Motorists who own an electric vehicle (EV) might consider using what is commonly known as a ‘granny charger’ to charge when an electric vehicle chargepoint (EVCP) isn’t available.

A granny charger is a charging cable that can charge an EV using a UK domestic socket. It is intended for occasional or emergency use, not as a main charging solution.

There are four common charging methods, called ‘modes’. Regarding granny chargers, those are known as Mode 1 & Mode 2 charging:

• Mode 1 AC single-phase or three-phase charging with a charging cable that does not incorporate any controls. The supply to the vehicle can be direct from a socket-outlet to BS 1363 (if EV rated) or BS EN 60309 socket.
• Mode 2 AC single-phase or three-phase charging, but with a charging cable that incorporates controls/protection. The supply to the vehicle can be direct from a socket-outlet to BS 1363 (if EV rated) or BS EN 60309 socket.

For World EV Day, celebrated on September 9th, the Electrical Safety Roundtable has put together some essential tips for motorists using a granny charger safely.

1.Use a dedicated socket – plug directly into a wall socket, never an extension or adaptor.

2. Check the condition of the socket – it should be undamaged and not discoloured.

3. Don’t use a socket already under load – avoid running other heavy appliances on the same circuit, the circuit should only be supplying the EV charger.

4. Check the wiring installation – older wiring may not handle long charging loads.

5. Protect the lead – keep cables dry, avoid coiling the cable tightly while in use, as this can cause overheating.

6. Use an RCD protected circuit – ensure the socket is protected by an RCD.

7. Avoid running long charges regularly – granny chargers are intended for occasional or emergency use, not as a main charging solution.

8. Keep an eye on it – don’t leave charging unattended for long periods.

It is key that granny chargers are only used occasionally or in an emergency. If you are considering getting an EVCP installed, see the ESR's essential tips for consumers to ensure a smooth and safe EVCP installation at home.

Householders must find a registered and competent installer who is qualified to install the chargepoint, do thorough research and know the right questions to ask to have confidence in their EVCP installation.

The ESR guidance covers some of the things that consumers need to consider. Read 10 ways to ensure a smooth and safe electric vehicle chargepoint installation at home.