Hybrid electric drivers drive more electric miles.

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janner

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A very interesting report appeared on Green Car Congress http://www.greencarcongress.com/2015/10/20151001-inl.html

Cars and drivers studied were mostly Leafs and Volts but overall 130 million miles and 6 million charging events. Some interesting conclusions.

Plug In EV private owners performed an average of more than 85% of charging at home. About half the project participants charged at home almost exclusively. Of those who charged away from home, the vast majority favored three or fewer away-from-home charging locations, and one or more of these locations was at work for some drivers.

Drivers of the Chevrolet Volt, an extended-range electric vehicle, tended to charge more frequently and to more fully deplete their vehicle’s battery than drivers of the Nissan LEAF BEV. This allowed the overall group of Volts studied to average only 6% fewer electric vehicle (EV) mode miles traveled as the LEAFs in the project, despite the LEAF’s much larger battery pack. INL suggested two reasons for this: first, Volt drivers tend to deplete their batteries fully, while LEAF drivers favored recharging with significant charge resident in their batteries. Second, Volt drivers plugged in more oftern than LEAF drivers

Extrapolating these conclusions to the i3 BEV and ReX one should find that ReX drivers drive more electric miles than BEV i3s - certainly we've had a few posting recently with electric % over 95% - because Rex drivers are prepared to run out of charge.

Whilst it does seem crazy to drag around the weight, cost and complexity of a Rex it appears that it enables more miles to be done electrically - counterintuitive maybe.

Interesting to have others views.
 
Fully agree.
We run the battery to depletion knowing that the Rex will get us home, often with the Rex coming on within a mile of home.
We'd never try this with a Bev.
 
And we do a regular 110 mile round trip, around 75 in electric mode, because the REx allows us to do this. Without the REx, it would be impossible.
 
This seems like a tough comparison to make, in general. This comparison would favor a BEV only when a trip is greater than the REx range but less than the BEV range. The comparison seems certain to favor a REx most of the time, but at the considerable costs of a higher initial price, additional complexity, additional maintenance, greater weight, less interior space in some cases, etc. To some of us, this trade-off just isn't compelling.

Certainly, those i3 REx owners who frequently drive farther than the range of an i3 BEV and who would not want to stop to charge a BEV sufficiently to complete their journey would drive a REx more electric miles than a BEV. When stopping to charge, some people think that this means stopping to charge to full, but even with an L2 charger, one might need to charge for only 15 minutes to add enough charge to complete one's journey.

However, those of us who rarely drive farther than AER of a REx would drive the same distance in a BEV. I do occasionally drive farther than the AER of a REx but less than the range of our BEV, so I likely drive more electric distance in our BEV than I would in a REx. We have once driven far enough to cause my wife to suffer from extreme range anxiety, so we stopped for 15 minutes at our BMW dealer to charge enough to make her comfortable that we could make it home without being stranded (I think we could have made it :)
 
I 'm driving a REx.
Currently overall 13290 km with 12784 km electric. This is 96.2 % electric.
I would never had done so many electric kms without the REx. Several trips would have been made with our ICE (Especially those trips that don't offer fast charging along the route!).
 
We're in a Rex.
I didn't take us long to realise that our best strategy is, as others have pointed out, to use the battery as long as possible and arrive home with an empty battery. The Rex completely cures range anxiety. If we want to do high speeds on a motorway, we sometimes switch Rex on at around 1/4 charge so the performance is not compromised if we "need" it. :twisted:
Living 35 miles from central London, we usually get there and back without the Rex starting up, but no charge left. I expect now winter's coming we might need the Rex for the last 2 or 3 miles.
My inner Scrooge also makes me wait until the sun rises over my solar PV array next morning before I recharge the battery!
:lol:
 
For me, making the decision for the REx over a BEV was the hardest part of the i3 purchase. In the end, the clincher was a statement from my wife (who uses the car more than me): "Basically, if you don't go for the Range Extender model, I'll be less likely to use it.".

Now, based on this, some might have rejoiced and ticked the BEV box on the ordering papers straight away, but I wanted to the i3 to become our main family transport. That's why I decided to spend £3k more on the REx.

Without it, I wouldn't have done any of my long distance journeys. Having said that, I still love the planning of journeys along motorways and rapid chargers. I simply make time for it and enjoy the (currently) free electrons provided by Ecotricity. That's probably why I ended up with over 95% of electric usage.

At the back of my mind, I still like to have gone for a BEV though and I wonder what range my next, future EV will be able to do.
 
I'll rethink the REx when I switch to an EV with more range. I've barely needed my REx so far, but winter is coming...
 
Winter range IS less than in the summer, especially in Wisconsin! But, assuming you plug in at home, if you get in the habit of setting a departure time with preconditioning, the range hit is not anywhere near as severe especially if at your destination, you can plug in again. Starting with a warm car and a warm battery pack makes a HUGE difference. Lots of shorter trips where it has to start from ambient can eat up a lot of watts unless you're the type that will forego cabin heat. The BEV is more efficient at this than the REx, since (at least in the USA) the BEV has a heat pump verses the REx requiring resistance heating. The BEV can be over 3-4x more efficient at heating than the REx as a result.
 
People who drive longer distances will be more likely to buy a Volt.

People with short commutes, and around-town errands will be the ones who buy a BEV in the first place. I am less likely to drain my battery to almost empty, because I don't drive much.

Some of the comments make it sound like the car dictates a person's driving behavior. I expect most people analyzed their driving behavior and chose the car that was appropriate for them...
 
I can only echo some of the sentiments of Rex owners on here, without the Rex option the main user (my OH) would not have been very comfortable with the BEV range under all circumstances Winter/Summer, as we have a 60 mile commute with a free to use CCS Rapid stop en route this has eliminated any range anxiety for us completely. The occasional longer distance trip over 100 miles means we don't have to stop for the last section of the journey which is a consideration as well.

Thus far with about 8% Rex usage I feel we made the right choice plus if the battery capacity diminishes over time, (10 year purchase for us) I can live with the lower ev range, or even consider a replacement battery pack depending on how well the rest of the running gear holds up.
 
I also deliberated about the choice between Rex and BEV.

Until recently i made a regular return journey of about 56 miles, well within the range of the car even in winter, however a few months ago the motorway slip road i use at the end of my journey was closed for unplanned maintenance. Had i chosen the BEV i would almost certainly have been stranded, and it was raining! As it was i ran the rex for the last mile or so and got home dry.

However in over 12000 miles i doubt more than 500 or so have been with the Rex in use, but those miles have made the difference between the car working (for me) and not being satisfactory.
 
I'll be setting off for another continental road trip this Sunday, Midlands (UK) to Amsterdam to Germany and back. Roundtrip around 900 miles, I'd say.

The charging network in the UK is good. NL's FastNed is great. But Belgium and -especially- France have larger CCS gaps and don't always tell me whether they're available or not.

Without the REx, I would probably get a plane to Amsterdam and then rent an ICE to go to Germany and back. Or I would do the whole trip in a Diesel.
 
While I find my i3 is comfortable for me running around, I do not find it overly comfortable on a longer trip, so even if it could go further, I would not want to, which is why I kept my other car. I realize not everyone can justify that, but for me, even if there were reliable CCS units along my route, it would not be my first choice for a longer road trip, REx or not. It's hard enough to find a L2 EVSE, let alone a CCS unit at places that would be convenient. WHere you live can make a huge difference. I'm hoping that sometime in the future, a serial hybrid, maybe the i5, would provide my EV running around town, and long distance travel in one vehicle, but only time will tell. In the interim, I've not been inconvenienced by my BEV, but being retired, I get to pick and choose not only the time, but the places I want to be. Everyone's situation is different. But, for many, the REx option is mainly for relieving anxiety. Because they have it, they make plans accordingly, but I do the same thing with my BEV and saved the cost and maintenance.
 
22 k pure electric miles and I optimized my long commute (103 miles each way) to run within 10 miles of an empty charge.

Not doing it anymore but I racked 1400 miles a week for 4+ months after I got the car in March.

I guess some of us like to live dangerously.
 
electricvirgin said:
Had i chosen the BEV i would almost certainly have been stranded, and it was raining! As it was i ran the rex for the last mile or so and got home dry.
The REX is heavier then the BEV, and gets less all-electric miles. On top of that, the ICE turns on when the charge is down to about 6%. That is, when the ICE turns on, a BEV on that exact same drive would be expected to have at least 10 miles of charge remaining. If you only needed the ICE for a few miles, the BEV would have handled that trip fine, leaving you with a few miles or more to spare.
 
i3Alan said:
electricvirgin said:
Had i chosen the BEV i would almost certainly have been stranded, and it was raining! As it was i ran the rex for the last mile or so and got home dry.
The REX is heavier then the BEV, and gets less all-electric miles. On top of that, the ICE turns on when the charge is down to about 6%. That is, when the ICE turns on, a BEV on that exact same drive would be expected to have at least 10 miles of charge remaining. If you only needed the ICE for a few miles, the BEV would have handled that trip fine, leaving you with a few miles or more to spare.

As my personal (and extreme) experience has shown the BEV is just fine for any range within the one indicated by the oboard range indicator which is quite accurate.

A little bit of planning goes a long way, but nothing that a 5 year couldn't grasp using the GPS (and you have to be 16 to drive!).
 
Perhaps hybrid drivers drive further because they actually need to. Their choice might be based on a longer commute than can be managed by a current BEV. The elephant in the room is that many buy REX because they have range anxiety based on anxiety, not fact.

With my BEV, I have all the range I need. If I had a REX I would be driving the same distances. I suspect most BEV drivers would be similar.

So, for me, this is a totally flawed discussion.
 
I drive my BEV as far as I have a need. If I'm quite sure I'll need to go further, I take my ICE, but at that point, at least to me, the ICE ends up being more comfortable. The i3 is by no means 'bad', I have no problems with it in the ranges it can handle, but if I'm near the end of the charge in one trip, it starts to be uncomfortable, at least to me. I have no regrets 'just' having the BEV, and specifically did not want another vehicle with spark plugs, antifreeze, oil changes, or a muffler. Not to count the lower efficiency or the lack of the heat pump.

If I had a hybrid and did not have an ICE as well as my BEV, yes, I'd be putting more miles on the vehicle since in addition to all of the running around town I use my BEV for now, I'd not be switching to my ICE for my occasional trips. If a plug-in hybrid comes out that has the room and features I want with the all EV range I desire, I'll probably trade both my cars in on one. I don't expect that to happen for at least a few more years.
 
I chose the REx model for a few reasons, the first being my dealer in MI only orders these models because of the lack of public charging stations and since we have harsh winters that cut down the range. The second reason is because I need to drive 100+ miles occasionally and, as mentioned, public charging stations are very limited or non existent in my area. While I could have purchased an older BEV model from a dealer farther away, I liked the idea of driving the car on longer trips to cut down on emissions instead of using my wife's SUV for these trips.

I commute to work 22 miles each way and some days run errands during my lunch hour. During a typical week I only have to charge at work, which provides 2 level 2 EVSEs, the other used by a coworker with a Volt. If I have an appointment after work (drive home, pick up daughter, drive to dentist for example) then I use the range extender. Some weekend trips require the range extender also.

I've driven over 2100 miles and have used about 2 gallons of gas, some of this was used for the maintenance mode. So I've only driven about 3% with the range extender but it's been worth every %. I'm sure as soon as the winter weather finally arrives in MI, that percentage will increase.

So long story short, if I had the BEV we would drive our SUV for some longer trips, not utilizing 80 miles of electric driving. For that reason, I don't think this is a flawed discussion.
 
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