The electric car experience: how charging numbers stack up
I said in the last post that getting the electric Volkswagen ID7 made me unlearn long-held assumptions about filling up and that the Electric Vehicle experience is like having a fuel tank fairy… I want to dig a bit deeper, because when going electric is suggested to non-EV drivers, range, and time to fill are cited as worries.
Filling with petrol or diesel is so familiar that we take the mechanics of the process for granted. To spell them out… When I returned home with the old car, its tank might be nearly full or nearly empty. When I set off the next day the amount of fuel in the tank gave me some range, and each round trip to somewhere and back reduced the range for the following day, until I needed to fill up; doing that took 5 minutes or so, with a perhaps a 5 minute each way detour to Tesco: up to 15 minutes in all, a couple of times a month. There was little sense in filling up when half full, or in only filling halfway.
Now, I leave the ID7 out for the same “recharge fairy” who sorts out my headphones / laptop / phone; it doesn’t matter if takes all the time I’m asleep or just half of it to charge, in the morning there’s enough battery for the day ahead -almost every day…
The car, and Windows on my laptop, tell me to reduce battery wear by only charging to 80% unless I expect to need more. Rapid chargers used for en-route charging use DC up to a 500 Amp limit set by the connector; so with its 400Volt battery, the ID.7 can’t exceed 200kW however fast the charger. Like a laptop or phone, charging slows down as the battery fills up. VW set an expectation of 20-80% in 25 minutes, which is an average of 110kW, starting around 180 and gradually dropping. It’s an expensive way to charge - sometimes over 80p per kWh, compared with 7p per kWh overnight at home on much slower AC, and cost considerations mean thinking about “back to the charger” round trips, not one-way journeys. They break down like this:
- Local journeys, round trips under 50 miles in total, commuting, shopping, school runs, errands etc. By far the most journeys, but not always the most miles.
- Longer occasional trips with the round trip less than range.
- Longer occasional trips with the round trip slightly more than the range.
- Rare, ultra-long journeys where each-way distance exceeds range and round-trip is well beyond 2x range.
1 and 2 don’t need charging stops. 3 needs a short stop to add enough charge to finish the journey. 4 needs a closer look but we shouldn’t obsess over it.
I remember this Audi advert from the late
1980s:
Every year the Schmidts, Mullers and the Reinhardts drive to their holiday
villas
The Schmidts’ car is slow and rather noisy…[They’ll need another holiday to
recover]
The Mullers drive a big thirsty car which is probably at a petrol station
somwhere between Munich and Marbella
Woah! Munich to Marbella one-way is 1400 miles and 24 hours of driving! When
I was a teenager, my dad drove the family from Brighton to Bordeaux, which is
half as far, and we needed an overnight stop.
The Reinhardts drive an Audi 100…
Bookending holidays with that sort of drive and racing other nations to the beach may have gone the way of leaded petrol, but “Those poor Mullers needed to stop” thinking hasn’t. With a light right foot, the Audi driver only needed to fill its big tank once. But everyone needs stops on that length of journey, especially if one person did all the driving, like my dad did.
I once drove 700 miles each way to an event in Berlin to make a point about company travel. The last time I drove as far as Glasgow was four cars ago, so this car might never do a round trip beyond 2x battery range. People do 3000-Mile road-trips across America, but Moscow or Istanbul are less than 2000 miles from here, 3000 takes me to Iraq. Exceptional journeys should be treated as such.
My family has links to Tenby and I do drive there which is 200 miles each way. I need a break after a couple of hours. The battery only needs enough for the next stint, and a low battery will charge sufficiently in the time it takes to get a coffee. Part of the decision to get an EV was realising I could do that trip, just plugging in at the stops that I’d always made. But standing at a pump in horizonal, freezing, rain, just because the time has come… that’s a thing of the past. With an EV you fill at home before the battery is empty and don’t fill completely when away from home - both changes from the tank-filling behaviour I described above.
The worst case is when I can drive one-way in a single stint, won’t charge before returning, and the battery lacks the range for two full stints. 100 miles each way isn’t limitted by me or the battery, 200 is limited by both, but around 150 the battery will cry “enough” just before I will. Let’s compare the ID7 and the diesel CC it replaced:
~300-mile battery | ~600-mile Tank | |
100 miles out / 100 back | Non-Stop. | Refuel only if starting |
150 miles out / 150 back | Charge stop required, | Refuel only if starting |
200 miles out / 200 back | Comfort stop required, | Comfort stop required, |
400 miles one way | Comfort stops required, | Comfort stops required, |
600 miles one way | Comfort stops required, | Comfort stops required, |
Because it sets off with a charged battery, the ID7 never needs to fill up on
trips under 200 miles. With its 600-mile tank the chance the CC needed filling
up was JourneyLength / 600; on one 200-miler in three it would lose out to the
electric car, but the other two it would manage a draw.
For the 300-mile round trip the ID7 needs a short charge every time, the CC needed filling only half the time (a draw) and would win the other half the time.
Past 400, driver / passenger endurance sets the limit; when everyone has had their break the ID7 is ready to finish the journey but there’s 2/3 of a chance the CC would lose because it needs to double-stop to fill up.
So, unless those 300-mile trips are the majority, the old car loses because it must go somewhere to fill up once every tank-range. Topping up at home allows an EV to cover many times its battery range between journeys that need a charge, and for most of those, it’s using existing stops not adding any. Time to give yourself 300 miles of range doesn’t matter because it’s fewer miles until the next stop, and you don’t want to return home with a lot of expensive charge unused.
But what about finding a charger?
The UK had 8,353 Petrol stations at the end of 2023 with an estimated 8 pumps per station, that’s about 1 pump per 500 combustion-engine cars –their use is predictable: we know how often they need to fill and how long that takes, so we can calculate pump utilization. Experience shows queues are rare with the utilization we have.
What level of utilization is ideal? What proportion of EV trips will need a charge? How long will a car occupy a charger? What drivers do while their cars charge may matter more than the amount or speed of charge. Any “chargers needed” figure is guesswork; and drivers without a home charger are a separate question. But it’s a fair guess we won’t want to be much further from a charger than from a pump when we need one, so eventually we’ll need a similar number of locations.
In February 2025 Zapmap’s database of UK
points showed, counting all speeds of
charger, the UK has more chargers than petrol pumps. But concentrating on rapid ones, there
are 5850 locations in the UK of which about 5000 are in England which conveniently has an area of
50,000 square miles - making one for every 10 square miles. In some rural areas – and
most of Scotland and Wales are classified as rural – the nearest charger is
a long way away, but so is the nearest petrol station or shop.
The sat-nav in my old Volkswagen had an out of date list of petrol stations (no Point-of-Interest updates)
but it couldn’t factor them into a route based on fuel in the tank and expected
consumption. The ID7 will say “Oh, you want to go there with this juice… OK,
we’ll need to stop here - from a live list - and add this much, I’ll pre-warm the battery so you get the
best charging speed and you get a 12 minute break” – it’s not a purely EV thing
but navigation has improved a lot since VW last updated the CC. Finding the nearest suitable place to fill is
easier, and whilst I wanted loyalty points when I bought diesel so would look for a Tesco, I don’t care about charger brands, so location is the main factor
The ID7’s guidance updates to reflect battery use, so when mileage was better than expected the car told me I no longer needed to stop to get home. The car isn’t the only source of infomation about charge points, there are multiple apps, and I’ll talk about the data around charge points and what we can learn from it in another post.