66 mile round-trip commute Monday to Friday

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sliksal02

New member
Joined
Apr 22, 2016
Messages
4
Is the REx a viable option for me? It's primarily a highway commute, about 33 miles each way, with average speeds over the week of around 35 mph (but significant stretches of 70+ on the highway). There's chargers in the parking garage in my office. There's also chargers 3 blocks away at home (at the local civic center) but, and this is worrying me, my garage in my apartment building has no power sockets. I can't charge it at home. I could very easily leave the car at the civic center overnight, though. And I could get a full 6-8 hour charge at work. But I'm a little worried about weekends.

Does the REx make sense for me? I currently spend about $170 in gas alone per month.

P.S. this is Los Angeles driving on the 405, mostly.
 
I think a REx could be an option for you. The 66 mile roundtrip commute should be covered electrically alone, you might get some days where the REx would kick in (Highway driving too fast or lower outside temperatures... even in LA). I wouldn't go higher than 70 or 75 on the highway though. Over the weekend I would use the charger 3 blocks away. Maybe I would also get a foldable bike for the boot, to make the journey to get home/pick it up shorter. That's what I've done :)

But also consider if other people at your work might use the charger, which could mean you can't always get a full charge or use it at all. Those days you will require the REx, but that's what it is there for.

Hope this helps a little in your decision making.
 
IF you had home charging capability or knew that you'd have consistent access to the charges at work, you'd probably be fine without the Rex.

However, as a Rex owner, I'd go with the Rex simply to give you peace of mind on those days (especially the cooler ones) you need to run out to lunch or stop off for groceries on the way home.

Additionally, although charger are far more plentiful out west than back here in the east, its still nice to know that if you ever want to take a longer trip, you have the added insurance of the Rex.
 
I was in the exact same scenario as you.. i had 27 miles each way and no charger at home. I made the decision to go to REX and let me tell ya, thank god I did that... i probably needed the rex about once a week during the summer and more than that during the winter. it wasn't until i convinced my apartment building to let me pull wiring to get a charger in that I really stopped using the REX on a consistent basis.
 
The 2017 MY will be coming with a larger battery, estimates on range 100-110 miles, but that's still in the air. THey will start building them in July 2016. A REx would let you go much further, should you want to without the range anxiety, but it does cost more, requires more maintenance, and, with the 2017 MY's bigger battery pack (same physical size and weight), may no longer be necessary. If you were going to order one, you'd probably end up with a 2017 anyways, so take that into consideration. For the extra cost of the REx, and that it is slightly less efficient because of the extra weight you're carrying around all of the time, you could probably rent a vehicle if you really need to go further on occasion.
 
Thank you, lots of great info here.

The fold-up bike is a great idea!

Jim, unfortunately 2017 MY might be too far out for me. I'm also looking at the remaining 2015s, and hoping for steep discounts. (Any ideas on what I might be able to get off MSRP on a '15 REx?)
 
You should be fine to run on battery power for that commute. Even if the spot at your work was taken, you could drive home using the REx for a portion of the trip and then charge at the EVSE close to your apartment. The worst range I got on my commute, mostly highway, was around 55 miles in the winter. That's in Michigan with temps below 20 degrees F. Now that Spring is finally here my range is much better.

If you already have a bike with a quick release front tire, you can stow that in the back with the rear seats folded down. I frequently put my 29" mountain bike in the back of mine, handlebars towards the front. I have to move the passenger seat forward a bit but I have driven that way with a passenger and they still had leg room. I also put down a tarp to protect the interior. It takes a little negotiating to get the bike in and out but I'm glad I can still drive the EV on planned biking days.
 
Bottom Line: Don't do it.
You need a charger at home, or there is a lot of wasted time & inconvenience in your future.
Chargers outside your home cannot be relied on. Reality.

Pick a Chevy Volt, recently updated, lots of electric range (50 miles), and something much better than a weak BMW i3 rex 34-hp engine to back you up, for hundreds of miles when needed. Or a C-Max or Fusion hybrid, any of those. Many choices. I.E, the current Leaf has a 107 mile range, better anyway, or wait til the BMW i3 has 105 miles range (5 months away).
 
electrons said:
Bottom Line: Don't do it.
You need a charger at home, or there is a lot of wasted time & inconvenience in your future.
Chargers outside your home cannot be relied on. Reality.

Pick a Chevy Volt, recently updated, lots of electric range (50 miles), and something much better than a weak BMW i3 rex 34-hp engine to back you up, for hundreds of miles when needed. Or a C-Max or Fusion hybrid, any of those. Many choices. I.E, the current Leaf has a 107 mile range, better anyway, or wait til the BMW i3 has 105 miles range (5 months away).
While I agree this may add some wasted time and inconvenience I wouldn't consider the fact that he doesn't have an outlet in his apartment building (yet) a deal breaker. Since there is an EVSE at his work, 3 blocks away from his apartment, and the fact that CA has a good charging network, I think he could make this work. It will require some extra effort and some inconvenience but he should weigh these to the benefits. I rarely charge at home and don't have a good charging network in my area, but the REx has been a great solution for me.

I also wouldn't call 50 miles lots of electric range and the Leaf would be the worst option for his situation. At least the REx, which has a sufficient motor for charging the batteries when needed (not sure why you call it weak since it's sized for its function), would be a good back up.

Bottom line, he should weigh the cons of not having an outlet where he lives to the benefits of driving an EV. If the EVSEs at his work and near his apartment are regularly available, it may be worth the effort. I agree that a hybrid could be an alternative solution if the cons outweigh the pros.
 
brorob said:
Bottom line, he should weigh the cons of not having an outlet where he lives to the benefits of driving an EV. If the EVSEs at his work and near his apartment are regularly available, it may be worth the effort. I agree that a hybrid could be an alternative solution if the cons outweigh the pros.
I agree, he could make it work. It wouldn't be great to be on the 405, lanes away from the "slow" lane (if such a thing even exists on CA freeways), and have the battery depleted due to use of steady throttle in rex-mode, only to have the tiny 34-hp motor to maneuver the car through traffic with.

I do like the fact that the Rex engine is small, to save space & mass, yet, really(?), driving a car that can't get out of its own way is dangerous and shouldn't be legal on serious American highways. You can get 0-60 mph times of around 30 seconds sometimes with it. Totally unacceptable. Call it "You're-a-speed-bump Mode".

Trying to avoid these situations at all times requires luck, gamesmanship, and skill, ... and then fate & physics might just win anyway:

"“The i3 began to lose power without warning, subjecting the driver to more exposure in the oncoming lane,” Consumer Reports said. And while the car soon regained its power on coasting after the overtake — which Consumer Reports noted allowed the car time to replenish some of its battery pack — the test organisation said it was “disconcerting to say the least.”
According to the organisation, further testing revealed that prolonged use of the throttle with no speed variation or braking while the battery pack was reaching empty meant that acceleration dramatically suffered, increasing 0-60 mph times from the usual 7.5 seconds experienced in all-electric mode and 9 seconds in range-extending mode to anywhere from 27 to 40 seconds. For those taking notes, the Tata Nano, the world’s cheapest car, manages 0-60 mph in 30 seconds.
" -- https://transportevolved.com/2014/1...-acceleration-bmw-i3-rex-range-extended-mode/
 
Electrons, a lot of misinformation and FUD in your post. An i3 REx will not "lose power without warning" to drivers who understand how the REx functions and who are paying attention. There is no "luck, gamesmanship, and skill" required to avoid power loss. Full power is available as long as the battery's charge level is greater than ~2%. The charge level can be displayed on the instrument panel as a percentage, so a driver could take measures to prevent a power loss before it occurs. On flat highways like the 405, REx owners have reported being able to maintain 70 mph indefinitely without power loss. That's fast enough to "get out of its own way" even on the 405.

If one needs to maintain 70 mph up a significant incline like the Grapevine, a change in the North American i3 REx's configuration to European settings would be required (a.k.a., "coding"). Many i3 REx owners have done this and are not plagued by the fear scenarios that you have described.
 
The electric motor in the i3 is 170Hp...the REx is 34Hp...guess what, when the battery is essentially flat, you will have essentially the equivalent of a 34Hp engine keeping things going - about what an original Bug had, but more than a 2CV. It's usually more than enough to keep you going at speed unless there are other circumstances (really cold and heater on max, climbing a hill, trying to go really fast, etc.). As noted, though, you have to be pretty inattentive to ignore the status and warnings should you start to approach where the car will essentially go into battery protect mode. It does NOT do this without warning. You can think of it sort of like the low fuel indicator on an ICE...when the battery is really low, at least on the REx, you still can move, rather than the motor dying from fuel starvation like on an ICE. On a REx (or BEV), when it starts to warn you about battery charge, you have to either adjust your driving style or find a place to recharge/refuel, but it will keep going for awhile, and maybe a fairly long time, depending on how you're using it and the load applied.
 
Ok, this is about general REx usage now and not really about the OP's problem - who would be fine with the REx on the kind of commute he describes.

I drove 240mi to Leeds and back last weekend and used the REx for about 40% of that journey. There are plenty of free rapids along the M1 and it is easily possible to do this journey fully electric now, but I had the family with me and they generally want to get quickly to our destination. Once the REx had warmed up, I was able to maintain a motorway speed of 70mph without charging loss (give or take the odd motorway hill). Any speed above that and battery charge would go down slightly.

On long motorway journeys, I usually drive at 75mph with CC when fully electric, then enable the REx at about 25% SOC and drop the speed to 65mpg for about 5 mins, as it takes that long for it to warm up in my experience. Dropping to a lower speed prevents too much loss of charge in those 5 mins. After that, I go to a REx cruising speed of 70mph.

As a non-US owner, I obviously can enable the REx with SOC <=75%, so I would recommend the coding to US owners.
 
alohart said:
There is no "luck, gamesmanship, and skill" required to avoid power loss. Full power is available as long as the battery's charge level is greater than ~2%.
Good luck with that. The real world won't be as kind as you wish for. I'd suggest a reality check.
You say the Consumer Reports account I cited never happened? OK.... They would be surprised to learn they just dreamed it.

psquare said:
..........70mph without charging loss (give or take the odd motorway hill). Any speed above that and battery charge would go down slightly.............On long motorway journeys, I usually drive at 75mph with CC when fully electric, then enable the REx at about 25% SOC and drop the speed to 65mpg for about 5 mins, as it takes that long for it to warm up in my experience. Dropping to a lower speed prevents too much loss of charge in those 5 mins. After that, I go to a REx cruising speed of 70mph.
So you have to alter your speeds based on the pathetic 34 hp engine performance? Big problem. Hills happen, and you can't control how steep they are. And hope the wind is nice to you. Good luck. The 405 in LA, & other American freeways, require high speeds just to keep up a lot of the time.

jadnashuanh said:
....the REx is 34Hp...guess what, when the battery is essentially flat, you will have essentially the equivalent of a 34Hp engine keeping things going......
Thats the bottom line: 34 hp, is, well, 34 hp. Maybe people don't quite understand power, mass, acceleration, air/wind drag, etc.

------------------------------------------------------------------

I'll run it by some friends I know in the SAE to see if minimum performance standards (FMVSS in Fed-speak) are needed in the future to prevent the practical joke BMW is playing on American roads from recurring. NHTSA may already have a committee on it.
 
I have driven my Rex for extended periods on >100mi trips between NH and RI, and the comments are correct that you cannot maintain 80+mph cruising speeds without draining the battery. However, I can confirm that the Rex can traditionally keep up at 70mph.

Additionally, lets compare the alternative, the Rex's 34hp motor may not be able to keep you chugging along at 80mph once it kicks in, but you'll be able to go a heck of a lot farther with the Rex than without.
 
alohart said:
Electrons, a lot of misinformation and FUD in your post. An i3 REx will not "lose power without warning" to drivers who understand how the REx functions and who are paying attention. There is no "luck, gamesmanship, and skill" required to avoid power loss. Full power is available as long as the battery's charge level is greater than ~2%. The charge level can be displayed on the instrument panel as a percentage, so a driver could take measures to prevent a power loss before it occurs. On flat highways like the 405, REx owners have reported being able to maintain 70 mph indefinitely without power loss. That's fast enough to "get out of its own way" even on the 405.

If one needs to maintain 70 mph up a significant incline like the Grapevine, a change in the North American i3 REx's configuration to European settings would be required (a.k.a., "coding"). Many i3 REx owners have done this and are not plagued by the fear scenarios that you have described.


I agree, I purposely tried getting into the "low power" mode and it takes some effort with multiple warnings on the way before the car starts cutting power. I was going 80+ ( I found out that ACC maxes out at 85mph while turning off distance control lets you set it to 90mph)


As for OP, if you can find a stable charging location every night, or at work, then I'd say it would be perfect. I'm in the SGV area and I see people drop off their EV's at the metrolink station and pickup their cars the next day. If you're going to work during rush hour, you'd get much more miles per charge as well.

We've got a lot of Level 3 chargers in the LA area too so 0-80% is only a 30min charge. Level 1 chargers, the OUC that they give you are SLOW. IIRC ~20 hours to charge a depleted battery.
 
electrons said:
The real world won't be as kind as you wish for. I'd suggest a reality check.

Maybe people don't quite understand power, mass, acceleration, air/wind drag, etc.

Wow, looks like the real world certainly hasn't been kind to you.
 
This is one example that using metric system is easier :)

REX engine is 34 bhp or 25 kW
According to the range for speed article in bmwi3owner.com
at 100 km/h (or 62 mph), power consumption is 18.5 kWh/100km or 18.5 kW ;
at 120 km/h (or 74 mph), power consumption is 22.7 kWh/100km or 27.24 kW (22.7*1.2) .

On flat road without other loads (i.e. heater, air conditioning etc), the REX engine can keep i3 travelling at 70 mph (may be with a slight drain).

Yes, when travelling uphill the power consumption will go up, but then if you are doing round trip, the power consumption will drop when you come back downhill.

I have a BEV, so I just geek out on calculation, and have no way to verify. From my experience, the quoted power consumption rates are pretty conservative and can easily be achieved.
 
Bottom line, for many people, the BEV will suffice. If you regularly drive more than that can provide, the REx is an alternative. Driving style - HVAC use, lighting, speed, etc. WILL affect your mileage available, but if you understand and pay attention to the car's information, you should not run into issues with unintended consequences. If you expect it to operate like a conventional ICE which has no restrictions until it literally runs out of fuel, you are dreaming. It takes a certain mindset to drive an EV, or a hybrid, if you want to avoid surprises. The reward for this is much less expensive running costs verses an ICE or any hybrid available today. The REx is fairly efficient, but intentionally, not particularly powerful. It was a design consideration, and intended based on the expected use pattern for the vehicle - it WAS designed primarily for short-range, commuting. That people use it for longer trips is a tribute to the robustness of the design, but it has some restrictions. If you want a no restrictions vehicle that is as efficient, you'll have to wait, as neither the infrastructure nor battery density nor currently available vehicles is anywhere near what the i3 is today. Maybe the i5, whenever it shows up will be better suited for longer range, no compromises operation. Time will tell. In the meantime, I really like my BEV, as I did keep my ICE, and pick the best vehicle for my intended needs at the time. The REx could be an only car, but only if you can live with its restrictions. Best to understand and not be surprised. Like any tool, it is generally optimized for a certain task...the i3's optimization is not long-range trips. You can use pliers to loosen a bolt, but it often isn't the best tool for the job. Same with the i3 and long trips.
 
I think the OP will be fine. The 405 only has one sizable hill (going into and out of the San Fernando Valley), otherwise it is relatively flat. We have had our REx for a bit over 2 months now and I have purposely run out of charge in various situations to see how it performs. I now have complete trust in using the REx if needed as I really had to hammer it going up hills to get the reduced power warning. Last weekend, I drove it from Simi Valley to UCI (83.3 miles), mostly on ECO Pro, no AC on, made it with 12% left. I was going 65-70 the majority of the way. We charged to 100% on campus, and then drove back to Simi. REx did kick in on the way home, but I made it into Simi (about 77 miles on battery), this was with AC on the entire way. Like others have said, it requires a different mindset.

We are not coded yet, but I think in your position, with no charger at home, coding would give you additional peace of mind. Good luck in your decision!
 
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