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Discussion Starter · #1 · (Edited)
We've only had the Leaf for 300 miles but I'm intending to use it for a trip to Hampshire in a couple of weeks time. If range is anywhere near the claimed 150+ I should be able to recharge once in Oxford area and arrive at destination with plenty of reserve.

I have therefore been carefully monitoring performance over last couple of days and have saved all the readings at individual points on my journey in a spreadsheet which I've gone on to use to calculate some more useful ratios.
SpeakEV won't allow me to upload an .XLS file or even a .CSV version. The file attached to this topic is therefore a .TXT file but if you open it with Excel it ought to show my results (but not the actual calculation methods). For the full details, use the XLS version which is available here :-
http://www.khormaksarschool.org.uk/Leaf/Results from monitoring range & cons.xls

I've drawn several conclusions from this exercise :-
1. I'm fairly confident that a range of 150 miles can be achieved but even more comfortable with driving from Chesterfield to Oxford (120 miles), recharging then getting to Southampton (90 miles)
2. Sticking to approx. 65mph on motorways doesn't cause any problems with this. I'm not sure yet whether carrying two passengers & a fair amount of luggage might reduce range though it's still a fairly low percentage increase relative to car's unladen weight.
3. Engaging cruise control seemed to drop at least 10% off my calculated range
4. I can get some fantastic results in a journey that's all downhill. Alas, there aren't any long routes in UK that are all downhill (or even flat).

Another reason for including today's motorway legs was to check that the Ecotricity app on my (Android) phone works OK. It does - though I'm hoping to avoid having to buy electricity from them although even if I do, cost/mile whilst using it is still lower than my Volvo Diesel would manage

Comparing a few of my individual journey segments with the distances calculated by Google maps seems to indicate that car is overestimating distances (not surprising really - I'm pretty sure it overestimates speeds). A 6 mile journey according to trip figures is only 5.7 according to Google and a 33.3 mile journey from trip is only 32.7 according to Google. That's actually quite good news - if I really did manage the 164 mile range (144 travelled + 29 still available at end minus 9 miles added by a 4 minute charge) then I might even manage a journey that Google say will be 170 miles.
 

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I drive from home around the M25, M40, M42 up to Birmingham Airport. Trip distance 146 miles. I drove up the motorway at 62mph speed limited. Arrived with 7%.

Yesterday I drove 100 miles and arrived home with 32%. That included 6 stops for 5 jobs and a stop at Pease Pottage for a coffee. 7-10C. Internal temp 21C.
 

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I drive from home around the M25, M40, M42 up to Birmingham Airport. Trip distance 146 miles. I drove up the motorway at 62mph speed limited. Arrived with 7%.

Yesterday I drove 100 miles and arrived home with 32%. That included 6 stops for 5 jobs and a stop at Pease Pottage for a coffee. 7-10C. Internal temp 21C.
Bet that last Hill knocked a bit off your charge :D
 

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Discussion Starter · #4 · (Edited)
I recharged the car overnight and noticed following points :-

1. Car now announces its potential range to be 175miles. Really can't follow the logic behind that - it's obviously taken previous results into consideration when calculating that but I'm sure it's at least 4miles too optimistic.

2. Actual miles (or perhaps I should say odometer miles ?) per kWh (from supply meter) was 3.9. Using the method trip / 40 x use according to battery meter that suggests 3.95

3. 40kWh should therefore give a range of 158 miles; using my figure of 3.9 it would only be 156. OTOH, assuming odometer is over-reporting by a few percent it's probably only likely to be a range of 150 miles. That could improve slightly on a 'real' long trip since yesterday's average included mixed types of motoring but manual control of speed on motorway was slightly better than average. Provisional conclusion of all that is that 150miles is probably a realistic range so 120 miles to Oxford ought not to be a problem.
 

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Remember the 40kWh battery only has around ~38.5kWh of useable capacity, so you can’t simply multiply the miles/kWh by 40 as the car will never allow you to use 40kWh of capacity ...

David
 
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Discussion Starter · #6 ·
Remember the 40kWh battery only has around ~38.5kWh of useable capacity, so you can’t simply multiply the miles/kWh by 40 as the car will never allow you to use 40kWh of capacity ...

David
Thanks David, Good point.
That reduces my calculated range to just over 150 miles. Still well over the 120 I need to get to Oxford
 

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Discussion Starter · #7 ·
I repeated the exercise yesterday - except that I went a bit further up the motorway and didn't bother adding any charge.

Results broadly confirm previous run although there were a few anomalies:-
1. As near as possible, the first 32 miles should have been identical to previous run. In fact I calculated 4.38 miles/kWh on the first run but only 3.68 yesterday. Only difference I actually noticed was that on Friday I'd matched speed to several lorries and might have gained some air resistance advantages although I wasn't actually trying to drive very close to them.
2. After Woolley Edge services I switched the Eco button off. Partly to see what advantage(s) it offered (it's really only a way of persuading driver not to press too hard on accelerator) but also to see if the unwanted recuperative braking was reduced. On next journey segment of 24 miles (to A1M/A64 junction) I calculated 4.36miles/kWh but effect of lifting foot from pedal was just as marked. On return journey to Woolley Edge miles/kWh dropped back to 3.69 and was virtually same (3.68) between there and Woodall. Only thing I can really deduce from that is that it's perhaps not a very accurate method of calculation :D

But of course the real test is that during the day I covered 126.3 miles with battery dropping from 100% to 20% and predicted range at end was 39. T+R = 165 agrees reasonably well with scaling up with 127 x 100/80

Charging car back to 100% overnight used 32.7kWh; calculating that from battery meter suggested I'd only need 322kWh. I guess 2% charging losses is pretty good.

But bizarrely, having charged car back to 100%, it's now claiming that my range ought to be 194 miles ! I would have hoped that the car's calculated figure would bear some relationship to recent history but whatever algorithm Nissan are using seems to have inflated a sensible prediction by 30 miles (or 17%).

As I said earlier, my real interest is in whether I can get to Oxford for a recharge before carrying on down to Southampton and I'm now pretty confident that I can.
 

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Discussion Starter · #8 ·
But bizarrely, having charged car back to 100%, it's now claiming that my range ought to be 194 miles ! I would have hoped that the car's calculated figure would bear some relationship to recent history but whatever algorithm Nissan are using seems to have inflated a sensible prediction by 30 miles (or 17%).
Stop Press !
Having driven 14 miles this morning range now reads 170 miles i.e. 10 miles of 'range' just vanished :D
 

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I've found the GOM to be 10 - 15% optimistic in both the Leaf 24 and 40 Eric (with limited experience of the 40 so far).

I did North Cambs to Cheltenham and back (121 miles each way) on Saturday, 90% of which was on dual carriageways / motorway. It was 14 degrees C and dry and I didn't use the heater. Kept speed to an indicated 63mph on the way there and used 86% battery, did 68mph coming back and used 90%.

That suggests a range of 133 miles at 68mph and 140 miles at 63mph in those conditions. GOM before I set off was indicating 160 miles.

As you say I think your 120 mile stint should be no problem.
 

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Discussion Starter · #10 ·
As you say I think your 120 mile stint should be no problem.
Thanks Mark,

I presume you had a rapid charge in Cheltenham area ?

My journey is actually intended to be 120 miles driving, 40 mins rapid charge then a further 90 miles driving. Other threads in this section lead me to believe that just one rapid charge during a journey shouldn't be a problem.
 

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Sounds like it shouldn't be a problem going from Swansea to Gloucester services then (100 miles) before needing a top up charge. My Leaf is due end of May and Swansea to Evesham is the furthest I plan on going (parents) so with one stop this should be easy.
 

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Thanks Mark,

I presume you had a rapid charge in Cheltenham area ?

My journey is actually intended to be 120 miles driving, 40 mins rapid charge then a further 90 miles driving. Other threads in this section lead me to believe that just one rapid charge during a journey shouldn't be a problem.
I charged twice, once in Warwick on the way down after 82 miles and then in Evesham coming back after a further 58 miles. The last leg home was 102 miles, pretty much all at 68mph and used 78% battery. Your 120 + 90 should be fine at <70mph.
 

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Sounds like it shouldn't be a problem going from Swansea to Gloucester services then (100 miles) before needing a top up charge. My Leaf is due end of May and Swansea to Evesham is the furthest I plan on going (parents) so with one stop this should be easy.
Hey Thomas. Your journey from Swansea to Evesham should be do-able without a stop I reckon.

Depending on where exactly you are in Swansea and where you're going to in Evesham it's around 120 miles on the M4 / M5 motorways isn't it? Slightly shorter if you take the A40 / M50? I don't know the roads though.

After my trip this weekend I'd be more than happy to go for 120 miles non stop. There's rapid charging at The Valley retail park in Evesham (where I topped up) and the leisure centre too I think (that was my back up plan).

Once you've done a couple of longer trips you'll be more confident in how far you're happy to go.
 

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Don't forget that your MPG (well, eMPG) will get better when the tyres warm up. It is quite noticeable in my Leaf and the ICE - it starts to improve after 30-40 miles.
 

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I imagine that's down to tyre pressures increasing and rolling resistance decreasing with a rise in temperature? Mine started at 37psi and ended up at 41 or 42 after 100+ miles.

You could start with higher pressures if range was critical but there would be the safety element to consider if they got too high.
 

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And before I forget - I managed a personal record today. In and around Cambridge and on a mostly 40mph limited A14.

23.4 miles on exactly 10% battery used (started with 86%, clicked down from 77 to 76% at 23.4 miles).

If those trip and SOC meter readings are accurate that's an NEDC matching (or VERY nearly) 234 miles of range with a consumption of 6.5 miles per kWh.

I didn't set out on an eco run, just kept up with slow moving traffic and it was pretty chilly with no heating on but it shows what's possible in the right conditions. I reckon 250 miles might be on with warmer outside temps! Well there's a way to waste a day away . :D
 

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If you're running to such tight margins that starting tyre pressure determines whether you get to your destination or not, then you are doing something wrong.
Completely agree Jeff, I wouldn't do it myself. I just imagined it was probably one reason Orrery noticed a reduction in consumption after 30 - 40 miles.

Slowing down by a few mph I'm sure makes a much greater difference to eking out the miles, as I found out today (above).
 

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Hey Thomas. Your journey from Swansea to Evesham should be do-able without a stop I reckon.

Depending on where exactly you are in Swansea and where you're going to in Evesham it's around 120 miles on the M4 / M5 motorways isn't it? Slightly shorter if you take the A40 / M50? I don't know the roads though.

After my trip this weekend I'd be more than happy to go for 120 miles non stop. There's rapid charging at The Valley retail park in Evesham (where I topped up) and the leisure centre too I think (that was my back up plan).

Once you've done a couple of longer trips you'll be more confident in how far you're happy to go.
I will definitely try and do it in one trip but we have a little one and the wife loves Gloucester services so we would be stopping there regardless!
 

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Today was a short day.

I stuck to the speed limits rather than driving economically - 70mph indicated on ProPilot on the motorway and on the A & B roads where safe the speed limit, with quite a lot of foot to the floor acceleration.

Still ended up travelling 68 miles at 3.8mi/kWh and arrived home with 48%. If I had driven my old Leaf at the speed limits over this distance, I would have had to find somewhere to stop and charge.
 
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