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Discussion Starter #1
Getting used to this new car and i'm struggling a bit to get my head round the range and consumption.

Previous car was a Mercedes B250e. 28kwh usable, but not the most efficient of shapes and an EPA range of 85 miles. My commute is about 38miles, of which about 3/4 of it is free flowing motorway and i'm usually found in the outside lane doing 70 (on the GPS) The merc would use "about half" the battery getting to work on a good day, and approaching 70% used on the coldest winters days. Charger at work so no issues there.

My best ever journey managed about 90miles which was a fairly steady jaunt on some A roads, keeping to a maximum of 60 and generally being pretty gentle with the throttle. Not my favoured style, but i tried it to see what it would do.

So enter the LEAF 30.

EPA range is 100miles, so compared with the Merc i expected it would go a bit further. Even with similar capacity this makes some sense as its a lower, lighter car with a much more aerodynamic shape. Its showing 12 bars and Leafspy said (from memory) 95% SOH.

I've reset the average consumption meter a few times, and my driving seems to hover around 3.2-3.3 mi/kwh. Based on the LEAF 30 having 28 useable when new and 5% degredation, one imagines about 26.5kwh available now, and thus a range of about 85miles. When fully charged the car seems to like to suggest 100+ miles of range on the GOM.

I've had a few journeys recently however, where the cars really fell short of that.

At the weekend for instance i did 89 miles round trip. Almost all of it on the motorway. First leg was 43miles, started at 100%, arrived in the mid 40's. Did maybe 5 or 6 miles of town driving here and there. Then set off home. Drove to a nearby rapid, and charged from 39% to 63%, which ABRP said would be enough. Drove the 43miles home, which involved a small detour and i stuck to indicated 70 rather than "GPS 70" instead, and rolled into the driveway with the battery guage on ---%. That means 89 miles used all of the battery, plus the extra 25% top up from the charger.

That suggests nearer 2.6-2.7 miles per KWH? Yet the dashboard is still happily displaying 3.3mi/kwh.

Similarly last night, i drove to my folks 35miles away, having left with about 90% and arriving in the low 40's. Plugged in and charged to 63% with the granny. Drove home later and got in with low battery warning and 6% on the gauge. But again, 90 to 40, then 63 to 6, means i've used 107% to drive 70 miles?! Again that seems like its down in the 2.5-2.6 mi/kwh range, yet, again, the dashboard is showing 3.2. I've setup the App as well, and for yesterday its showing 77mi (the other 7 miles were some town driving in the morning which is why i set off with 90 and not 100%) and 3.2mi/kwh, and a total consumption of 23.82kwh.

These numbers dont really seem to add up?

Thoughts?
 

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Leaf30 struggles with efficiency when driving over 63mph.

Oh and it isn't as aerodynamic as you might think. It had a Cd of 0.32 if I'm not mistaken.

I don't know why you think Leaf would be more efficient than B250e (which is tesla tech underneath). We do sufficient miles in Leaf and average 4+ mile / KWh.

- Leaf 30 kWh
Sent from mobile phone so please mind the typos
 

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I guess you have checked tyre pressures, tracking, dragging brakes?

Can you get someone else to drive while you observe spydata?
 

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Remember the battery size Nissan advertises is total capacity. Usable capacity will be closer may be even less than your B-class.

As said, driving Leaf at high speed will see its range disappear. Try staying below 65 indicated speed?

I've never took much notice of the car's reported consumption or GOM. I just get a feel of its range and go by the % reading.
 

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Discussion Starter #5
Leaf30 struggles with efficiency when driving over 63mph.

Oh and it isn't as aerodynamic as you might think. It had a Cd of 0.32 if I'm not mistaken.

I don't know why you think Leaf would be more efficient than B250e (which is tesla tech underneath). We do sufficient miles in Leaf and average 4+ mile / KWh.

- Leaf 30 kWh
Sent from mobile phone so please mind the typos
Well both NEDC and EPA say the LEAF is more efficient than the B250e. And just looking at the cars, the B250e is tall with huge frontal area, the front end of its almost van like. even with the same Cd, the B250e will have more drag due to its larger frontal area. Its also several hundred kilos heavier.

I get that driving quickly uses more energy, its simple physics. I'm happy with that. If it were actually doing the reported 3.2mi/kwh i wouldnt have a problem. I dont expect to get 4mi/kwh out of it.

the issue is the disconnect between what the car is reporting its consuming and real world. The app reports my average yesterday was 3.2mi/kwh and says i used 24kwh in total but yet i had to charge it adding 20% or i'd never have made it home. Had it actually only used 24kwh it should have made the trip without charging at all, with energy to spare?
 

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Discussion Starter #6
I guess you have checked tyre pressures, tracking, dragging brakes?

Can you get someone else to drive while you observe spydata?
I've not checked tyre pressures, i assumed it has a TPMS and would be fine. But i will check them tonight.

Tracking i've been meaning to look into, the wheel is very slightly out of centre. Theres also a high speed vibration that feels like wheel balance or maybe a bent rim. A job for the weekend.

I will also get LeafSpy going while driving, maybe at the weekend when i can get the wife to drive.
 

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Discussion Starter #7
Remember the battery size Nissan advertises is total capacity. Usable capacity will be closer may be even less than your B-class.

As said, driving Leaf at high speed will see its range disappear. Try staying below 65 indicated speed?

I've never took much notice of the car's reported consumption or GOM. I just get a feel of its range and go by the % reading.
Agreed, and as i said in the first post, theres potentially only 26-27kwh available, which is likely less than the Merc had. It just feels like its using waay more than its reporting that its using. If it is indeed very inefficient at that speed and is using 2.6mi/kwh, then so be it. But its reporting 3.2, which "feels" more right. Economical drivers seem to get up into the 4's, so low 3's doing 70 seems to be about where things should lie?
 

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Agreed, and as i said in the first post, theres potentially only 26-27kwh available, which is likely less than the Merc had. It just feels like its using waay more than its reporting that its using. If it is indeed very inefficient at that speed and is using 2.6mi/kwh, then so be it. But its reporting 3.2, which "feels" more right. Economical drivers seem to get up into the 4's, so low 3's doing 70 seems to be about where things should lie?
Leaf's reporting is a bit pants to be honest.
I tend to look at overall power consumption reported vs consumption at the charger and miles achieved.

I've done 105 miles from fully charged to 14% SoC.
During summer, tyres can be pressurised upto 40 psi. Winter I tend to do it to 36 but we shall see this year.

Last month I did 1918 miles for 50kWh taking 87% charging efficiency. That comes to 3.83 miles / kWh from tap to road.

- Leaf 30 kWh
Sent from mobile phone so please mind the typos
 

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Discussion Starter #13
I've done 105 miles from fully charged to 14% SoC.
During summer, tyres can be pressurised upto 40 psi. Winter I tend to do it to 36 but we shall see this year.

Last month I did 1918 miles for 50kWh taking 87% charging efficiency. That comes to 3.83 miles / kWh from tap to road.
Clearly not doing 70mph though with those figures, unless my car is reeeeally broken :p
 

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Clearly not doing 70mph though with those figures, unless my car is reeeeally broken :p
Well if I'm driving I tend to stick to 63mph unless I'm in a hurry. My wife on the other hand clock's 70ish.

Over the summer she was doing 4x 24 mile journey and coming back with 10-14% SoC

- Leaf 30 kWh
Sent from mobile phone so please mind the typos
 

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When I bought my used 30kWh Acenta in June, I was unhappy with wandery steering on the motorway, my local tyres place tracked it (twice, eventually), did tyre pressures check, is spot on now. Also got them to activate car, click to "N" while 2 of us tried pushing/ pulling the car on their dead-level concrete floor, to check for any brake bind or wheel-bearing drag. Was nice and free, and have been achieving some reported 5+ miles per kWh over summer. So those checks def worth doing (good investment of £30, they didn't charge me 2nd time, as no adjustments needed.) Must add, that's in B mode and harnessing c50yrs of hyper-miling knowhow!
At some point soon, BEVs will start to come equipped with a 2-speed transmission, which will auto-shift at about 45mph, to combine low-speed responsiveness with longer range at cruise speeds. Cool! Recall it's ZF/Borg Warner who've developed it.
 
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