SanSerif
Posts: 175
Joined: Mon Aug 05, 2013 11:09 am
Location: Southern UK, EU.

Re: REx is not a panacea!

Sun May 18, 2014 2:07 pm

Hmm. One thing I've learned over the past 3 months of EV-ing is that maths and logic don't actually fare very well when talking about range. But the figures and hypotheticals don't stack up against my real life experience.

I've had almost 160 motorway miles from one charge and one tank. OK, it wasn't sub-zero[1] but it wasn't warm either - and the car was 4-up plus luggage. And I've done the trip twice so it wasn't a fluke!

On a day-to-day level, I find the REx gets very, very rarely used. But it does mean that I'm happy to arrive home with 5 miles of battery left. So there's some sort of virtual benefit there.

Overall, I think the REx is a marvellous solution to the cost and volume limitations of batteries. It means I don't need a second car (or the hassle of hiring one). It means I get instant on the road "charging" on long trips and don't have to sweat a dubious public charging network. Altogether, well worth £3k (or whatever it was).

[1] And if sub-zero kills the case for the REx, then surely it double kills it for the raw EV?

Plug
Posts: 259
Joined: Fri Aug 02, 2013 1:17 pm
Location: UK

Re: REx is not a panacea!

Sun May 18, 2014 10:58 pm

Well said San-Serif.
SanSerif wrote:the figures and hypotheticals don't stack up against my real life experience.
It's quite easy to think all sorts of things whilst you wait for your car (I remember some daft threads here discussing the REx a few months ago, before any of us had even driven an i3) but some of these guys should come back and visit these threads after they've owned their car for a while, they might find their opinion has completely changed.

amateurish
Posts: 102
Joined: Mon Dec 16, 2013 9:10 am
Location: MK, UK

Re: REx is not a panacea!

Mon May 19, 2014 12:33 am

I'm sure that others have found that the better weather here in the UK has really improved range. On my 58 mile commute into work, I managed to use only 58% of my battery today (REx). My journey is 60% dual carriageway travelling at 70mph where traffic allows, and 40% A roads travelling at 50-60 mph. I'm not sure what consumption a BEV would have seen in the same conditions, but I do think that the OP is being much too pessimistic about the impact of REx on range.

fenlander
Posts: 22
Joined: Tue Mar 18, 2014 10:02 am

Re: REx is not a panacea!

Mon May 19, 2014 1:12 am

Having gone from a Leaf to an i3 Rex I can't imagine ever going back to a short range EV like the i3 BEV.

The Rex makes long journeys possible, you just keep filling up the tank. It's really not that much hassle to stop and fill up a few times on a long journey.

In day to day use I also find that I am driving many more pure-EV miles than I did in the Leaf. Why? Because you get to gamble more without any of the downside - rather than switch to an ICE car you can throw the dice in a Rex and take that trip at the end of the day which is on the edge of remaining range. With the Leaf I couldn't do that. I'm happy to trade a few percent of efficiency for that increase in overall EV miles.

Plug
Posts: 259
Joined: Fri Aug 02, 2013 1:17 pm
Location: UK

Re: REx is not a panacea!

Mon May 19, 2014 1:36 am

fenlander wrote:In day to day use I also find that I am driving many more pure-EV miles than I did in the Leaf. Why? Because you get to gamble more without any of the downside - rather than switch to an ICE car you can throw the dice in a Rex and take that trip at the end of the day which is on the edge of remaining range. With the Leaf I couldn't do that. I'm happy to trade a few percent of efficiency for that increase in overall EV miles.
That's something that I hadn't really appreciated before getting my car but I do now. For example, at the weekend I went shopping, I knew the car park had 32A chargers but I'd never been before so didn't know if I'd have the right card. I deliberately didn't bother charging the night before so I arrived with 8 miles range left, my card worked and I departed later with a fully charged battery. That's not something I'd have risked doing with the BEV. A minor perk but a nice one :)

Surge
Posts: 256
Joined: Fri Apr 25, 2014 5:11 pm
Location: Toronto, ON

Re: REx is not a panacea!

Mon May 19, 2014 6:27 am

amateurish wrote:I'm sure that others have found that the better weather here in the UK has really improved range. On my 58 mile commute into work, I managed to use only 58% of my battery today (REx). My journey is 60% dual carriageway travelling at 70mph where traffic allows, and 40% A roads travelling at 50-60 mph. I'm not sure what consumption a BEV would have seen in the same conditions, but I do think that the OP is being much too pessimistic about the impact of REx on range.
That's great. And I think the important point here is that driving route and style affect range a great deal (stating the obvious here!).
But whatever your range in the REx, you will get at least 5% if not 15% in winter conditions with the BEV.
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Surge
Posts: 256
Joined: Fri Apr 25, 2014 5:11 pm
Location: Toronto, ON

Re: REx is not a panacea!

Mon May 19, 2014 6:32 am

fenlander wrote:Having gone from a Leaf to an i3 Rex I can't imagine ever going back to a short range EV like the i3 BEV.

The Rex makes long journeys possible, you just keep filling up the tank. It's really not that much hassle to stop and fill up a few times on a long journey.

In day to day use I also find that I am driving many more pure-EV miles than I did in the Leaf. Why? Because you get to gamble more without any of the downside - rather than switch to an ICE car you can throw the dice in a Rex and take that trip at the end of the day which is on the edge of remaining range. With the Leaf I couldn't do that. I'm happy to trade a few percent of efficiency for that increase in overall EV miles.
Great points indeed.
If I got the REx, I would probably custom fabricate a spare gas tank to fit in the front trunk. Based on volume calculations, you should be able to get about 22L of fuel, enough for 2.5 refills of the gas tank.

The only "problem" is that at 120 kph, you would have to stop every 45 minutes to refuel.
NOT- Soon to be ordered:
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Surge
Posts: 256
Joined: Fri Apr 25, 2014 5:11 pm
Location: Toronto, ON

Re: REx is not a panacea!

Mon May 19, 2014 6:39 am

Surge wrote:
fdl1409 wrote: Yes, the last 6.5% the REx will start. But still, those 6.5% are available und you can and will use them if the fuel runs dry.
Thinking more about this - I'm not sure. In Europe, yes, but in the US/Canada, until we figure out if we can turn the REx on/off manually; it may not be possible to use the last 6.5%.
Why? Well what happens if the car is continually trying to start the gas engine? Hopefully it's smart enough to detect there's no fuel in the tank.
I bet most REx owners would never risk running the fuel tank dry (as that carries its own issues), and so that last 6.5% of the battery will indeed never be used (again, I'm referring to non-European cars).

Such a life, there are always downsides! :?
NOT- Soon to be ordered:
i3 • Lodge interior • Tech package • DC fast charge • gray or white

amateurish
Posts: 102
Joined: Mon Dec 16, 2013 9:10 am
Location: MK, UK

Re: REx is not a panacea!

Mon May 19, 2014 6:49 am

I'm pretty sure that the REx has been designed so that you can run it to "empty" and it will switch seamlessly back to battery. So it should be perfectly possible to use the final 5% of charge.

MikeS
Posts: 713
Joined: Thu Jan 16, 2014 8:29 am
Location: Brighton UK

Re: REx is not a panacea!

Mon May 19, 2014 7:17 am

Someone on here posted that that did run out of fuel in the REX (by accident) and the car switched seamlessly back to battery.
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