Vehicle-to-Grid (V2G)

Vehicle-to-Grid (V2G)

Vehicle-to-Grid (V2G) describes the bidirectional connection between electric vehicles (EVs) and the power grid. In this setup, electricity can not only be charged into the vehicle but also fed back into the grid when needed. This turns electric vehicles into mobile energy storage systems and active components of the energy system.

How it works

A V2G-enabled electric vehicle is connected to a bidirectional charging station. Unlike conventional chargers, these systems allow electricity to flow both into and out of the vehicle battery.

Electricity stored in the vehicle can therefore be returned to the grid — for example during periods of high demand or to supply a building.

The process is controlled by an Energy Management System (EMS) that intelligently schedules charging and discharging processes based on factors such as:

• grid conditions
• electricity prices
• PV generation
• mobility requirements of the vehicle

Typical applications

• Using company EV fleets as temporary energy storage systems
• Supporting the power grid by feeding electricity back during peak demand
• Combining with PV systems to increase self-consumption
• Participation in electricity markets or balancing energy markets
• Supplying buildings in island mode (e.g. during power outages)

Key figures

• Bidirectional charging power (kW): typically 3.7–11 kW (AC) or >20 kW (DC)
• Vehicle battery capacity (kWh): usually 40–100 kWh
• Battery cycle life: important for evaluating the impact on battery lifespan
• Revenue potential (€): possible through electricity trading or peak load shaving
• Vehicle downtime: availability window for energy system integration

Summary

Vehicle-to-Grid expands the role of electric vehicles beyond mobility by turning them into flexible, decentralized storage units within the energy system.

For companies with electric vehicle fleets, V2G offers new opportunities to reduce energy costs, support grid stability, and integrate renewable energy sources. Although large-scale market adoption is still developing, early pilot projects already demonstrate strong potential for commercial and municipal energy systems.

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