REx now with more power - 28 kW

[ultraturtle]

I would simply suggest that any driver with a frequent need to climb long grades at high speed after depleting the traction battery would be better served with a vehicle designed to do that. The i3 REx is many things (including the 5th most efficient automobile available for sale on this planet), but it is certainly not that.

Horses for courses.

 

[stumbledotcom]

Completely agree, ultraturtle. Second month of ownership and I remain delighted with my i3. Have already convinced a friend to buy one, even. But continue to be mystified by the distinct minority on this site that don't seem to get that the i3, either BEV or REx, is first and foremost a city car. I'd go so far as to say that if the majority of my miles were at highway speeds, 55mph or above, I would not have bought an i3.

 

[jadnashuanh]

It's not like BMW claims the i3 is a replacement for a generic ICE vehicle! It is what it is - a nimble, compact city car with some style (obviously, not to everyone's liking!). And, while you could use a spoon to dig a ditch, it isn't the right tool for the job, and an i3 isn't designed for a long trip or extended high-speed drives.

I picked up my new i3 this afternoon, and I'm probably an ideal candidate for the thing...90% of my trips are short, in town. I expect the majority of my use with be with the i3, but I have an ICE for those occasions when it isn't adequate. It has enough guts to hold its own at anything approaching legal speeds in the USA. I look forward to a long time of (hopefully) uneventful use of the thing. Only time will tell.

Now, when the winter tires become available later this year, I'll pick up a set and expect it to be fine for use here in NH, at least for running around town. My driveway is quite steep and long, otherwise, I'd probably consider sticking with the stock tires during the winter.

 

[surfingslovak]

I'm not suggesting that the i3 was an SUV, and that it should be used in that manner. And I certainly don't need to be reminded that it's one of the most efficient vehicles on the planet. It's something I predicted in the months leading up to its market launch. That said, BMW could have a marketing and potentially a legal challenge on their hands, if customers end up using the vehicle, within reason, for use cases that it was not tailored to, and the i3 grossly failed to deliver on their expectations.

This alone could be a compelling reason to increase the power output of the range extender a bit. The standard recommendation in Europe has been to engage the hold mode early, when anyone complained about the performance of the vehicle on hill-climbs. This mode does not exist in the US, courtesy of CARB regulation.

We will have to see how the i3 will do in the field, and how the car buying public will react to the REx, which is a completely novel concept on the car market. GM steered clear of a similar solution, because of concerns about its acceptance by mainstream consumers. I participated in numerous heated debates among early LEAF and Volt owners. It's easy to forget that what might be important to an engineer, might not matter much to the customer, who might have a completely different view and expectation of the product.

We have already witnessed early owners claim that the i3 should be able to handle the hills around LA, since they are an extension of the metropolitan area, and they need to cross them sometimes. I had a potential ActiveE lessee, a CEO of an electric drivetrain company, ask me if she could drive the car from SF to Tahoe on weekends. Many city dwellers apparently want to do that around here. They will surely expect the same thing of the i3. What are you going to tell them? And more importantly, what will happen if they undertook such a trip, against better judgement, and the vehicle failed them spectacularly?

It's better to defuse such situations upfront, and without watering down the overall concept and design the car, try to accommodate these scenarios by upping the power output of the range extender. Wouldn't you agree?

 

[electricvirgin]

It is worth noting that i3's in the US are slightly compromised by not having control of when the range extender operates. European cars can 'force' it on even when battery level is high, useful if you know you need to go on a long journey. That said its clearly not the car for frequent long trips.

 

[MikeS]

Better that the US customers look to their government as it seems to be the US laws that forced the change so its not BMW’s fault.

 

[mindmachine]

Better that the US customers look to their government as it seems to be the US laws that forced the change so its not BMW’s fault.

I disagree, BMW was thinking about themselves when they decide to cripple the Rex. Their greed for ZEV/CARB credits is what drove them to both cripple the Rex and the stupid gas tank size reduction too. BMW could have decided to sell the Rex version setup the way it is in Europe and received the lower credit for a PHEV.

So in my book BMW is screwing it's US customers that wanted the Rex, by reducing the capability for their own greedy reasons.

 

[electricvirgin]

I think the fact that speculation about if the Rex would comply with the regulations illustrates how complex and bureaucratic those rules have become. Nobody seemed to know for months one way or the other? If the regulators made the rules clear and transparent then everyone would be better off.

I have some sympathy for manufacturers being caught between the desire to create cars that best meet their customers desire to benefit from government subsidy on the one hand, and dealing with all the demands of government on the other.

Mind you my knowledge of the regs is sketchy at best so i could very well be wrong. However all my experience of govt grants/credits etc is that they are vague and open to numerous different interpretations.

 

[Stevei3]

Hi guys,

also don't forget that, IMHO, the whole ZEV/CARB/Co2 regulatory system is what makes cars like the i3 possible. Manufacturers wouldn't dream of investing this much money in products whose (short term-) profitability is as debatable as i3s. Agree about the US REx version being neutered a tad to much for comfort though...

Regards, Steven

 

[ultraturtle]

Let's not forget about costs and how those ZEV credits end up helping us end users. BMW is in business to make money. I doubt that they could turn a profit selling this incredibly expensive to manufacture vehicle at such low prices without accounting for the value of those CARB ZEV credits.

 

[MarkN]

Does/will the US REx have 28 kW of power? The BMW USA web site still lists 25 kW in the REx specifications. Given all the other ways the REx is crippled here I wouldn't be surprised if we don't.

I wish BMW USA would get their act together and say what their "Alternate Mobility Program" will be. If we end up buying an i3 REx we'll need an alternate vehicle for the couple of times a year that we'll be driving two cars into the mountains here in Colorado.

I feel bad for the Canadians who are getting the US spec REx. That's worse than getting it in a non-CARB state.

 

[surfingslovak]

The question of "mountain mode" is addressed on pages 52 and 53 in the 2012 AMENDMENTS TO THE ZERO EMISSION VEHICLE REGULATIONS. It might be a worthwhile read. I personally believe that these rules might be revised based on the learnings from the i3. In their present form, the only permissible workaround is a range extender with a higher power-output. I agree that BMW is trying to walk a fine line between low weight, high efficiency and reasonable cost. There is only so much they can change.



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[WasteZeroSF]

I am not sure what my kw is currently rated on my new Rex I bought today. After the REx kicked on flat highway it was not an issue to keep speeds of 70-75. As soon as we hit the Sierra foothills outside Sacramento on i-80 the car slowed to 50 mph. I immediately pulled off the freeway to let the engine charge the battery. The engine slowed down rpm's after exiting the freeway but stayed running and after 5 minutes of recharge, not much had changed in the SOC so I go back on to complete the last 3 miles up to the exit I needed to take. Then 10 or so miles later it happened again on a long sustained uphill. The REx is no match for hills unfortunately.

I my opinion, there is no way you could drive on the REx to Tahoe! I have to contact BMW to see what can be done. CEL came on after I fueled today and when I pulled in my driveway to charge I received a message to have BMW check the drivertrain. "it's ok to drive, but have the car checked".

Buyers remorse today, you bet! BMW help me!

 

[surfingslovak]

I am not sure what my kw is currently rated on my new Rex I bought today. After the REx kicked on flat highway it was not an issue to keep speeds of 70-75. As soon as we hit the Sierra foothills outside Sacramento on i-80 the car slowed to 50 mph. I immediately pulled off the freeway to let the engine charge the battery. The engine slowed down rpm's after exiting the freeway but stayed running and after 5 minutes of recharge, not much had changed in the SOC so I go back on to complete the last 3 miles up to the exit I needed to take. Then 10 or so miles later it happened again on a long sustained uphill. The REx is no match for hills unfortunately.

I my opinion, there is no way you could drive on the REx to Tahoe! I have to contact BMW to see what can be done. CEL came on after I fueled today and when I pulled in my driveway to charge I received a message to have BMW check the drivertrain. "it's ok to drive, but have the car checked".

Buyers remorse today, you bet! BMW help me!

Please be sure to join us on Facebook, and share your experience there as well!

 

[RJSATLBA]

I'm at something of a loss to understand why buyers of the US spec REx are surprised, disappointed and heading back to their dealers when it can't maintain 70-75 uphill on a freeway after the battery is down to the 5 or 6% level at which the REx kicks in. It is quite clear in the UK brochure that I was given by my dealer that the electric motor is 125kW and at the time the REx was shown as 27kW, so it's inevitable that the US REx will be unable to haul 1.4 tonnes plus bodies uphill at speed for long on the REx before the battery level becomes critical and it has to rely solely on the REx.

It isn't what it was designed for...

...unless of course the salesmen have been telling porkies and buyers have relied on them without doing their own basic fact finding.

 

[WasteZeroSF]

I'm at something of a loss to understand why buyers of the US spec REx are surprised, disappointed and heading back to their dealers when it can't maintain 70-75 uphill on a freeway after the battery is down to the 5 or 6% level at which the REx kicks in. It is quite clear in the UK brochure that I was given by my dealer that the electric motor is 125kW and at the time the REx was shown as 27kW, so it's inevitable that the US REx will be unable to haul 1.4 tonnes plus bodies uphill at speed for long on the REx before the battery level becomes critical and it has to rely solely on the REx.

It isn't what it was designed for...

...unless of course the salesmen have been telling porkies and buyers have relied on them without doing their own basic fact finding.

Not looking to maintain 70-75 up a hill, just a higher state of charge to make it at a decent speed (>55 mph).

 

[jadnashuanh]

This situation is a partial remnant of the limitation of when you can engage the REx in the USA...but, should not be a surprise to anyone. What would work, is the installation of some DC fast charging stations where you could quickly top off the batteries. The i3 is a city car...using it for longer-range travel is out of its design parameters. Yes, you can do it, but that operation can be compromised. IMHO, if your trip cannot be completed on the projected EV range, you should not take the car, or look for a charge point along the way and take the time hit. The REx is for those 'what-if' situations, where something unexpected happens, and you can (maybe limp) to a charge point without having to be stranded. Expecting otherwise, is outside of the design. It is not an ICE replacement with a quick energy refill system, where you can expect to be able to drive long distances with short stops to refuel and be able to maintain performance until you run out of fuel...in the i3, your fuel is the batteries, and the REx just cannot refill it fast enough under some conditions. The vehicle was designed that way. Think of the REx as sort of run-flat-tires...they allow you to continue and not stop right there, but they do not provide the same capabilities of one full of air.

This is a new concept and people do not understand it fully. TO make the REx large enough to propel the vehicle under all circumstances would mean more weight, bigger fuel tank, less EV range (because of the weight), or more batteries (which have their own penalties on overall range because of their weight and volume). The i3 is an elegant compromise of all of those parameters. Using it outside of the design goals, you will have issues. That you did not understand that prior to purchase (or choose to believe it) is unfortunate, but what part of Megacity car implies long-distance travel? It does what it was designed to do. BMW could have designed it to be a Volt competitor, but they didn't.

 

[Jeremy]

jadnas

That may be true for US - but I use my REx on trips of around 150 - 200 miles all the time.

I haven't used it in mountains yet - but keeping up highway speeds of up to 75mph is possible without depleting the battery on average terrain including modest hills.

I wouldn't risk it without at least 20% battery capacity to allow for overtaking & hills though.

I wouldn't be happy taking it much over 200 mile though - because filling it up with 2gallons every 60/70 mile is too tedious.

 

[Greatwhite]

I have the REX here in the SF Bay Area and commute 60 miles each way and use the REX side fairly regular, I have an incline coming home and I've only experienced once an issue where in REX mode it forced me to 53 mph, had my foot all the way down and it maintained 53 till I cleared the incline and was able to get some charge back in the battery going down the other side. What I found for me was that when the battery is depleted being in Eco Pro helps with REX as the demand on the battery is less than comfort mode and I've not had the issue since and notched up over 1200 miles on mine so far.

Stuart

 

[jadnashuanh]

I think the turn-on level for the REx in the USA is 18%...you cannot turn it on manually until it reaches that level. As a result, it ends up a different vehicle in North America.