Hanna, Ian’s niece,
demonstrates how to charge Ian’s electric BMW.
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What sort of car do you have?
IanI have a BMW I3 REX. The REX stands for range extender. This means as well as the battery it has a small (9 litre) petrol tank that can run a generator to charge the battery if it gets low. It still ‘counts’ as a zero emissions vehicle, though, so I could drive it in California if I ever wanted to. In fact I have hardly used any petrol – I have only bought 4 litres of petrol in 5 months.
James
Ours is a Nissan Leaf. It’s pure electric.
How far does it go without charging?
IanThe specs say 70 miles plus another 70 from the range extender but in fact it depends on your setting because that controls how much heating and A/C you get. Heat is cheap in a conventional car because the engine generates a lot of waste heat but in an electric car heat is extra. So there are three settings:
- Eco pro plus - no heating or A/C
- Eco pro – with heating and A/C
- Comfort – with heating and A/C and a heated seat.
I mostly use the first setting, Eco pro plus with no heating. I have been known to wear hat and gloves in the car. Sometimes I put it on the next level though, which is the middle one and that is the 70 miles range. So I get more than that usually.
In practice we mainly use the car as a town runabout and to visit an aged mother in Bury St. Edmunds. That’s a 65-mile round trip, well within the normal range.
You can get cars with much bigger batteries now. Mine has 20 kWh but you can get a car with 70 kWh that does 250 miles. A typical battery provides 3.5 miles/KWh.
James
In theory ours is supposed to go 150 miles but in practice we get about 120 miles range from a 30 kWh battery. The range you get depends on your driving style: there is a display on the dashboard that tells you your current predicted range, based on the state of the battery and how you are driving. If you accelerate hard then the range goes down.
Also the range varies with the weather. It does less well in winter – I think that could be because the battery is cold. I don’t think heating has much to do with it. If you turn on A/C then the range goes down but only a little.
The Nissan Leaf has an Eco mode that you can select. This reduces the throttle response. We use that most of the time but turn it off when we really need acceleration, like on a slip road going onto a motorway. Also there is a B mode that increases the regenerative braking.
You get more range if you drive slower. I usually drive at around 60 mph rather than 70mph on the motorway, and that makes quite a difference.
How do you charge it at home?
IanAt home I have a level 2 charger which is one step up from a normal plug socket. On a normal socket you would use a level 1 charger and that could take 8 hours. I got an electrician to install a special circuit to the garage for my level 2 charger and that takes at most 3 hours. In service stations they usually have a level 3 charger and that only takes 20 minutes.
I try to charge from my PV panels whenever I can, when the sun is shining. We have an export meter and I have noticed the amount of electricity we export is significantly less now we are using it for the car. We currently export less than 25% of the 3400Kwh generated from the array.
James
We don’t have anywhere to charge at home because we have no off-street parking and there aren’t any charging points in the street. However, my wife Hannah works in Papworth and her work has solar panels and a charging point there. She works 3 days a week but she makes sure we have a full charge for the weekend.
For the Nissan there are three charging speeds depending on the charger being used; slow, fast and rapid. Hannah’s work charger is fast, which means in our case with a 30 kWh battery it can charge up in 4-6 hours. So we can get a full charge in during the working day.
However, the charging rate is not linear. It charges quite quickly to start with and then it slows down for the final topping up. When we are at a motorway service station with a rapid charge point we can get up towards 80% charge in about 20 minutes but it takes up to 45 minutes for a really full charge.
There are quite a few charging points in and around Cambridge. Since we have a Nissan we can charge for free at the Nissan dealership on Newmarket Road but that is only during office hours. There is 24 hour Ecotricity one at the Cambridge Services on the A14. You can also charge at Park and Rides though I believe you have to have a Source East card for that. It is only £10/year and then charging is free at lots of points in East Anglia but we haven’t needed it.
I've heard it said that a full charge costs about £2 worth of electricity but I’ve never checked this.
I think the placing and nature of availability of charging points is more critical for older cars with shorter range.
Where do you charge it when you are away from home?
IanWhenever I go anywhere away from home I always ask about charging points but I have learnt that when they say yes it often just means a plug socket - which is no good if you’re only there for a couple of hours. I know now where I can get a nice meal and charge my car at the same time!
Service stations usually have a type 3 charger, as I said and they are often free to use as they’re subsidised by Ecotricity. But there are other places you can charge as well. I use an app called zap-map that tells you where there are charge points you can use. There are quite a lot in Cambridge.
When we stay in our cottage in Norfolk I take the car to a local farm to charge. The power socket there is powered from an Anaerobic Digester – so that is renewable and low carbon.
James
I mainly use service stations when I have to travel. For example I had to go to a meeting in Oxford one day (83 miles) and it turned out there was a rapid charging station on the North side quite close to where I had to be. So I went there first, had a cup of coffee while the car charged up, and then went to my meeting. Afterwards I could come straight home.
When we go to Worcestershire, which we do quite often to visit family, we can almost get home with just one stop but since we can’t charge at home we have to stop again at Cambridge services. Otherwise Hannah might not get to work in the morning.
Our rental deal includes emergency recovery if we run out of charge but it hasn’t happened yet.
You have to be prepared to adapt your route. When we went on holiday in Wales we went through South Wales so as to stick to motorway as far as possible, to make sure we had places to charge on the way. We also overnighted in Bristol to break the journey as with charging stops making the whole journey time quite long it was nicer to break the journey into two.
It is worth remembering that there are different connecting systems for different kinds of cars. For example Nissan, Renault and Tesla all have different systems. If you use zap-map you can set filters for what sort of car you have and what payments systems you are signed up for. The rapid chargers on the motorways, which are free, have two types of connectors so they can charge Nissans and Renaults. Tesla have their own chargers at some motorway services but they also have a much longer range.
How do the carbon emissions compare to a conventional car
IanThe car is rated at 13 g/km but that figure seems to be based on zero emissions except when using the range extender.
Since I run it on renewable electricity most of the time, the carbon emissions are very low anyway.
However, if you were to use normal UK grid electricity, at the rate I am getting (5.6 km/kWh) it would be about 80 g/km. This is quite a lot less than a comparable diesel car - about 99g/km.
As for embodied energy, I haven‘t been able to find out. The BMW dealer just looked blank and changed the subject when I asked. Eventually I found someone who told me that their assembly plant in Leipzig runs on renewable energy. That’s good but it says nothing about where the parts are made.
James
To be honest I have no idea. If you charge at an Ecotricity station, does that count as zero carbon?
I don’t know how much electricity the car has used. Usually charging is free so I don’t take note.
Judging by the 120-mile range, it must be no more than 4 miles/kWh so about the same as Ian said.
But the electric car is low in other emissions too. It produces no exhaust emissions such as NOx which are a big issue now in urban areas. I assume there are still some particulate (PM 2.5) emissions from the brakes and tyres, so it isn’t perfect – no car is.
How much does it cost to buy and to run?
IanWell fuel-wise it’s very cheap, especially using our own PV electricity. Scaling up from the 5 months so far (3400 miles) I reckon I will save £500/year on fuel plus another £500/year in reduced road tax, congestion charge (it is zero rated) and less servicing costs. Electric cars don’t need so much servicing because the electric motor is much simpler than an engine.
The car cost me about £5000 more to buy than I would have paid for a conventional car. (This is second hand but less than a year old). So it should pay that back in 5 years, if I keep it that long.
James
Fuel is mostly free, at least at the moment because Ecotricity and other companies subsidise the fuel to encourage take-up. But even if you have to pay I think it is only about £2 for a full charge. (If that takes you 100 miles, it compares to about £11 for a diesel car that gives you 48 mpg).
We have a 2-year rental agreement and it costs £4056/year including the annual service and breakdown recovery. We still have to pay insurance though, and since that is based on the value of the car it is quite expensive. Also, if we go over the mileage we estimated we have to pay Nissan another 8p/mile.
You can get a lower-spec car much more cheaply. For example a friend of ours got a second hand Nissan Leaf with a 24 kWh battery for only £7000! But if you buy second hand you have to think about battery life.
We specifically wanted the extra range from the 30 kWh model and we hope there will be another model with a longer range available when this agreement runs out.
What is it like to drive an electric car?
IanThe car is very light in weight and I think that is why it is incredibly quick to move off from stationary. You can be first off at the lights, if you want.
Another thing is, it’s very quiet. Pedestrians don’t seem to notice it coming sometimes, so you have to look out.
Braking is different. There is a brake pedal but usually you just ease off the accelerator. This triggers regenerative braking. It takes a bit of getting used to and it may be hard to switch back, as well.
Anyway I like this one so I don’t think I will need to switch back.
James
I haven’t noticed doing anything different with my pedals compared to other automatic cars although I haven’t had much experience of driving an automatic car prior to this one.
Anyway I love driving this car. It’s a bit surreal because it’s so quiet, especially at low speeds. Also it handles better than the diesel Polo we had before.
Do you have any other advice for people thinking of getting an electric car?
IanI would encourage individuals to explore the option - with a growing a public network of charge points, a user community that is offering shared charging (plug share) and vehicle range increasing - the anxiety that often comes with new technology is rapidly disappearing.
It's not an impulse purchase. Understanding your driving requirements is very important and although more expensive than an equivalent traditional petrol/diesel engine vehicle, the payback time is short (less than 5yrs) and C02 reductions are from day 1.
James
Just a couple of points, maybe. Firstly, you can set a timer on the charging so as to take advantage of cheap off-peak electricity if you have access to that. Also, I think Ecotricity offer a discount to customers that have electric cars. (Yes they do: see here). Only I’m not sure it would apply to us as we don’t charge at home.
I would encourage everyone considering getting a new car to consider a pure electric one and to see if it could fit with their needs and budget. It would also be worth considering if any new models expected in the near future might be a good option too. Once our current rental finishes I am hopeful we might be able to look at next generation Nissan Leaf, an affordable family Tesla and whatever else has come out by then. Not only does having an electric car help lower our carbon footprint, contribution to local air pollution, and fuel and road tax costs, it also protects us from potential spikes in petrol costs, if carbon pollution starts being regulated or priced into the market more strongly as a response to increasing climate change.
There are a range of benefits from electric cars - reduced carbon emissions and NOx, less noise and smells, potential for using the storage to support the grid. How you value these is an interesting question. See http://energy-surprises.blogspot.com/2016/06/counting-benefits-of-electric-cars.html
ReplyDeleteAn update from Ecotricity is set out in the link below.
ReplyDeleteEcotricity customers will continue to receive 'free' electricity from the highway network of grid chargers run by Ecotricity along with a one off payment to offset their home electricity bill.
http://us1.campaign-archive2.com/?u=2e205e9bbdbea814f7a00ba2b&id=d33c9afd3f&e=452cccaa4
I think Ian should have started to say that Ecotricity have announced they will no longer offer charging for free to all. You will have to pay £6 to use their charging points for up to 30 minutes. Some people claim this makes charging too expensive, especially for vehicles with smaller batteries. They say the cost should be per kWh.
Deletehttp://www.cleanenergynews.co.uk/news/transport/ecotricity-to-allow-30-minute-charging-after-consumer-backlash
But as Ian says you can still get free charging if you are an Ecotricity customer.