I am new to commenting about and calculating battery range and efficiency. So feel free to kindly give me some corrections here! The weather was beautiful last Sunday. A great day for a drive! My wife and I loaded up to drive to her mom’s house 90 miles away. She was a good sport and helped me log data every 30 minutes of our drive - for example - our start data: Temp 55F Battery 100% GOM Range 103 miles in Green mode And then 30 minutes in we logged 59F, 87% batt, GOM 91 miles, 20 miles driven, avg speed 40.1, mi/kWh 4.3 Etc. DRIVING TOPOGRAPHY Our home town, Greenville, is located in the foothills of SC. Columbia is down in the midlands. The elevation drop from our house to the Electrify America charging station 86 miles away is 500 feet (I know, it’s not the Rockies). The roads and interstates are not flat...ever. You drive over a series of rolling hills the entire time down to Columbia. THE OUTBOUND DRIVE Green mode, 20 miles back roads, 66 miles interstate. ACC set to 72 the ENTIRE time. Never had to disable cruise until we exited the interstate. We arrived at the Electrify America station after 86.1 miles. GOM Range left = 27 miles, mi/kWh = 4.0, avg speed 58, battery left 27%. STATION REVIEW This station had good reviews on PlugShare: 7 CCS plugs and 1 CHAd on 4 dispensing units. We arrived with a Ford Mach E on dispenser #1. Cool! I parked next to it on dispenser #2 and was excited when I was able to start a high kW charging session...for the 5 minutes it lasted. It then ended my session. I started another. It lasted for 3 minutes and then stopped and ended my session. I tried the other plug on the same dispenser, and it lasted 2 minutes before deciding I had enough juice. So far I had received 5 kWh total into my battery and gone from 27% - 47% charge. I was getting a little stressed, and I had tried starting a session using my credit card, as well as swiping from my phone. Dispenser #3 next door was completely down. Dispenser #4 at the end was charging a Nissan Leaf. So that left me eye balling Mr. Ford Mach E’s session. He was at 91%, but I was not sure when he might leave. I went and asked him if his charging session was running okay and he nodded without saying anything. He had watched me having my problems on #2. I would have asked about his Ford, but, apparently, he was not a talker! I got back in the car. We sat there for about ten minutes and decided we would drive to my mother-in-law’s house and eat lunch before returning to try again. But just as I turned the car on, the Ford ended his session. I pulled one spot over and happily started using dispenser #1 - and it worked! Fast. We went from 47% to 98% in 29 minutes. In total, we took on 21 kWh and spent $9.41. I wasted a few extra dollars because I was curious how long it would take to get from 98% to 100%. Rookie mistake. We finally gave up after staring at 99% for too long. I give this station a poor rating because out of 7 CCS plugs, at least 4 of them were down. OUTBOUND REAL RANGE estimate 86.1 mi / 21 kWh = 4.1 mi/kWh 28.9 usable capacity - 21 = 7.9 kWh x 4.1 = 32.4 miles range remaining (vs GOM 27) A total of range of 118.5. THE RETURN TRIP Start values: 92% battery and GOM of 105 miles. Temp 73F. 90 mile trip. I went with Green mode again, and planted myself behind a truck going around 65 in the 70 zone. Then we watched the battery % tick down while watching our miles to home. When the miles to home was only 4 less than the estimated miles left, I switched to Green+ mode, which added 6 miles to the GOM. So we got a little warm for part of the trip with no A/C. But when we got closer to home I switched back to Green mode. RETURN REAL RANGE estimate My Chargepoint finished charging the Mini after 4 hours and indicated it used 29 kWh. So even with possible inefficiency of the EVSE and SE charging interface, it appears I was fairly close to using the entire usable capacity of the battery. We drove 91.7 miles. 91.7 / 29 kWh = 3.2 mi/kWh for the return trip. The GOM had 12 miles remaining and battery was showing 13%. SUMMARY: OUTBOUND: 4.1 mi/kWh, around 118 mile range RETURN: 3.2 mi/kWh, around 104 miles range Given that I drove more slowly on the return trip, the temp was 73F instead of 55F, and I did 30 minutes of Green+, I guess the elevation changes make a pretty big difference in battery usage. And there are no readily available charging stations (looking at PlugShare) between Columbia and Greenville, so no way for me to stop for a 15 minute top off. That return trip definitely gave me range anxiety. I will be less stressed to do the trip again once there are a few more reliable CCS chargers along the interstates - I’m talking to you, possible future Infrastructure Bill!
Oh - I forgot to mention - the car does turn heads. The charging station is on one side of a Wal Mart parking lot. Two different cars slowed down to rubber neck the SE (the Ford was gone by then), both of them drifting to the right into empty parking spaces, and both had to swerve back into the lane to avoid hitting a parked car!
Thanks for the detail. I'm definitely going to take my SE when I get it on a road trip but that has been my worry is charger reliability. I've never had an issue in my Tesla Model 3 with a supercharger. I wonder what is causing these to frequently go down? Hope is it something they fix because that definitely would be a turn off for many people considering any EV.
Thanks for the report. I remember watching a YouTube video made in the UK, where the Mini gave them 15-20 miles more than the GOM predicted. I suspect that you had some extra reserve, and could have stayed in Green mode. The infrastructure has been improving rapidly over the past few years. It may actually accelerate now that 1) Democrats have control of the government and 2) more EVs on the roads create real demand. Last summer I drove my Bolt from upstate NY to Myrtle Beach and back. The route was well-covered with chargers. It would not have been nearly as easy even the summer before, and two years before, it would have been impossible.
Anecdotes seem to indicate Electrify America charge points have reliability issues, which is a shame since they're so attractive. And a good rule of thumb is if you're paying to charge, always stop when the rate drops (around 85% for the SE). That last 15% or so can take as long as the first 50%. I'm curious what kind of wheels you have? In those conditions I see much better range with my power spoke wheels – I've actually gotten close to 140 miles! (I'm still waiting for winter to end, alas.) I have found it's nerve-wracking the first time or two you hit the "danger zone" of less than 12 miles left, but unlike a gasoline-powered car there's much less guesswork as to when you'll run out, and I've come to the realization that if my destination is within the same number of miles as my battery's SoC there's no need to sweat the distance.
You could have had a headwind on the way back. Even a 15mph wind will make a huge difference in range. I've experienced this on a couple different road trips, where my efficiency in one direction on a given leg was drastically different than the opposite direction.
I'm running the Hankook evo3s. I was assuming the constant hills is what kept me from getting 'really good' range on the way down. But I'm not sure.
I was wondering about the wheels in addition to the tires. Some of the wheels are quite heavy, relatively speaking.
Glad to see honest reviews on this forum. Too often the EV fan boys paint everything in a nice rosy color when we clearly have a very long way to go. Sent from my iPhone using Tapatalk
Oh - sorry! Wheels, not tires. I have the 17" Scissor spokes. I'm not sure if I have seen weights for those posted.
Actually I just reread, it seems your efficiency was about the same in each direction. You used (100-27)=73% to go 86.1 miles, giving 118mi of range, and (91-13)=79% to go 91.7 miles, for about the same range (116mi) on the way back. Also if anyone is considering doing a trip that pushes up against the SE's range, I really recommend getting the A Better Route Planner app and a $30 bluetooth OBD dongle. The OBD adapter gives the car's real-time consumption info and battery % to the app, and it uses this data to update and display your expected battery % at the destination as you drive. It can reroute you to chargers or tell you to go slower if you're less efficient than expected. It really helps to alleviate range anxiety, since the GOM is less than accurate.
As nice-looking as they are (and they are really nice!), I suspect they're heavier and/or have more drag than the power spokes. That open design could be quite susceptible to headwinds. Too bad we can't easily have two different SEs travel the same route with different wheels to see any performance differences.
I believe MINI claims the Power Spoke rims are the lightest 17" rims they make. I'm sure they're the most aerodynamic, too.
Great recording of your story. I hope others offer similar stories when they can. FWIW, I'm now glad I didn't try to do my 400 mile road trip with my SE the day after I brought it home!
Yep, fizzit is correct - you got 4.08mi/kWh there, and 4.02mi/kWh back. The elevation change (ignoring efficiencies/losses) is about 0.62kWh (m.g.h / 3600000) which is about 2% of the battery, so assuming you gained on the way there, and lost on the way back, your figures completely add up. Goes to show how bad the GOM is, even when traveling in the worst case scenario (freeway). As Fizzit said, you probably had 24 miles left when you got home, not 12 as indicated. At least you know you can do it now It is amazing how long that last percent takes. It can take 10 minutes just to tick over to 100%! I've found the best compromise is about 95% - still quite quick to get there, and you only drop 5% range. Sounds like you had a fun day, and next time you know you can easily do the trip without worrying. One thing to remember when charging is that the car requires a bit of power to run the charging circuitry/heating/cooling, and charging efficiency. From my tests, I lose about 400W to this - so my 2.4kW charger only really supplies 2kW to the batteries. Using the energy supplied by the charger is useful to calculate the cost of the trip, but for driving efficiency (and hence range etc), you need to use kWh from the battery (eg. percent). PS. love the colour - BRG *is* MINI
@vader and @fizzit - thank you for explaining how this should have been calculated. I will use the battery % in the future for efficiency. Makes me feel a little better. That @#$ GOM causes unnecessary stress, but I understand they want to be cautious rather than aggressive in the estimates.
Apparently GOMs are a plague in many makes of EVs. The way I've learned to use my GOM is to compare what it says for miles against my SoC %. Assuming 1 mile per 1%, if the GOM is significantly higher than the %, I know I'm driving efficiently. If it's lower, I always know the weather conditions are the issue. I kind of have a game, see how many miles I can go before the GOM drops. Some days I'll drive over 10 miles before the GOM changes its value, again signifying efficiency.
I wish I could correct my original post now to provide the correct efficiency data, but, based on the new knowledge, I created this spreadsheet showing range and efficiency at the points where we logged miles and battery-% remaining. Not as bad as I thought for the return. But the charging station situation is still nerve racking.
True, and I always try to plan for a backup location for charging. Hopefully we'll see better infrastructure developed in the next couple of years, making this less of an issue. The big issue, I think, is public EVSEs are generally unattended so there's nobody on site to address any issues. Fueling stations almost always have attendants. A few things to ease road tripping anxiety: The MINI navigation display can be configured to show charge locations on the map I recommend the PlugShare app, it's a really reliable way to find and check the status of charge points I keep my Level 1 cable in the SE, there is always a 120V outlet somewhere for dire emergencies