few years back all cooling fans were driven off the serpentine belt but now most are moving toward electric fans. Same with the alternator and soon probably even the A/C.

In fact, the alternator is mechanically engaged all the time. It's output is electronically controlled so that once the battery is charged to about 80% of maximum storage, the alternator is electronically switched to a low charge condition during constant speed cruising and then switched to a very high charge condition when the driver releases the throttle and/or brakes the vehicle.

This reduces the engine load during regular driving and recovers energy during braking that would otherwise just add to the brake system heat load.

If the battery drops down to a 50% charge level, the system switches to a constant charge mode like a conventional alternator system. This will typically happen, only if you drive for short distances and start the vehicle a lot without allowing enough driving time to fully recharge the special, deep cycle saturated mat battery.

On the European fuel driving cycle, the BER system results in a 3% fuel efficiency increase. It's a small, but significant advance and does really work.

The downside is that it requires a special high output, modulated alternator, and a larger, more expensive battery, so original cost, and replacement costs are higher in trade for the fuel economy advantage.

[bekind]

Yes, sorry for the typo, I had it backwards. Alternator is engaged when not on the gas pedal.

"With Brake Energy Regeneration, BMW EfficientDynamics points the way to a more energy-efficient future. As soon as you brake or take your foot off the accelerator, the kinetic energy is captured and fed to the battery. This reduces the amount of power the battery takes from the engine and hence lowers fuel consumption. When the driver presses the accelerator, on the other hand, the alternator is decoupled from the drivetrain. With fewer components drawing power from the drivetrain, more of the engine's output can go into accelerating the car."

[Radioactive]

Originally Posted by LEDZEP

So, BMW has invented and deployed a new technology that can "reduce fuel consumption while coasting"? Well, if they can take credit for that, then I'm going to submit my claim of invention for "reduces coefficient of drag while at rest".

LMAO

[CdnE90]

Originally Posted by Lotus7

In fact, the alternator is mechanically engaged all the time. It's output is electronically controlled so that once the battery is charged to about 80% of maximum storage, the alternator is electronically switched to a low charge condition during constant speed cruising and then switched to a very high charge condition when the driver releases the throttle and/or brakes the vehicle.

This reduces the engine load during regular driving and recovers energy during braking that would otherwise just add to the brake system heat load.

If the battery drops down to a 50% charge level, the system switches to a constant charge mode like a conventional alternator system. This will typically happen, only if you drive for short distances and start the vehicle a lot without allowing enough driving time to fully recharge the special, deep cycle saturated mat battery.

On the European fuel driving cycle, the BER system results in a 3% fuel efficiency increase. It's a small, but significant advance and does really work.

The downside is that it requires a special high output, modulated alternator, and a larger, more expensive battery, so original cost, and replacement costs are higher in trade for the fuel economy advantage.

This is one of the most informative posts I've read on this X3 forum.

[Lotus7]

If your X3 has only the standard instrument cluster (without the BER display dial), it's still possible to monitor the operation of the BER system inexpensively by attaching an accessory socket digital voltmeter. In an example of extreme "nerdiness", just to be sure the BER on my X3 actually existed and was working as advertised, I drove around for the first month of ownership with a meter attached.

I used a Vector plug-in model, but any DVM will work.

see: http://www.amazon.com/Vector-VEC008-...5922679&sr=8-1

As delivered, the car's battery was in a fairly low state of charge, so it took almost a week before the BER system started "cycling". Once the battery became almost fully charged, I would see the following:

1. Normal charging at around 13.6 to 14.0 volts for the first few miles after starting.

2. After a few miles, the charging voltage drops to 13.2 or 13.3 during steady cruising, indicating a low load, low (trickle charge) situation.

3. At throttle lift off or brake application, the voltage shoots up to 14.8 volts, indicating a maximum charge rate and high alternator load. This continues as the car slows down and the transmission downshifts through each gear to keep the engine speed above 1200 rpm minimum so that the alternator can develop maximum output.

4. Once the car is almost stopped, the torque converter unlocks and the engine drops to a low idle. The charge voltage then drops back to 13.2 indicating a light load on the engine.

Although there is some "up front" cost, it does certainly save energy, and considering the cost of fuel, is probably something that all but the smallest vehicles will eventually adopt.

[LEDZEP]

Lotus7


Years ago, we had a forum member called E90Fleet. He was so knowledgeable about BMWs it was frightening. He probably made close to 10,000 posts in his career and not a single one was ever off topic or 'banter'. He was quite a gentleman, wise, and kind.

You sir, remind me of him. E90Fleet is sorely missed, but perhaps a new hope emerges... as was foretold by the prophets...


Me, I just make wise cracks and occasionally offer some information.

[Shaw]

Originally Posted by LEDZEP

Lotus7


Years ago, we had a forum member called E90Fleet. He was so knowledgeable about BMWs it was frightening. He probably made close to 10,000 posts in his career and not a single one was ever off topic or 'banter'. He was quite a gentleman, wise, and kind.

You sir, remind me of him. E90Fleet is sorely missed, but perhaps a new hope emerges... as was foretold by the prophets...


Me, I just make wise cracks and occasionally offer some information.

well, at least you offer wise occasionally... I normally only keep cracking!!!!

[Shaw]

excellent info by Lotus 7 indeed!!!!
thx

[Lotus7]

Gee guys, thanks for the kind words. The beauty of forums like this is the amount of information that can be shared. I've learned a lot here and try to contribute when I have something that I feel might help. Occasionally, I do get slightly frustrated when I see a topic being re-introduced that has been discussed in some detail previously.

Often, these threads take on a life of their own and evolve into something far from the original starter's topic. I'm as guilty as anyone in contributing to these "topic shifts" and although a cardinal rule of Internet discussion forums is always "keep it on topic"; it's inevitable these evolutionary shifts happen.

So, to keep this thread on topic, I’ll mention that, in fact, the BMW BER system, and most of my comments this time around have been posted before in an obscure thread called “KERS failure warning”. (For those who don’t follow Formula 1, “KERS” means Kinetic Energy Recovery System(s)) and can be used in 2011 spec F1 racing cars for extra passing power boosts.

see: http://x3.xbimmers.com/forums/showth...&highlight=BER

Post No. 8 in that thread titled “More than you every wanted to know about BERs” includes even more detail than I’ve mentioned here. I still have mixed feelings about the BMW implantation of BERS. It does save some fuel, but it also increases the long term cost of ownership at purchase and at battery replacement time.

Enjoy all the hi-tech goodies in your X3 It's a brave new world out there.

[sfax]

Originally Posted by LEDZEP

Lotus7


Years ago, we had a forum member called E90Fleet. He was so knowledgeable about BMWs it was frightening. He probably made close to 10,000 posts in his career and not a single one was ever off topic or 'banter'. He was quite a gentleman, wise, and kind.

You sir, remind me of him. E90Fleet is sorely missed, but perhaps a new hope emerges... as was foretold by the prophets...


Me, I just make wise cracks and occasionally offer some information.

+1 The second coming of E90Fleet (in a Lotus)