If you are not interested in electric cars or public charging infrastructure then I will let you off reading the rest of this post now.
For those who are interested in the subject then I thought I would use this post to tell you about an experiment I have been running here in the UK since April 2015. To give you a little background I have been interested in EVs (Electric Vehicles) for some time now, starting with Hybrids and for the last 4 years driving battery electric cars only. BEVs have no backup, no engine to use when/if the battery is flat, so you rely on two types of charging, home charging (usually done overnight) and public or destination charging when your away from home. Here in the UK we are very fortunate we have a lot of charging infrastructure, most service stations on the motorway network have rapid chargers and a lot of major carparks have charging facilities as well.
I wanted to see if it was possible for an electric vehicle owner to only charge their car from publicly available charging posts. This was not about the cost savings (although I did monitor this) it was to really see if the infrastructure was up to the task and could someone who has not ability to charge at home (someone who lives in an apartment) own and operate an EV.
In April I purchased an adaptor for my car that would allow me to use CHAdeMO based electric vehicle chargers (the most prevalent DC fast charge standard in the UK) as well as Tesla superchargers and other type 2 charging stations that the car supports natively. The cost of the adaptor was £350. As I said this was not about saving money but I used this figure to see if I could use only public infrastructure until I had recouped the cost of the adaptor. The adaptor (pic below) allows the car to recharge at up to nearly 4x the rate it would using the 11Kw internal AC charger,but only a 1/3 of the rate of a Tesla Supercharger, so it was an mid level solution. This effectively allows you to spend 1/4 of the time you would normally charging at motorway services.
The car has a real world range when charged to 90% (the normal daily charge limit) of about 240 miles, given my normal routine only takes me 20-30 miles a day, charging only needs to happen about once a week, unless i was taking a longer journey such as our offices in London or to the airports which would take me near Tesla Supercharger anyway.
I set about recording how much power I drew from the public chargers and working out how much money it had "saved" then deducting this from the total cost of the charging adaptor.
So how did I calculate the savings, well if I were to charge at home it would only happen at night, on cheap rate electricity, however all the charging done during the trial was during the day so at full rate. In order to make it fair I took the average of the two rates and calculated savings at that price.
Also as most of my charging was opportunistic I tried to do it at times outside the normal rush hours, and always moved when someone needed the chargers, so my experiment would not hold anyone up. Below is my charging record for the period of the experiment.
So how did it go, well the short version is very very well, Since April I have not used anything but public charging, I over this period I drew 3207 kWh of power, and calculating my average miles per watt travelled, I was able to driver 9625 miles for free.
In 8 months I saw very few failures of the charging infrastructure, two broken handles on the charger heads and a single charger failure. During this time I used 4 different charging networks, those were Ecotricity, Tesla Superchargers, Source London and Source East. The charging stations were busier during the late summer months and as you can see thats when I drew most power (running around on late summer days and charging in the evening), and thats when I saw the wear and tear on the chargers. The old style heads are being replaced with new ones that are easier to use and a lot more robust so this problem should go away.
So I have saved myself £350 of electricity, so why do I state above that its not about cost saving, well two reasons firstly each charge session was about 25 minutes, so thats 25 minutes of my day I had to give up (normally I would charge the car while sleeping), but more importantly each time bought a coffee and a chocolate thing from the local vendor, so to save myself £2.50 of electricity at home I spent £5 on coffee and cakes. So the reality is unless your extremely dedicated, have a lot of spare time, an aversion to good coffee and chocolate things you are not going to save yourself money by trying to repeat this.
So to answer my own question, can a man live by public charging alone, yes he can however its a huge time suck, its bad for your waistline and you develop a caffeine addiction.
There is one positive to add to the list above, you get to meet some really nice people at the EV charge points, those who are there to charge their own cars, but huge crowds of interested onlookers asking "how far does it go", "how long does it take to charge", "is it a milkfloat" and asking if they can take a photo of you and your car.
To conclude, the experiment is done, I am going back to charging at night at home while I sleep and giving up my coffee and cake habit :-)
