V2G (Vehicle-to-Grid):
An electric car as an industrial storage device

The corporate electric car is idle 95% of the time. At this time, its battery -- tens of kilowatt-hours of stored energy -- is doing nothing. V2G (Vehicle-to-Grid) technology and its variations make it possible to turn a car fleet into a distributed mobile power plant integrated into the enterprise's energy system. For Ukrainian business in conditions of generation shortages and regular outages, this is not a futuristic concept, but a practical tool for reducing costs and increasing energy security.

The essence of technology: Battery on wheels

A modern electric car has a traction battery with a capacity of 40 kWh (Nissan Leaf) to 131 kWh (Ford F-150 Lightning). For comparison, an industrial BESS rack for 100 kWh costs $20,000 - $30,000. If you have 5-10 electric vehicles in your fleet, you already have the equivalent of an industrial energy storage system -- the only question is how to use this energy.

Bidirectional charging allows you not only to charge the car from the network, but also to take energy back - to the socket, to the building or to the power grid. This requires a special charger and a car that supports the appropriate protocol.

Bidirectional charging types: V2L vs V2H vs V2B vs V2G

The abbreviation "V2X" combines four levels of integration of the electric vehicle with the energy system. Each level has its own complexity, cost and regulatory requirements:

Energy flow in a V2B system

Bidirectional arrows show the possibility of energy transfer in both directions

Standards and protocols

Bidirectional charging does not work on any electric vehicle or any charging device. Support for the appropriate protocol on both sides is required. Here are the main standards:

CHAdeMO

The Japanese standard for fast DC charging, which was the first to implement bidirectional energy transfer back in version 1.0 (2010). Nissan Leaf is the most common V2G-ready car in the world thanks to CHAdeMO. The protocol supports power up to 400 kW (CHAdeMO 3.0 / ChaoJi), but typical V2G power is 6-10 kW. Disadvantage: CHAdeMO is gradually being replaced by the CCS standard in Europe and North America. However, it remains dominant in Japan and parts of Asia.

CCS (Combined Charging System) / ISO 15118-20

The ISO 15118-20 standard, published in 2022, added support for bidirectional energy transfer to the CCS protocol for the first time. This means that new models of CCS port (most European and American EVs) will be able to support V2G. Hyundai, BMW, Volkswagen, Ford and others have already announced firmware updates for their models. ISO 15118-20 also supports Plug&Charge (automatic authentication without a card) and smart charge management based on tariff signals.

OCPP 2.0.1 (Open Charge Point Protocol)

This is a communication protocol between the charging station and the central management system (CSMS). Version 2.0.1 added support for V2G scenarios: the charging station can receive commands to discharge the vehicle from the building's EMS or the grid operator. For B2B integration, OCPP 2.0.1 is a mandatory protocol that allows you to manage dozens of charging points through a single interface.

Battery capacity of popular EVs

To assess the potential of V2B/V2G, it is important to understand how much energy is actually available in the batteries of the most common electric vehicles:

Connection diagram: AC Coupling vs DC Coupling

When integrating V2B of an existing BESS or solar power plant, there are two architectural approaches:

AC Coupling

The charging station has a built-in inverter and outputs alternating current (AC) directly to the building bus. This is a simpler option, compatible with any existing wiring. Each component (BESS inverter, V2G charging station, solar inverter) operates independently on a common AC bus. The disadvantage is a double conversion (DC-AC-DC) when charging a stationary BESS from an EV, which gives losses of 8-12%.

DC Coupling

The charging station is connected directly to the DC bus of the hybrid inverter or the DC bus of the stationary BESS. This is a more efficient option (2-5% loss), but requires equipment compatibility and more complex design. Suitable for new objects where the system is designed from scratch. Manufacturers such as SMA and Victron Energy already offer DC-input hybrid inverters for V2G.

Impact on the electric vehicle battery

One of the most common concerns about V2G -- does the EV battery wear out from the extra cycling? This is a legitimate question and the answer is based on real research.

What the research says

Research University of Warwick (UK, 2023) showed that V2G can even extend battery life if smart charge management is used. The reason: instead of keeping the battery at 100% SOC (State of Charge) overnight, V2G discharges it to 50-70% and maintains the optimal SOC range, which reduces degradation from calendar aging.

Research Idaho National Laboratory (INL, USA, 2024) based on 5,000 Nissan Leafs with V2G showed an additional degradation of only 1-2% over 5 years with a daily V2G cycle of 30% SOC depth. For comparison, the usual degradation of the Leaf battery is 15-20% in 5 years.

"With proper SOC management (keeping the battery in the 20-80% range), V2G adds minimal wear and tear. Your car still degrades over time -- it's just a question of whether it's making money doing it." -- Dr. Kotub Uddin, WMG, University of Warwick.

Recommendations for minimizing wear

• Limit V2G bit depth: Do not discharge below 20% SOC and do not charge above 80% (unless full capacity is required for the trip).
• Limit C-rate: Use a moderate discharge capacity (0.3C-0.5C), which for a 77 kWh battery means 23-38 kW.
• Temperature management: Do not use V2G when the battery temperature is above 40 C or below -10 C.
• Smart planning: The EMS must consider the travel schedule and guarantee the minimum necessary SOC for the next trip.

Real cases in the world

Nissan / Enel X -- Great Britain and Denmark

One of the largest V2G pilot projects in the world. Enel X has installed more than 1,000 bidirectional charging stations for the Nissan Leaf in the UK and Denmark (2020-2024). Owners of EVs received payment for participation in balancing the network (frequency response). Verified Financial & Technical Results: The average owner earned 400-600 GBP per year from V2G, with additional battery degradation of less than 1% per year. In 2024, the project was expanded to include commercial Nissan e-NV200 fleets.

Honda is a V2G pilot in Japan

Honda has launched a V2G pilot in the city of Sakurai (2023-2025) using the Honda e and its own bi-directional charging stations. The feature is the integration of home solar panels and stationary BESS Honda Power Manager. The system automatically selects the optimal energy source: solar panels (if it is daytime), car battery (if the car is connected) or the network (as a last option).

Utrecht (Netherlands) is the largest V2G hub in Europe

The city of Utrecht has created Europe's largest V2G hub of more than 500 bidirectional charging points (We Drive Solar + Renault). The municipal fleet of Renault ZOE and Renault Megane E-Tech electric vehicles is used to balance the local network and power municipal buildings. Key result: a 25% reduction in the peak load on the local substation, allowing for the postponement of an expensive transformer upgrade.

Hyundai Ioniq 5 -- V2L in Ukraine

Although full-fledged V2G has not yet been implemented in Ukraine, the V2L function on the Hyundai Ioniq 5 is actively used by Ukrainian owners of 2022 years. During mass blackouts, the Ioniq 5 of a 77.4 kWh battery could power a refrigerator, lighting, a router, and charge phones for 2-3 days. This demonstrated the practical value of "battery on wheels" in military realities and became a catalyst for interest in V2H/V2B solutions in the corporate sector.

Financial model: ROI for a fleet of 10 EV

Let's consider a realistic business case for a logistics company in Kyiv with a fleet of 10 electric vans (total battery capacity -- 770 kWh):

* The calculation does not take into account the additional value of backup power during blackouts. If you include the cost of business downtime during outages (an average of $500-2,000 per hour for a medium-sized enterprise), the payback period can be reduced to 2-3 years.

Regulatory status in Ukraine

As of the beginning of 2026 years, the regulatory environment for V2G in Ukraine is at an early stage of formation:

Net Metering (Net accounting)

The Law of Ukraine "On the Electric Energy Market" provides for a net metering mechanism for household consumers of generation (solar panels). However, this mechanism does not currently apply to V2G -- meaning you cannot legally sell the car's electricity back to the grid at a "green tariff". For V2B (powering your own building) there are no such restrictions - this is internal consumption.

The position of the NCRECP

The National Commission for State Regulation of Energy and Utilities (NKREKP) has not yet issued a separate regulatory act regarding V2G. However, as part of the Energy Service Contracts (ESCO) program and Smart Grid initiatives, the inclusion of bidirectional charging as an element of demand response is being discussed. It is expected that the first regulatory documents will appear in 2026-2027.

What can be done now

• V2L: Completely legal. You simply use the electric car as a portable generator.
• V2H: Legally as a backup power supply (similar to a generator). Does not require permissions if there is no return flow to the network.
• V2B: Legal with the correct connection scheme (with AVR, which excludes the return flow to the network). In terms of legal status, it is equivalent to a diesel generator.
• V2G: Requires individual agreement of the distribution network operator (oblenergo). De facto not implemented in Ukraine.

V2G in Ukraine: Reality or fiction?

Full-fledged V2G (energy sale to the network) for Ukraine is the horizon of 2027-2030 years. But V2B (powering your own building) is already a reality today. Considering the generation deficit and the predicted blackouts for the winter seasons, we see a boom in corporate V2B solutions in the next 2-3 years. It is cheaper than buying a stationary BESS if you already have or plan to have a fleet of electric vehicles.

Conclusions of BESS Ukraine

If you are planning to update your corporate fleet, choose models with support for bidirectional charging (standard ISO 15118-20 or CHAdeMO V2G). This is an investment that turns a liability (a car in the parking lot) into an asset (an element of the company's energy system). Even if you don't plan on V2G now, having a bi-directional port in your car is a future-proof option that costs nothing to buy.

We recommend starting a V2B pilot with 2-3 vehicles and one bidirectional charging station to assess the real savings in your business environment.

Frequently Asked Questions about V2G

Does Tesla support V2G?

As of early 2026 years, Tesla does not officially support V2G or V2H through its proprietary port (NACS) and protocol. The Tesla Powerwall can work as a stationary BESS, but Tesla cars cannot feed power back through the charging port. In 2024, Tesla announced the "Cybertruck as a Generator" of the V2H function, but the full implementation is still delayed. For V2B/V2G, we recommend considering the Nissan Leaf, Hyundai Ioniq 5, Ford F-150 Lightning or VW ID. series of CCS ISO 15118-20.

How much does a bidirectional charging station cost?

Prices vary by capacity and protocol. Wallbox Quasar 2 (7.4 kW, CHAdeMO/CCS) -- $4,000-6,000. dcbel r16 (15.2 kW, CCS, of solar panel integration) -- $10,000-12,000. Fermata Energy FE-20 (20 kW, CCS, industrial grade) -- $15,000-20,000. For V2B of park 5-10 EV charging infrastructure budget will be $25,000-80,000 depending on configuration. To this is added the cost of EMS, AVR and electrical installation works ($10,000-20,000).

Does using V2G void the car's warranty?

It depends on the manufacturer. Nissan officially supports V2G for the Leaf and e-NV200 and does not void the battery warranty when using certified charging stations. Hyundai allows V2L without restrictions, but the position on V2G via CCS is still being clarified. Ford guarantees the F-150 Lightning's battery even when using Intelligent Backup Power (V2H). General rule: use only certified equipment from vehicle manufacturer partners and keep documentation of all V2G sessions.

Can V2B be combined with stationary BESS and solar panels?

Yes, and this is the optimal configuration. Stationary BESS provides base storage and peak shaving 24/7, solar panels generate cheap power during the day, and V2B adds flexibility and additional capacity during peak load hours. EMS coordinates all three sources. For example: During the day, the solar panels power the building and charge both the BESS and the EV. In the evening, when the tariff increases, the building switches to BESS. If the BESS is depleted and the peak is not yet over, EVs are connected via V2B. At night, everything is charged from the network at a cheap rate.

What happens during a blackout? Can V2B work autonomously?

Yes, if there is an AVR (automatic reserve input) or a manual switch. When the mains power goes out, the AVR isolates the building from the mains (island mode) and switches the power to the charging station / EV. Important: the charging station must support island mode (not all models can do this). Wallbox Quasar 2, Fermata FE-20 and dcbel r16 support island mode. In this mode, 5 connected EVs (total capacity 385 kWh at 20-80% SOC) can power an average office (15-20 kW) for 19-25 hours.