i3 EV Range Inadequate for US cities, Rex Thwarted

[Nu2ecar]

My girlfriend accuses me of not wanted to leave my postcode, so I'm the poster boy for an urban car. My average annual mileage is 8K. I calculate my daily average is only 24 miles - I fly out of town a lot. But 20 miles is a short trip within San Diego city, which must be 60 miles or more North to South. I think I need a real-life range of 80 miles.

The Rex didn't appeal- I don't want to lose performance entailed by the weight gain, but I would have accepted it. Due regulations, in the US the Rex will only kick in when the battery is down to 5%. Then the car will be powered almost solely by it's motorbike engine of 34 hp - dangerously under-powered in my opinion. That's a deal-killer for me. In California, an i3 with Rex won't qualify for the white HOV lane. That is likely the coup de grace kill it for anyone still standing. It's a shame the i3 has been compromised worldwide for the sake of the US market, where I now think it will flop.

I'd rather have an i3 than a Tesla. A nippy little easy-parking car, a scratch on which wouldn't move me to tears, would be fun. I'm going to monitor my drive-miles for the next month or so, but I don't think the i3 will make the cut.

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[AndyW]

AIUI, the 34hp engine charges the battery constantly (once it's turned on) whether you're accelerating or decelerating, so it's perfectly adequate in most conditions to keep the battery charged enough to run the 170hp motor. It's not like you suddenly only have 34hp under your right foot.

 

[Jeremy]

Yes - but when I drove on a motorway, starting with 16%, it varied from 12-16% depending on gradient and whether I was accelerating past trucks etc.

I would be nervous with only 5% reserve I think - in view of what happened to the Telegraph journalist who had it shut down to a sudden crawl.

 

[Bunter]

I would think that the restriction that BMW build into US REx variants would be easy to programme back to the EU version. I am not a programmer but there's surely this sort of thing is pretty trivial?

Bill

 

[TomMoloughney]

The 5% threshold is only for US cars. The i3's shipped to other countries with the range extender do have the ability to have the REx manually turned on by the driver once the state of charge dips below 80%. FWIW, the REx, even at the 5% threshold is more than capable for just about any duty called upon. If the driver understands how it works and keeps an eye on their speed they will have no problem. The Telegraph chap wanted to see what happens when you push the car beyond it's capabilities. You can certainly overwhelm it if you continue to drive above the speed limit up long steep upgrades. However as long as you drive reasonably when you are using the REx - which shouldn't be often, you can use it for just about anything, even driving hundreds of miles at highway speeds if you choose to.

 

[Lemonypye]

The 5% threshold is only for US cars. The i3's shipped to other countries with the range extender do have the ability to have the REx manually turned on by the driver once the state of charge dips below 80%.

Hi Tom,

Just for clarity, the UK REx, allows you to maintain charge once you hit 75% SOC.

Regards
Chris

 

[TomMoloughney]

The 5% threshold is only for US cars. The i3's shipped to other countries with the range extender do have the ability to have the REx manually turned on by the driver once the state of charge dips below 80%.

Hi Tom,

Just for clarity, the UK REx, allows you to maintain charge once you hit 75% SOC.

Regards
Chris

Thanks Chris. The earlier prototypes had software that allowed it to be activated once it dropped below 80%. So I guess for the production version they lowered it to 75%, thats good to know.

 

[jcal0820]

Since test driving (the BEV version) at the L.A. Auto Show a few months back, I've become highly interested in the i3 & keeping close track of it. The way I understand it, for the U.S. release, the REx equipped models can only engage the 'generator' when SOC reaches below 5%, as already disclosed in this forum. Apparently, this was done to comply with CARB and the hope of getting the coveted 'WHITE' Sticker for California HOV lane access. However, now that we know that the REx WON'T qualify for the WHITE sticker (BEV), but for the much limited in supply Green sticker (PHEVs), can't BMW now just re-program the U.S. spec REx's to the Euro version, which allows the driver to engage it at 75-80% and under? After all, minus well get the most out of it, to make it competitive with all the other PHEVs in the market, most noticeably the Volt. If BMW leaves as is, with the REx engaging at 5% and under only, they'll have a flood of dissatisfied customers, most of whom will end up limping along the far right lane with hazard lights on, which will ruin the i3's reputation, both BEVs and REx versions. Isn't it as simple as a software update?

 

[dennis]

Since test driving (the BEV version) at the L.A. Auto Show a few months back, I've become highly interested in the i3 & keeping close track of it. The way I understand it, for the U.S. release, the REx equipped models can only engage the 'generator' when SOC reaches below 5%, as already disclosed in this forum. Apparently, this was done to comply with CARB and the hope of getting the coveted 'WHITE' Sticker for California HOV lane access. However, now that we know that the REx WON'T qualify for the WHITE sticker (BEV), but for the much limited in supply Green sticker (PHEVs), can't BMW now just re-program the U.S. spec REx's to the Euro version, which allows the driver to engage it at 75-80% and under? After all, minus well get the most out of it, to make it competitive with all the other PHEVs in the market, most noticeably the Volt. If BMW leaves as is, with the REx engaging at 5% and under only, they'll have a flood of dissatisfied customers, most of whom will end up limping along the far right lane with hazard lights on, which will ruin the i3's reputation, both BEVs and REx versions. Isn't it as simple as a software update?

Well... There are 49 other states in the Union, plus DC, Guam, Puerto Rico, and the Virgin Islands to worry about too... So, the BEVx category still benefits our friends that follow CARB. Folks in NJ (the North American home of BMW and TomMoloughney) will be able to get an i3 REX with no sales tax because of the BEVx rules.

 

[jcal0820]

This was the first article I read about the i3 with REx...

http://www.telegraph.co.uk/motoring/car-manufacturers/bmw/10440292/BMW-i3-Range-Extender-review.html

Note what the reviewer stated when he experienced loss of performance:

"“It’s not a limp-home mode as such,” a BMW spokesman later told me, “but once the charge runs down to five or six per cent and the range extender cuts in, if you keep driving at 75-80mph it can’t maintain the charge.” Rather than damage the battery by running it completely flat, the i3 had restricted our performance.
What I should have done, it transpired, was engage the range extender when there was still 30-40 per cent charge in the battery."

...Unfortunately, in the U.S. destined version, you can't engage at 30 to 40 percent charge, or any level, it automatically does so only when below 5% capacity is reached.

 

[mabooker76]

I suppose it really depends on what 'restricted speed' means.

Only in SoCal could 70 mph be considered 'limping' - granted California drivers do drive fast...

I set my cruise control at 70-ish and use Eco mode in my Active E if I am concerned about range to/from a destination and generally do not have any problem on most freeways, though that does keep me out of the left lanes.

Some trip examples:
Altadena to Chatsworth over the mountains on the 210 for 80+ miles.
Altadena to Tustin in Orange County via 210, 57, 22 for 95+ miles (a 4 hour 110 charge at the destination).
Anything else in a 35+ mile radius regardless of freeway or topography - no sweat, maybe Eco mode.

Martin B.

 

[jcal0820]

Do you make regular trips from Altadena to Tustin/Chatsworth & back, on the Active E? On avg, how much range do you have left when you reach the destination?

 

[mabooker76]

Altadena to Tustin once or twice a month, once a week to Chatsworth. I am at the 'top' of Altadena so it is truly uphill to home, but I get back from Chatsworth with about 5-9 miles indicated left on the charge, depending on traffic. The actual distance states 82 miles. Half the trip back is 'downhill' so I do get some charge back. I have the 220 charger at home.

I have 'missed' getting home from Tustin once. I was able to roll into a gas station a couple of miles from home and trickle charge for about 30 minutes. Generated an interesting scene as I was 'filling' up for free versus the people at the pumps...

I had a discussion a while back with BMW i management that US cities would be different from Europe - more spread out, and especially in LA, you do take 80+ mph freeways routinely to get around. Unlike Amsterdam, Munich etc. where you legitimately want to stay off the 100 mph Autobahns.

With the electric range somewhat less, and the fact that 'typical' speeds would draw down the charge faster, I am contemplating the REx.

Martin B.

 

[jcal0820]

What kind of additional maintenance would be required on the REx? I'm assuming nothing more than what is needed for a BMW 2 cylinder bike?