When you are at a filling station with an old-fashioned car with an engine, you are given a choice of a few different pumps. There’s petrol and diesel, usually in a couple of different grades, and you simply choose the right one for your car.
With an electric car you are never at risk of putting the wrong type of electricity in your battery, but there are different ways of charging your car to suit every situation and your particular vehicle. In a hurry? Choose a rapid. Parked up for the night? Look out for a more leisurely AC charger.
Shell Recharge offers a wide variety of places to plug in, at locations ranging from service stations and supermarkets to streets. Here are the differences between them, and how to choose the one that is right for you and your car.
Shell Recharge points can be found at all sorts of handy places, including supermarkets
Rapid and Ultra Rapid DC chargers – for when you are in a hurry
As the name implies, these chunky-looking chargers offer the fastest way to get power into your battery. As they supply electricity in the same Direct Current (DC) as the car’s electrical system, it can bypass the bottleneck of the vehicle’s on-board converter so you’ll see your battery level rising far faster.
There are different power DC chargers available, with Shell Recharge units varying from 50kW to a massive 360kW. Your car might not be able to accept the higher rates though, so it is worth checking the specifications on Electrifying.com’s reviews before you pay extra for a faster charge.
The most powerful Ultra Rapids are ideal if you need to add some miles to your range, such as if you are on a longer journey or are a professional driver who needs to get a top up during the day. These can add around 100 miles in less than 20 minutes in a suitable car.
You may also want to choose a less powerful 50kW charger if you don’t intend to wait around and will be away from the car for longer. That’s why Shell is using this for the points it is installing at up to 100 Waitrose stores across the UK.
These lower power Rapid chargers are also cheaper to use, so are perfect if you have a car which is not capable of accepting a higher feed such as a Nissan Leaf or Ora Funky Cat.
Ultra Rapids can feed up to 360Kw into a suitable car, adding 100 miles in less than 20 minutes
AC chargers – for when you are parked up and doing other things
Our cars spend most of their time parked up doing nothing while we sleep, work, shop or gossip with friends over a coffee. This is the perfect time for you to plug in and charge.
Most modern electric cars will accept 7.2kW from a wallbox or on-street charger such as those offered by ubitricity, which means they are ideal for ‘filling up’ overnight or while you’re working during the day. Simply plug them in and then get on with your life, confident that the battery will be replenished when you return to the car.
A slower charge will also allow you to take the battery to 100% easily if you need to go on a long journey. You can do this on a DC charger too, but the last 20% of the charge will not be any quicker than using an AC point, so it makes sense to free up the Rapid for someone else to use. It will usually be cheaper too.
If you prefer a ‘halfway house’, some cars will take up to 22kW from a suitable AC charger as they have the on-board hardware which can take the bigger feed. This is why Shell has invested in providing these faster AC points at supermarkets such as Waitrose. These will allow you do add a decent amount of range while you are shopping, for example. A 45-minute connection could add around 70 miles to a family car1.
An AC charger is ideal if you are parked up for a longer period or overnight
How quickly will my car charge?
If you remember science classes, you will know that a 50kW charger will be able to get 50kWh into a battery in an hour. But in reality, you will get less than this for various reasons, so leave a little longer if you need the power.
Because batteries have very delicate chemistry and can be easily damaged by an electrical overload, all electric cars limit the speed at which power can be fed into the batteries, and charge speeds fluctuate.
When using a Rapid charger, your car instructs it to start slowly before it runs at full speed. Even at full flow, your car may well trim a few kW off the amount the charger can actually deliver to ensure that the battery isn’t getting too hot. If the weather is chilly, the battery cells won’t be as active either so might not take a charge as quickly, or may use some of the power to warm the cells.
This will usually mean that your car will charge at different speeds in more extreme weather conditions, and also depending on if you have been driving before charging.
A charger will also be able to get energy into the cells faster if the battery is emptier. Then usually at around 70-80%, the power delivery is turned down again to eliminate the risk of damaging the battery.
It sounds complicated, but even in the worst case you will only need to stay for a few extra minutes, and some of the time you’ll find your car has charged faster than you expected!
122kW for 45 mins = 16.5kWh. A family car such as a VW ID.3 58kWh has an official consumption figure of 4.55 miles/kWh, therefore a 16.5kWh charge would enable it to cover 75 miles.