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Hybrid electric drivers drive more electric miles.

Thu Oct 01, 2015 5:48 am

A very interesting report appeared on Green Car Congress http://www.greencarcongress.com/2015/10 ... 1-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.
2015 i3 ReX Solar Orange, Loft interior world. BMW professional, 19" turbine-spoke 429 wheels, DC rapid charging, driving assistant plus.

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Re: Hybrid electric drivers drive more electric miles.

Thu Oct 01, 2015 6:43 am

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.

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Location: Suffolk, UK

Re: Hybrid electric drivers drive more electric miles.

Thu Oct 01, 2015 10:18 am

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.
i3 Capparis White; Winter package; Sunroof; LED lights; Ordered 30 May 2014; Delivered 17 October 2014.

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Re: Hybrid electric drivers drive more electric miles.

Thu Oct 01, 2015 2:06 pm

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 :)

2014 BMW i3 Arravani Grey, Giga World, Tech + Driving Assist, Parking Assist, DC Fast Charging, JuiceBox EVSE


Re: Hybrid electric drivers drive more electric miles.

Fri Oct 02, 2015 1:23 am

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!).

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Joined: Thu May 15, 2014 12:47 pm
Location: Stevenage, UK

Re: Hybrid electric drivers drive more electric miles.

Fri Oct 02, 2015 1:34 am

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!
Noteworthy cars I've owned previously: Lancia Aprilia ... 20kWh i3 Rex.

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Contact: Website

Re: Hybrid electric drivers drive more electric miles.

Fri Oct 02, 2015 2:11 am

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.

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Joined: Tue May 26, 2015 1:41 pm
Location: WI, USA

Re: Hybrid electric drivers drive more electric miles.

Fri Oct 02, 2015 9:01 am

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...
2017 REx - Platinum Silver - Deka

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Location: Nashua, NH USA

Re: Hybrid electric drivers drive more electric miles.

Sat Oct 03, 2015 4:15 pm

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.
Jim DeBruycker
2014 i3 BEV, 2021 X5 45e
(The i3 will be sold soon, <17K-miles, interested?)

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Location: Dallas, Texas

Re: Hybrid electric drivers drive more electric miles.

Thu Dec 03, 2015 10:48 am

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...
2014 i3 BEV
Bought used July 9, 2015

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