How to prepare the home electrical system for electric car?
Understanding Home Connection Power
Each household has a certain power of the electrical connection, usually oscillating around 15 kWh. This means that the sum of the power of all simultaneously used appliances should not exceed this value. For example, using a 1kW kettle, we use one fifteenth of the available power.
Choosing a Charger for an Electric Car
Depending on whether the electric car has a 1-phase or 3-phase charger (and its power, such as 3.7/7.4/11kWh, etc.), the home charger and connection power should be adjusted accordingly. You can check the power of the car's on-board charger in the car's manual.
Various types of chargers are available, including:
Socket, 1-phase 16A - 3.7 kW
Forced, 1-phase 32A - 7.4 kW
Forced, 3-phase 16A - 11 kW
Forced, 3-phase 32A - 22 kW
Adjustment of Connection Power
With connection powers typical for single-family homes (e.g., 15 kW), the choice of charger is crucial. For example, using a 7.4 kW 1-phase charger, we exceed the available power on one phase (5 kW), which requires adjusting the connection power.
Selection of Installation Cables
Based on the amperage of the selected charger and the length of the cable from the switchgear, an electrician with appropriate qualifications should select the conductor cross sections of the wires. The minimum values are:
For 16A: 2.5mm
For 32A: 6mm
Protection
It is recommended that the electric car charger be connected to a dedicated electrical circuit with protection:
S-type overcurrent for each phase (16/32A fuse, characteristic B)
Differential-current (RCD Type A) with DC detection
6 Importance of Grounding
Most chargers require a properly functioning grounding. Some models may also fail to operate if the phase and neutral wires are swapped places.
Additional Aspects to Consider
Planning for future needs: Consider increasing the power connection beyond current needs to provide flexibility for the future.
Smart energy management systems: These solutions can optimize energy consumption, especially when using other devices with high power consumption.
Use of renewable energy: Installing solar panels can increase energy independence and reduce the load on the grid when charging the car.
Consideration of local conditions: The specifics of electrical installation may vary depending on local regulations and standards.
Summary
Preparing a home's electrical system to support an electric car requires prudent planning. This includes understanding the available connection power, choosing the right charger, adjusting the installation, and ensuring safety through proper protection and grounding. It's also worth thinking about future needs and the potential use of renewable energy.