How fast is a 7kW charger?

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man plugging charger in to ev

Just how fast is a 7kW EV charger?

In this article, we will look at how fast a 7kW EV charger is at charging your electric vehicle. These EV chargers are often referred to as fast chargers, so let’s dive in and see.

7kW EV chargers

EV chargers with 7kW power outputs are most commonly found in domestic homes, as they work with single-phase electricity. Some businesses may also have these installed in car parks. Very few homes have 22kW EV chargers, as these require three-phase electricity, which is very rare in UK homes. Most 7kW EV chargers will add around 25 miles of range to your car per hour. When you compare this to the alternative way of charging, via a 3 pin pug which adds around 4 miles per hour, this is a faster way of charging your EV.

Not all 7kW EV chargers are the same

When we say 7kW this could include chargers from 7kW up, any extra points after the 7 can make slight differences to how fast your EV charges. The range of EV chargers we sell charge at different rates, our Project EV charger is 7.3kW and our Easee One is 7.4kW.

How to work out charging times?

How do I work out how long it takes to charge my EV, we hear you ask. Well, in order to work this out, first you need to know the kW of your charger, then you need to know the kW of your EV’s battery. Once you have these two bits of information it’s a simple calculation.

Battery capacity (kW) divided by the charging speed (kW) of your EV charger.

So if we took for example a battery capacity of 42kW and a charging speed of 7.4kW.

42kW ÷ 7.4kW = 6 Hours and 10 minutes to charge your 42kW car battery.

You can also use this simple equation to determine how long it would take you to charge your vehicle at a supermarket charger or a rapid charging station when out and about. You could also use the equation to work out how much it costs per hour to charge your EV.

What affects EV charging time?

Is there anything that can affect how long your EV takes to charge? Yes, quite a few things that can affect it.

Temperature: As cold weather can sap power , this can slow down your charging speed and reduce your vehicle range.

Voltage drops: If your EV charger cant get the correct voltage then this will affect the speed at which is chargers your EV, this happens if your home is using more power than your electricity can supply.

Vehicle onboard charger: If your EV’s onboard charger has a maximum rating that is below 7kW this will affect charging speed. (Don’t worry we’ve explained what this is below).

What is an onboard charger?

All EV’s have an onboard charger, the purpose of it is to convert AC (alternating current) from the Grid to DC (direct current) for the battery. At public charging stations they mainly have rapid chargers which have built in DC converters, (usually a CCS connection) hence they are able to charge your EV quicker. Onboard chargers can have different power ratings, the most common found in full EV’s is 7kW, but PHEV’s will usually be just 3.3kW. Meaning even if you have a 7kW home EV charger your car can only charge at a rate of 3.3kW.

Is a 7kW EV charger fast enough?

Yes, unless you’re in a real hurry for a top up, a 7kW charger will be plenty fast enough to keep your EV charged and you on the move. If you’re in a rush on an odd day you could use a rapid charger which charges your vehicle in no time at all.

If you don’t already have a 7kW EV charger installed at home what are you waiting for? Get in touch with our sales team now and get one installed within days.