We have discussed the different rates of charge in the previous article so when selecting an EVSE you have the power level as a primary consideration but there are a number of other possibilities to be aware of depending on your budget.
Most EVSE units have the option of coming tethered i.e. a permanent flexible charging cable and appropriate connector to plug into your car. When ordering a tethered unit you will need to specify the connector to suit your vehicle. If you change your vehicle with a different connector than that on the EVSE you will need to have it changed. If you have two electric vehicles with different connector types to share one EVSE then a tethered unit will be unsuitable.
An untethered EVSE will have a Type 2 socket on the front instead of a permanently attached cable.See our article on connector types for more information on connector types. You will need to have a suitable cable to connect to the unit and your car. Remember not to leave the cable in the unit when not in use to reduce the risk of theft although some units feature the ability to lock the cable.
Smart EVSE Units
A standard EVSE will be a simple device where the car will mange the power delivery to suit the battery state of charge. There are more sophisticated units that can monitor your domestic power consumption, solar PV power output, domestic storage battery or low rate tariff power and tailor vehicle charging to the most cost effective profile. An example of this is the Energine Zappi. If you have 2 EV’s at home some units can be installed in series and balance power delivery if one car or two cars are charging.
These units allow 2 way movement of power hence the Vehicle to Grid term. These units currently have a small market as only the Nissan LEAF offers bidirectional charging. The benefit of V2G allows you to use the vehicle battery as a power reservoir, charging at a low rate and consuming that energy when rates are expensive. A number of GB based businesses are offering these dynamic charging tariffs, unfortunately no Northern Ireland based power suppliers currently offer this facility
Commercial units typically have a higher power delivery capability and other features including connecting to cloud based management systems to track power consumption, faults and authorise users charging sessions.