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Leafy day

As is always the case, I post some information on Twitter which in my stupidity I hope will answer some questions I’ve received about using electric cars.

This always results in one thing, a veritable torrent of new questions I hadn’t even considered.

I’m going to try and answer some.

Today I stopped in at Nissan’s Oxford dealership to use their fast charger. In 12 minutes this charged the Leaf with a two thirds charged battery to 100%. At home, you can use 240 volts at 13 amps. With a fast charger it’s 440 volts at 60 amps so it’s more juice more quickly.

I said that Nissan dealerships in the UK with fast charge units installed allow Leaf drivers to re-charge their cars there free, at present. They are offering this service to all Nissan leaf drivers, not just self important tossers like me.

I then posted a picture of the Leaf’s mileage estimate after I had charged it.

It said 108 miles. I should learn that I cannot explain the complexities of the Leaf’s range estimator with one picture and 140 characters.

What it’s saying is, if I continued to drive at around 15 mph, through the centre of Oxford in heavy traffic which I had just been doing, I would have been able to drive 108 miles.

The real world range of the Nissan Leaf with a fully charged battery on a warm day on average UK roads at the legal speed limit would be nearer 90 miles. If it’s very hilly, 85 miles, if you constantly break the speed limit and hammer the hell out of it, 65 miles.

If you charge the battery from utterly flat (in 18 months of electric car driving, I’ve never had an utterly flat battery) to 100%, it will cost about £2.50 in the daytime, and £1.50 at night. (off peak electricity is considerably cheaper per kilowatt hour.

I am having meters and lots of gubbins fitted at my house so I can give very accurate costs in the future, but for the time being, let’s be very generous and say £2.50, and lets be conservative on the range and say 85 miles.  That’s 3p a mile.

To compare apples with oranges, the per mile cost for a similar sized petrol car, 40 mpg, is 15p a mile, for diesel, 55 mpg is 11p a mile.

I want to add that I normally charge the car at night using off peak electricity at which point the per mile cost is under 2p per mile.

Will the batteries wear out if you keep re-charging them, like they do in lap tops.

I think the answer is eventually yes, their efficiency will drop over time, but not in a week or a month, all the estimates are that they will be good for 100,000 miles. They won't suddenly stop working, but the cars reliable range will slowly reduce. As this is new technology no one truly knows for sure but as an example Nissan are running a battery re-furbishment program. They‘re not going to chuck the old one away they are going to recycle everything they can, over 90% of the battery components can be re-used.

There’s lots more questions but I’ll shut up now. More soon.




Reader Comments (16)

My Ford Focus 1.6 diesel (which I'd argue is highly comparable) is not 15p per mile on fuel. As it averages 57mpg then that works out as 11p per mile (near enough). I Golf Blue Motion or the latest Focus 1.6 8 valve will do better. I think 15p for a well-driven, modern 5 door diesel hatchback is not typical.

That was what I averaged on a 13 mile commute run in mixed urban.trunk rode driving plus the odd shorter and much longer run.

Of course two-thirds of that is VAT and fuel duty so the actual costs of the fuel is more like 4p per mile (the VAT on electricity is low and there is not excise duty).

April 21, 2011 | Unregistered CommenterSteve Jones

Does the Leaf's range estimation need "calibration" like (for example) laptop battery meters?

April 21, 2011 | Unregistered CommenterChris Ridd

Hi Robert.
Just reading your latest post. You're certainly getting the facts and figures out there, which is what the great unwashed (like me) need to know. Have to say though, the juxtaposition image of the Leaf being 'charged through the nose' for free did make it look a little like Kryten and his groinal socket. Although if I recall correctly from DNA, that his recharge socket was located, shall we say, elsewhere...
Keep up the good work, you might convert this oil burning diehard yet...

April 21, 2011 | Unregistered Commenterdervheid

Hi there,

I am constantly fascinated by the range argument with electric cars, probably because I live deep in the countryside and am looking at getting a wind generator installed which up here does make some sense (I live in Northumberland.) The idea of driving into work all week for FREE* does, indeed, inspire me and a range of 100 miles is certainly sufficient for a week's driving.

But all these descriptions of the range assume 1 flat roads and 2 warm weather and make no indication of what happens if you run the radio and heater as well.

Compare this to the experience I had this winter where we got to minus 18 degrees up here and I was driving up hill and down dale in a small Mitzubishi colt with the heater on (it was -18!) and with the radio on (if you are miles from anywhere in a blizzard it's nice to have a human voice).

How would the Nissan leaf handle that? I assume that even with overnight charging it would struggle with the 40 mile round trip to work and back with power to spare (if I do crash or get stuck I want additional power to run the heater to keep me warm.)

This is the main issue, and I don't think they have it cracked yet. 100 miles is fine, in good weather, but you can't have just a "fair weather" car. You need one which will work in the worst weather you have ever seen, since you can hardly change it for a diesel when the weather gets bad.

Therefore giving a range update on the dash, I'm afraid, needs to assume -10 or worse and driving in hills. Only then can you really start to get an idea of the range capability of the car - if I had seen that and taken it at face value and gone driving this winter, I might have come unstuck v quickly!

*ok, not free, depreciation of wind generator as well, fair enough, but that cost is spread over the domestic usage as well, so we really aren't talking about a lot here.

April 21, 2011 | Unregistered Commenterlaughinggorilla

Well, now, there's a question. How does the heating work in a Leaf? Is it purely an electric heater or does it nick waste heat off the motor?

April 21, 2011 | Unregistered CommenterStephen Mackenzie

I've never got anywhere near the stated MPG out of my BMWs. Currently in a 520d which is meant to get about 48mpg (urban) and which has never shown more than 30mpg on the dash. Probably down to my driving style and the auto gearbox. Ah! The Leaf SHOULD be compared to an auto shouldn't it?

Anyway, my question is: does urban driving (stop, start) affect the range on an electric car like it does an ICE? If not then argument like Steve Jones' above don't apply.

April 21, 2011 | Unregistered CommenterGlenn Broadway

Why is Steve Jones (first post) going on about diesel cars being 11p per mile? Thats exactly what Robert says in the blog

April 21, 2011 | Unregistered CommenterWill Bick

I think to get under 40 miles out of Leaf would take some doing. Heater full on, massive hills, driving like a loon, maybe you'd get it that low but you'd really have to make an effort. In the Mitsubishi iMiev I drove last year, I certainly noticed a range decrease in very cold weather (we had -15 here) and running the heater certainly lowered it, but not catastrophically. You're looking at 10% range reduction, so if on a good day, on a flat road you can get 90, on a freezing cold day, with steep hills, lights, heater, radio on, 50-60 easy.
I've only had the Leaf 4 days so I truly don't know, I'm sure I'll find out

April 21, 2011 | Registered CommenterRobert Llewellyn

| Stephen Mackenzie

Good question, the heater is like a fan heater, with an element that heats the air. Electric motors are too efficient to pump out masses of waste heat, important to remember how much fuel you waste in an internal combustion engine, only 30% efficient at best. Electric motor is 80% efficient at worst. But heater or air con is a drain on battery and does effect range, most people say around about 10% reduction in range if you have it up high.

April 21, 2011 | Registered CommenterRobert Llewellyn

Steve Jones

Not quite sure what you're getting at. I state quite clearly, "55 mpg is 11p a mile" for diesel, which is exactly what you say.

However, consider this.
10,000 miles in a Leaf =£200
10,000 miles in diesel @ 55mpg = £1,100

April 21, 2011 | Registered CommenterRobert Llewellyn

I assume that even with overnight charging it would struggle with the 40 mile round trip to work and back

In other words 'I've just made some figures up, how about that?' Well yeah, what if I assume it can do 2000mpg? What about that assumption? Talking bollocks adds nothing to the debate. Your assumption that turning the heater on and going up some hills will more than halve the range is pure conjecture without any basis whatsoever in reality.

April 22, 2011 | Unregistered CommenterDavid Cameron

Hi there, thanks, the 10% figure does help and is less than what I expected - and which means that the leaf is a viable possibility up here, I'll give it some thought (although, as mentioned, I would prefer it if I knew that the range indicator was the least optimistic figure available, perhaps it already is, but would be good to know.)

David, I take your point but I think that what I was really asking was "what is the correct assumption for the reduction in range when the Leaf is taking on hills and with the heater full on since that is my major concern" which Robert has answered pretty well. Hope that my post didn't annoy you too much.

April 22, 2011 | Unregistered Commenterlaughinggorilla

I'd love an Electric as my next car. Quite apart from the charging situation (difficult when you live in town) it's not going to make financial sense for a LONG time.

I've had my current car for 5 years, and travelled 30000 miles in that time. I bought it used for £5k, and 30000 miles at around 40mpg/current price cost £4.5k.

The initial cost price of electric is the killer. They only make sense to people doing big miles, as that's the only scenario where you save enough on fuel to make up for that purchase price.

Personally, I'll probably try and buy an electric/diesel range extender when they become available. Seems like a better compromise - smaller batteries for close journeys on electric (small battery cuts costs too) with a diesel extender engine for efficient long distance use.

April 22, 2011 | Unregistered CommenterAndyB

Are they like laptop batteries.


Well, yes, it's principally the same technology. But assuming regular use like most cars - perhaps being left parked at an airport for two weeks at most, and only now and then - EV batteries will last, comparatively, much longer than laptop batteries.

This is due to them being in constant use, unlike a lot of laptops which tend to be used plugged into the mains with the battery fully charged 'just in case' - leaving a battery fully charged but not in use prematurely ages it and decreases its operational lifespan. Ideally it should be left at around 40%, and then charged when you know it'll be needed - or just used once or twice a week instead of being run off the mains.

I would expect EV batteries to still hold a useful range until the typical end of life of the car (100,000 - 150,000 miles).

OT but with the charge socket and flap there, I can't help but think someone would snap it off if you left it charging in public. Not because it's an EV, but because some people are t***s.

April 23, 2011 | Unregistered CommenterDan

...So about the same range (power) reduction as in a fossil-fueled car with air conditioning? Sounds about right.

I know electric motors are more efficient, but they must produce waste heat that can be reused. That would be the first and second laws of thermodynamics. Or something.

April 24, 2011 | Unregistered CommenterStephen Mackenzie

Joe Lynam BBC

To start with, I take back any 'agenda' suggestions I made, it does beg the question though, why is the BBC seemingly so critical of electric vehicles. (See Brian Milligan's ridiculous escapade in the Mini E) Yes, they're expensive now, but obviously they won't be in the future. Did the BBC run 100's of stories about how rubbish early mobile phones were? I can't remember, but they probably did.

But, oh dear Joe, I'm afraid you have proved everything I state in this blog.

The Chevy Volt is a range extended petrol/electric car

This is from the Chevrolet website.

A small, quiet on-board gas generator creates electricity that powers your Volt as you drive for hundreds of miles on battery and gas power.

I repeat your phrase 'range anxiety?'
Obviously the use of the term 'gas' refers to what we would know as petrol. You actually drove the car and you didn't know. Not only that, but the still image used at the top of the clip has a shot of the dash in the Chevy Volt, and there, clear as day is the term 'MPG' which, I will now inform you stands for 'miles per gallon.'

I drive a Nissan Leaf, it doesn't have a petrol engine, it is not a 'range extended EV' like the Volt, and all the points you make might have been valid if you'd been in one of them. I know you had shots of one, but you did your piece from an EREV.

We do need a rapid implementation of a charging infrastructure but we don't need journalists harping on about 'range anxiety' which as you will see from the comments, was a term devised by General Motors when they withdrew their EV1 car (featured in the film 'Who Killed The Electric Car') and introduced the civilian Hummer. It's a myth, it's nonsense, it doesn't happen any more than if you're in a petrol car and the needle is pointing to E.

So, all that said, I stand by my comment, shoddy, rapidly thrown together, ill researched, shoddy journalism. I don't blame you personally, I know you are under pressure from the BBC bosses to churn out 'the content.'
I just want to know why, who's steering this output, what is said at editorial meetings when this topic comes up. It's a mystery and I'd love you to explain.

May 8, 2011 | Registered CommenterRobert Llewellyn

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