What is Vehicle-to-Grid (V2G)

Turning EV Charging into a Revenue and Energy Asset.

Vehicle-to-Grid (V2G) technology transforms EV charging from a simple energy transaction into a strategic energy asset. For you as a Charge Point Operators (CPOs) and eMobility Service Providers (EMPs), it means: 

• New revenue streams from grid balancing and flexibility markets.
• Smart grid management and sustainable performance leading to reduced energy costs.
• Enhanced driver experience through greater control over V2G charging schedules and battery status.

 
By enabling bidirectional charging, V2G allows stations not only to draw power from the grid but also to feed energy back, supporting energy stability and unlocking economic value. 
 

In this guide we will cover:

1. What is Vehicle-to-Grid(V2G)
2. Why V2G Matters
3. How V2G Works
4. Frequently asked questions

Let's start:

1. What is Vehicle-to-Grid (V2G)?

Vehicle-to-Grid (V2G) is an advanced charging technology that enables bi-directional power flow between an electric vehicle battery and the electricity grid. 

When connected to a V2G-capable charging station, the EV battery can either:

• Charge from the grid during periods of low electricity demand, or
• Discharge back to the grid (or local building) when demand is high

 
2. Why V2G Matters

• For the Energy Transition 
  As the demand of the electricity grows without increasing the energy production, the grid faces volatility. V2G bridges this gap by utilising existing EV batteries as distributed energy storage assets, storing power from renewable sources and supplying it back to the grid when needed.  
• For the eMobility Business 
  EV adoption is accelerating, with over 250 million EVs expected globally by 2030. Each one represents potential storage capacity, and thus, market value. For EMPs and CPOs, this means:
• New revenue models from grid services and energy trading.
• Differentiated offerings for fleets, workplaces, and real estate owners.
• V2G reduces OPEX for fleets as they utilises the EV batteries when they are not in use to generate additional revenue 
   
• For Cost and Carbon Savings

Vehicle-to-Grid (V2G) technology helps maintain stable and efficient grid operations, reducing the need for additional energy purchases from fossil fuel–based producers.  
 
The results: Improved grid reliability, new revenue streams by participating in energy markets, reduced electricity bills, and lower emissions. 
 

3. How V2G Works

Requirements 

• Country legislation enabling V2G operations.
• V2G-enabled charging stations.
• Electric vehicles compatible with bidirectional charging technology.
• Sufficient number of connected EVs to meet the minimum bid capacity required by the electricity market. 
  For example, in Finland, Fingrid’s FCR-N market requires a minimum bid size of 0.1 MW (100 kW).

When an EV equipped with bidirectional charging technology is connected to a V2G charging station, the driver sets a target state-of-charge and an estimated departure time. The system then calculates how much energy the vehicle can safely supply back to the grid when requested, ensuring that the EV reaches the desired battery level by the time the driver plans to depart.

We recommend maintaining target charge levels between 70% and 90% to support efficient energy management and battery health. The EV drivers or driver or  fleet managers have full control to define their preferred settings. 
 
Note: 
Please note that V2G operation is not possible when the battery is fully charged.
 

4. Frequently Asked Questions

 1. What infrastructure is required to support V2G? 
You need:

• Country legislation enabling V2G operations.
• V2G-enabled charging stations.
• Electric vehicles compatible with bidirectional charging technology.
• Sufficient number of connected EVs to meet the minimum bid capacity required by the electricity market.
• A secure communication protocol, typically ISO 15118-20 for bi-directional data flow.

2. What communication standards does V2G rely on? 

V2G relies on standardised communication protocols to ensure interoperability between electric vehicles, charging stations, and grid systems. The key global standard is the ISO 15118-20 certificate, which defines the communication framework for bidirectional charging between EVs and charging equipment.

Additionally, the Open Charge Point Protocol (OCPP) facilitates communication between charging stations and backend management systems. While OCPP 1.6 provides support, the OCPP 2.0.1 version will also support V2G functionalities in the near future.

3. Can V2G be used with both AC and DC charging stations? 
Yes. However, it depends on the manufacturer's station model and capability for bidirectional charging. Currently, most V2G use cases operate on DC charging stations.

4. What are the regulatory or compliance requirements? 
Regulations vary by country, but typically require:

• Certification for grid-interactive devices.
• Participation in national demand response or flexibility markets.
• Adherence to energy metering and data privacy standards (e.g., GDPR in the EU).

5. Can existing charging stations be upgraded to support V2G? 
Only if they are hardware-ready (bi-directional capable), otherwise, new units are required. Software upgrades may enable communication features, but power electronics must support two-way flow.

6. Are there interoperability challenges between different Original Equipment Manufacturers (OEMs) and charging stations? 
Yes, interoperability is still evolving. The ISO 15118-20 and CCS V2G implementation will unify communication between most EV brands, simplifying cross-network compatibility.

7. How can I, as a CPO or EMP, prepare for commercial V2G adoption now?

You will need to:

• A minimum of 20 V2G charging stations is recommended to adequately support and cover the required grid capacity.
• V2G-compatible electric vehicles.
• Collect data on session behaviour and idle time to model V2G potential.
• Ensuring that V2G operations are enabled and supported in your country. 

We will take care of all the complexities. If you have any questions or require further guidance, please reach out to your Customer Success Manager or contact our Sales.

That's it, you now know what V2G is, how it adds value to eMobility service providers and charge point operators by:

• Securing a first-mover advantage in smart energy services.
• Building resilience and profitability into EV infrastructure.
• Enabling a cleaner, more balanced energy future.
• And how it works. 

V2G is not just about charging cars; it’s about powering the future.