jadnashuanh
Posts: 5069
Joined: Thu May 22, 2014 2:07 pm
Location: Nashua, NH USA

Re: What does your "miles to empty" show when full?

Sun Sep 13, 2020 1:16 pm

FWIW, on the REx, any heating for the cabin is via resistance heaters which can suck up a lot of energy...1w out of the battery = 1w of heating. On the BEV that has a heat pump, 1w out of the battery can produce as much as 3w of heat, so it's lots more efficient when heating unless it is too cold for the heat pump to work, then it falls back to the resistance heaters like in the REx.

In 2017, there might have been a few REx models with the smaller battery, but most of them have the larger one.
Jim DeBruycker
2011 535i x-drive GT, 2014 i3 BEV
Soon (hopefully!) A 2021 X5 45e will replace the above

sipabit
Posts: 192
Joined: Sun Mar 04, 2018 2:01 am
Contact: YouTube

Re: What does your "miles to empty" show when full?

Thu Sep 17, 2020 11:11 pm

Your GPS being on with a destination will also affect what your range displays. I have the low range i3 and i've seen it as low as 60's and as high as 110miles.
A fanatic of all things electric. Ridables like electric ice chests and stand up scooters I adore. Drones like DJI, I root for. I'm a fan of both, but nothing beats my love for my 2016 i3 Rex with Deka World. Shhh, don't tell my wife.

Arm
Posts: 46
Joined: Tue Jan 07, 2020 5:53 pm

Re: What does your "miles to empty" show when full?

Sun Sep 20, 2020 12:14 pm

I've a 2019 i3s Rex. I've seen as high has 230 miles after full charge...not including the Rex range.

Obviously I've not ever gotten that mileage on a full charge but I'm average 4.7 mi/kWh. So theoretically I should get 184 miles out of a full range.

I never run the car dry so I never know.

I do know however that my i3s is more efficient than both my 2017 Volt or 2014 Spark EV were.

I visit my folks on a regular basis where I average around 6.5 mi/kWh over a six mile route. Over that same route, my Volt and Spark only mustered 4.8 and 5.7 mi/kWh.


protonic wrote:
Wed Sep 09, 2020 3:51 pm
I just bought a 2017 REX model a couple of weeks ago. My range will show 141 miles when full (comfort mode). I'm surprised it is much more than the 114 advertised. I realize this is based on driving habits, so I'm curious what everyone else shows for range after a "fill up". I don't drive like a grandma so I'm curious why the range is longer. I would've expected it to be shorter than advertised based on my driving style. Do you find that the estimated miles is a close estimate to actual miles driven?

I'm guessing hard acceleration reduces the range, but what other things are factors? My daily routine consists of a 5 minute drive to the highway, another 15 minutes on the highway (all at speed limit during this pandemic), then another 5 min to my building. I would think this is a typical commute. I have zero knowledge of how these electric cars work with respect to "MPG's". Does 30 minutes at 30 miles per hour drain the same amount of battery as 30 minutes at 60 mph? Does 15 miles at 30 mph drain the same as 15 miles at 60 mph?

Also, just to avoid making another post, do you need to go into "park" before shutting off the i3 or can you just push the "off" button? I'm lazy. LOL.

protonic
Posts: 22
Joined: Mon Aug 31, 2020 7:52 pm

Re: What does your "miles to empty" show when full?

Sun Sep 20, 2020 12:22 pm

Well my last two fill-ups have shown 231 miles to empty. It must have adjusted the range from the previous owner. I'm guessing it will continue to drop...

Arm
Posts: 46
Joined: Tue Jan 07, 2020 5:53 pm

Re: What does your "miles to empty" show when full?

Sun Sep 20, 2020 12:22 pm

Also, a pretty easy rule of thumb for calculating MPG for an EV is to simply multiply 33.7 x your mi/kWh x 0.75 for losses and inefficiencies.

The sweet point for my car on the freeway is about 65 MPH. I average 5 mi/kWh on a flat road, constant speed.
protonic wrote:
Wed Sep 09, 2020 3:51 pm
I just bought a 2017 REX model a couple of weeks ago. My range will show 141 miles when full (comfort mode). I'm surprised it is much more than the 114 advertised. I realize this is based on driving habits, so I'm curious what everyone else shows for range after a "fill up". I don't drive like a grandma so I'm curious why the range is longer. I would've expected it to be shorter than advertised based on my driving style. Do you find that the estimated miles is a close estimate to actual miles driven?

I'm guessing hard acceleration reduces the range, but what other things are factors? My daily routine consists of a 5 minute drive to the highway, another 15 minutes on the highway (all at speed limit during this pandemic), then another 5 min to my building. I would think this is a typical commute. I have zero knowledge of how these electric cars work with respect to "MPG's". Does 30 minutes at 30 miles per hour drain the same amount of battery as 30 minutes at 60 mph? Does 15 miles at 30 mph drain the same as 15 miles at 60 mph?

Also, just to avoid making another post, do you need to go into "park" before shutting off the i3 or can you just push the "off" button? I'm lazy. LOL.

protonic
Posts: 22
Joined: Mon Aug 31, 2020 7:52 pm

Re: What does your "miles to empty" show when full?

Tue Sep 22, 2020 1:21 am

After a full charge, my distance to empty is now showing 109 miles. Quite a drop from 141. Both were set to comfort mode.

BL5
Posts: 26
Joined: Sun May 03, 2020 10:23 am

Re: What does your "miles to empty" show when full?

Tue Sep 22, 2020 6:56 am

Just purchased another i3, 2017 REx, the GOM says 121 at 100%. My 2015 REx says 72.

I've always wondered, is that estimate to 6% or 0%??
2015 White REx, loaded Tera, ACC
2017 White REx, every option
2018 Tesla P3

jadnashuanh
Posts: 5069
Joined: Thu May 22, 2014 2:07 pm
Location: Nashua, NH USA

Re: What does your "miles to empty" show when full?

Tue Sep 22, 2020 10:47 am

The range estimates are to the indicated zero point. And, the range to 'empty' is constantly being adjusted on a rolling average of the last 18-miles of use. So, unless you' are always driving the same route under the same conditions, it will often change. Say your trip starts out on country roads at lower speeds, but few stops then you get on the highway to your destination. Going one way, the country roads at lower speeds would seem to cause the range to creep up for a bit. But, after you get onto the highway and haul along with traffic (speed is the bigger killer of range), it would drop much more rapidly. I've had the range increase or remain the same after driving as much as 13-miles because the power use pattern was different than the previous use.

FWIW, this is no different than the range to empty you get on an ICE. I might see 300-miles to empty on my previous ICE, then part way into that use, get on the interstate, sit at a constant speed for hours, and it might rise up to 500-miles to empty. That's a huge difference, as it can be with an EV.

People get obsessed with the range on an EV since it takes much longer to fill it back up again, and there aren't as many places to do it as with an ICE. It is important, but you need to learn your vehicle. Bigger batteries in general either take up more space, or in the case of the i3 so far, become heavier...weight means range loss, so there's a magic point where bigger batteries can become a detriment as more weight means more tire wear, brake wear, heavier duty bearings, and suspension components, and that extra weight also affects range. Increased energy density is the big thing. A couple of kilos of hydrogen can drive a fuel cell vehicle maybe 300-miles, but where do you refill it from? Eventually, that may become the way we go with EVs, but it takes lots of energy to split water and compress the hydrogen, and until excess green energy is available, not likely to become widespread.

Throw in a large heating need, especially on the REx without the heat pump in the BEV, and then see what your cold weather range becomes!
Jim DeBruycker
2011 535i x-drive GT, 2014 i3 BEV
Soon (hopefully!) A 2021 X5 45e will replace the above

Return to “General / Main i3 Owners Forum”