Thoughts from an active pensioner who is now somewhat past his Biblical "Use-by date"

"Why just be difficult, when with a little more effort you can be bloody impossible?"



Wednesday 26 July 2017

Electric Cars

I had hoped to write something at least once a week, but unfortunately circumstances conspired against me, as, I suppose, one must expect at my age. Hopefully, I will now be able to write more regularly.

Today, I read slightly different versions of the story about electric cars; some reports insist petrol/diesel powered cars will be banned from 2040, others suggest that their manufacture will be banned. But whichever is correct, I wonder if anyone has considered the knock-on consequences.

Having been for my daily stroll, I noticed that there was a Mercedes in the drive of one of the houses connected to a specially provided outside socket and presumably being charged. Out of curiosity, when I got home I looked up the details.

According to the Mercedes web site, the B-Class has a range of up to 124 miles and can be charged in as little as three hours. Fortunately, Autocar provides more detail:
Fully recharging the B-Class via a 16-amp home wall socket will take around nine hours if the battery is empty. Using a 400-volt three-phase electricity supply (rather more common in Asia than Europe), the car can be recharged in just three hours.
Few homes in the UK have a three phase supply and those that do will have needed to have had it specially installed, so a full charge from flat for most of us would take nine hours.

Assuming that the full 16-amps is required, we can work out that on a 250-volt supply, the load will be 4 Kilowatts. Thus two hundred and fifty cars being charged simultaneously will present a load of a megawatt to the grid.

Going back to Google, I found that there are 36 million vehicles registered for use on the roads in the UK. Were the owners all wanting to charge them simultaneously (which I accept is unlikely), this would be a total load of around 144 gigawatts!

Looking elsewhere, I found that the maximum load that can normally be supplied from the National Grid is around 45 gigawatts, with an absolute maximum (when all plant is fully operational) of 55 gigawatts. Of course, as most of these cars will be being charged by night, solar power won't be available and wind power, as always, is in the lap of the gods. At the time of writing, the load on the grid is 35 gigawatts, so at the moment there is only about 10 gigawatts available for battery charging!

So, when does the necessary power station construction start?

Then there are all the further questions. What use is a car for many of us that only has, at best, a range of 124 miles? How would we manage to go on holiday, especially if we wanted to go abroad? I expect we will have lighter and hence larger capacity batteries by 2040, but they will either present a greater load to the grid or require even longer charging times.

And, of course, the usual question, compensation. Will all the redundant filling station owners, and possibly the petroleum giants, have to be compensated?

It is unlikely that I will be around to see what happens, and if I am it is even more unlikely that I would still be driving at over a hundred! However I expect the effects to start to be felt long before then as people start to buy electric cars in anticipation of the deadline.

In the meanwhile, I'm contemplating a Toyota hybrid. I live in a hilly area and I either have to go up or down hill as I leave home and I resent the waste of energy with the constant braking when I'm coming or going, so a hybrid seems a sensible option.