How long does it take to fill up a car? When the difference between a fast fuel pump and a slow one and a big tank and a small one is three minutes, the answer is ‘who cares?’.

That said, I still find filling up with fuel quite tedious, largely because you have to stand there looking at your money ticking away for the whole duration.

Even so, the question is more pertinent with EVs, which is why, since 2022, our road tests of electric cars have included a rapid-charging test, where we measure how many kilowatts an EV can pull at increments of 10% state of charge.

In recent years, we’ve seen rapid increases in the speeds that both cars and chargers can reach. Our 2019 road test of the Audi E-tron complained that its 150kW peak charging speed was effectively pointless because such chargers hardly existed in the UK. Today, 150kW is about the lowest we would expect from a new EV or a newly installed rapid charger.

But the truth is that actually the answer is still ‘we’re not sure’. When we do these charging tests, we often use the charger at MIRA, which is well-maintained and tends not to be busy and therefore reliably puts out its maximum 300kW if the car can take it. If we use an external one, it will be at a site that we know from experience is reliable and at a time when it’s not very busy.

And there lies the problem: if you rock up at a site with eight 350kW chargers but there are a couple of Porsche Taycans hogging all the juice, the chance that you will get the advertised speed is slim, because it’s unlikely there are enough amps coming from the grid to feed 8x350kW. Chargers are good enough nowadays that you will probably be able to plug in and get a reasonable 100kW, which will suffice in most cases.

But it does call into question the sense of the sky-high speeds that some recently announced cars can allegedly reach. The Lotus Emeya will do 420kW, but I had to drive to Birmingham to find a suitable charger – one promising 400kW. (That’s not a slight on Birmingham, by the way; I just have little cause to go there otherwise). The facelifted Xpeng G6 will allegedly do 451kW.