Brrr, sub zero Nissan Leaf range anxiety
Wednesday, February 8, 2012 at 3:44PM Just driven to the shops. Okay, that has to be the most banal blog post ever. The car is a Nissan Leaf, the weather is very cold, the route I take (I live in the Cotswolds) is very hilly. The shop is 7.4 miles away, so return trip is just under 15 miles. When I got in the car, the range indicator said 83 miles, The battery was full, ion a warm sunny day it would estimate over 100 miles.
(While I remember, as the car charged overnight on off peak tarrif, that 15 mile trip cost just over 15p)
When I got home it said 69 miles. I was doing rather immature tweeting that I was suffering gut wrenching range anxiety, the point is, in very cold weather, the cars range is reduced. Today we are hovering at around -5c.
I used the heater, the lights and the radio on the trip all of which have an impact on the overall range. This can be offset by pre-heating the car when it's still plugged in, which I also did.
I have discussed this issue with a couple of academics, both involved in fuel efficient internal combustion engine development, both petrol (gas) and diesel. I asked about a short (under 30 mile) trip in sub zero weather and how that impacted fuel efficiency in modern cars. One said 'catastrophically,' the other said 'dramatically.' Of course we don't notice that because the overall range of the car is greater, the re-fuelling is rapid and we're 'used to it. However the myth of the 60+mpg diesel is just that. On a short trip in cold weather, halve it for the first 20 miles until it's fully warmed up. Very inefficient, producing large amounts of SOX and NOX, the particulate filters (which cost a bomb and sap power from the engine) don't work until they're warm, but we're used to it.
We're not used to electric cars which can be pre-heated while plugged in, have a range reduction of around 15% in very cold weather and take a long time to charge, unless you use a fast charger, of which 600 are being installed this year.
The thing is, I'm getting used to driving an electric car and to be honest, it's quite good.
Reader Comments (12)
The more I hear about the Leaf the more i want one. Even with the limitations the new technology has. It seems to be to almost be a no brainer! Only thing holding me back at the moment is the initial purchase price and subsequent finance! Anyone wanna by me a leaf? ;-)
I had my name on the waiting list for the Leaf in Boston, MA and cold weather range was my biggest concern. I don't think they've launched the car in this area yet and I needed a car, so I bought a traditional ICE car but I'm still interested in electric and particularly the effect in New England winters.
There was a huge storm here a couple of years ago where journeys that normally took less than an hour were taking people 4+ hours. Lots of people ran out of fuel in their conventional cars and the filling stations had huge queues. I know that an electric car would not use any battery capacity in the motors unless it was moving (unlike an idling engine) but I wonder what the draw of the heater system is to keep the car at a comfortable temperature. An ICE has 'waste' heat, but it does mean you have to leave the engine running to get it. Maybe electric heat is more efficient. It's hard to know because the manufacturers don't seem to want to give out that kind of information.
Hopefully the data will be released, maybe by independent testing like this. Like it or not, range anxiety is the biggest hurdle to all-electric vehicles and the only way to overcome that is with data / proof.
Good post. I was expecing the loss to be more to be honest, and I never even thought of heating while plugged in. Great stuff.
Just wish I could afford one, or at least lease one from Nissan.
I drive a big old diesel, in this weather it takes about 5 miles to warm up. Never mind the fuel consumption and emissions during this time, I'm blummin' frozen until the heater pumps out hot air. Preheating? You don't know you're born!
Also - range anxiety. I had 70 miles remaining in my tank when I parked at work this morning. This will drop to 0 miles between now and when it warms up, before settling at about 40. The computer obviously bases it's range on the current fuel usage, and subtracts a few litres for safety. In those 5 miles, it must use a typical 30 miles of warm use diesel. :(
If I had the money, and a driveway or garage, I'd have a Leaf.
Grr. Wish my car would pre-heat in this weather.
I really, really want an electric car. I can also point out that my stinky diesel car has done 39 MPG instead if the usual 46. So not so great in the cold.
Very cold? -5c is very warm. It can hit -40c here or less near the end of January. I wonder what kind of rang I'd get, and how it'd do after sitting in a blasting -40 wind all day at the parking lot.
Being a little bit of a gearhead myself, it's worth pointing out that you can preheat conventional ICE-powered cars using block heaters, and use that to help reclaim some lost efficiency due to cold temperatures. They used to be far more common when cars started unreliably in the cold, but now that manufacturers have resolved that issue, you need to go out of your way to find them.
Now that I've said my piece on that, I'd love to own an electric car. The amount of driving I do fits in the range of both the Leaf and the MiEV/i (even the Volt in EV-only mode), I have no problem plugging things in on a regular basis (I'd already be doing this for my car on a nightly basis, if I could just find a block heater for it), and if I only had a garage to park it in (so I wouldn't need to run 50-100ft of power cabling to our driveway, and chances are since I'm just starting out in my career, I'll be living in apartments/townhomes/condos/etc for years to come) I'd be an ideal candidate for an electric car. The fact that there's only a 15% drop in cold-weather efficiency in an EV is great news, and if we could just back this up with a more comprehensive, scientific survey, perhaps we could finally convince manufacturers to start selling the things in my part of the US! As it stands, the only EV I know of that I can even test drive is the Chevy Volt, and that thing is way outside of any price range I'll be able to afford for some time (and much bigger than I need right now).
My car does about 300 miles on about 43 liters (crap I know) on the short trips I normally do.
If I do a long trips it will easy do 400 miles on the same amount of fuel so Rob is spot on
As battery performance decreases in the cold I assume you would not gain any advantage by using some of the energy in the batteries to actually raise the overall temperature of the batteries?
Robert, could you do an informal test to simulate being stuck in a traffic jam at the temperature of -5C? I was thinking of the EV being stationary on your drive in an exposed position with the heater on, for say 15 minutes to get an idea of the range reduction. Multiple that by 4 for an hour.
Personally, I carry a survival kit in my car during winter and would do the same if I had an EV, so I wouldn't need the heater on for long anyway, but it might be a useful exercise. Thanks.
Nice post.
I always wondered how much the on-board electronics drain the battery compared to the motor? If that is a singnificant amount, why do some electric cars (Teslas) use those huge ipad-like diplays which are always on and must suck up a lot of juice. On my mobile phone I can turn off unessential services and turn down the brightness of the screen to extend battery life. Does the Leaf have any such battery life tweaks?
I'm no expert, but going off a basic knowledge of how much power different electrical items consume, I wouldn't be worried at all about any of the dashboard electronics; LCD screens, stereos, phone chargers etc. I really don't imagine that they make any discernible difference to the range when you think a) how much current these batteries store and b) the relative consumption of the motor.
I assume the lights are super-efficient (LEDs?) but even still, I'd expect them to make a small difference. The heater is a different story altogether; the sort of electric heater you'd use indoors can take several kilowatts. So your best bet to extend the range in cold conditions is to buy lots of thick jumpers and keep the heater off!