Choosing a bidirectional EV Charger depends on several technical and economic criteria. Here are the main elements to consider, along with concrete figures:
Compatibility with your vehicle
Not all electric cars support bidirectional charging. Currently, some models, such as the Renault 5 and the KIA EV6, support V2G (Vehicle-to-Grid) or V2H (Vehicle-to-Home) technology, primarily via the CHAdeMO standard. The CCS standard is beginning to integrate this functionality, but remains less widespread. Always check your vehicle's compatibility before investing.
Charging and Discharging Power
The power of a bidirectional station directly influences the charging speed and the amount of energy you can return.
- Charging power: between 7 kW and 22 kW in alternating current (AC) or up to 50 kW in direct current (DC). - Discharge power (V2H/V2G): generally 3.7 kW to 10 kW, which can power an entire house for several hours.
Example: A 10 kW bidirectional EV Charger can power an average household consuming 2 kW continuously for approximately 5 hours with a 50 kWh battery.
Features and smart energy management
The most advanced bidirectional EV Chargers incorporate features to optimize energy management:
✔ Time-based programming to take advantage of off-peak hours, when electricity costs 30 to 50% less.
✔ Real-time monitoring via a mobile app, with consumption and grid feed-in statistics.
✔ Connection with solar panels: For example, a 6 kWp solar installation can generate up to 8,000 kWh/year, some of which can be stored in the car and reused in the evening.
Standards and Certifications
A EV Charger must comply with certain safety and performance standards:
- ISO 15118: communication protocol for smart charging and bidirectionality.
- CE and IEC 61851 standards: compliance with European standards for EV charging.
- Electrical safety: protection against overvoltages and short circuits.
Installation and compatibility with your electrical network
- Required voltage: some EV Chargers operate on single-phase (230V) and others on three-phase (400V).
- Required circuit breaker: a 7 kW EV Charger requires a 32A circuit breaker, while a 22 kW station may require up to 40A three-phase.
- Installation cost: installing a bidirectional EV Charger generally costs between €1,500 and €3,500, depending on the complexity of the work.
Budget and Profitability
The price of a bidirectional EV Charger ranges from €4,000 to €8,000, or two to three times more expensive than a conventional station. However, this expense can be offset by:
- Energy savings: By charging during off-peak hours (€0.12/kWh) and consuming stored energy during peak hours (€0.25/kWh), a station can generate savings of up to €400-600 per year.
- V2G revenue: By participating in network support programs, you can resell electricity and receive financial compensation of €200 to €500 per year, depending on the rates applied by your supplier.