How do Charge Points Work & How to Calculate Charging Times

Mode 1 & 2  slow charge can be achieved over about 7 or 8 hours and works by attaching your car battery to a general electricity supply. Slow chargers typically operate at 3 kW (13-16 Amps) and you can use a normal plug socket but it is advised to have a dedicated unit installed at home or work. The first initial public charge points were of this type but they are now being replaced by faster units.

Mode 3 Fast chargers deliver between 7 and 22 kW and provide a much quicker load time of three to four hours. As of September this year there were over five and a half thousand fast chargers in the UK.

Mode 4 Rapid chargers can come in either AC or DC. AC chargers up to about 43 kW can provide an 80% charge in about 30 minutes. A DC charger provides up to 50 kW and delivers a similar result. Whether your EV can take either the higher AC or DC charging will depend on your model of car and the kind of attachment you have.

Ultra-rapid charger delivers either 100kW, 150kW or 350kW. The most common rapid charger in the UK is the 50kW device.

Connectors also vary depending on the amount of charge you can have and whether it is AC or DC. You may need to buy different cables including a portable charging cable that allows you to safely perform a charge at home.

Remember this Principle

(charging calculation)

Example: Lets assume you arrive home at the end of the day in your kia e-Niro and are at 50% charge, and your battery size is (64kWh). You have a 7.4KW Home charger and you want to go from 50% (32 kWh) to 100% (64kWh), thats 32 kWh shortfall to make up.

All you need to calculate is the time its takes your "specific charger" to charge your "specific battery size", and the following calculation is:

• 32 kWh ÷ 7.4kWh = 4.32 hours ( It takes 4.3 hours to charge your 50% battery to full charge). From 0% to 100% it would take 64kWh ÷ 7.4kWh = 8.64 hours.