March 31, 2026
Zhang, F., Tang, J., Qian, B., Xiao, Y., Lin, X., & Feng, X. (2025). V2G Charging Stations: A Comprehensive Review of Technology and Infrastructure. China Journal of Electrical Engineering (forthcoming).
Study Purpose
This paper takes a different approach than most V2G research. Instead of focusing on market value or system-level benefits, it examines the infrastructure that makes V2G possible, specifically the charging systems that sit between the vehicle and the grid.
The core question is practical: what does it actually take to move energy back and forth between vehicles and the grid in a way that is reliable, controllable, and scalable?
To answer that, the authors walk through how V2G systems are built and how they operate in the real world. They examine not just the vehicle, but the full system, including the charger, control software, communications, and grid interface. The result is a grounded view of V2G as an engineered system, not just a concept.
Study Method
This paper is a systematic technical review of vehicle-to-grid charging infrastructure, synthesizing prior research rather than presenting new experimental results.
The authors organize the literature around a structured framework that moves from system-level architecture to component-level design and control strategies. Specifically, the review integrates findings across several domains:
- System architecture and operating principles, drawing on existing studies to describe how vehicles, chargers, aggregation platforms, and grid systems interact
- Power electronics and hardware design, including comparative analysis of inverter topologies, conversion approaches, and component configurations
- Control strategies and optimization methods, ranging from classical control (PI/PID) to advanced approaches such as model predictive control and reinforcement learning
- Communication and interoperability standards, including protocols like ISO 15118 and OCPP
- Application use cases and system value, synthesized from prior demonstrations and field deployments
Rather than evaluating a single dataset or pilot, the study compares and categorizes existing research, often organizing findings into typologies (for example, single-stage vs two-stage converter designs, or different control strategies) and summarizing their performance, tradeoffs, and application contexts.
In this sense, the methodology is best understood as a structured literature synthesis with a strong engineering lens, designed to connect component-level design choices to system-level performance and real-world application.
Study Results
The most important takeaway from this study is simple but important: V2G is not just about enabling energy to flow both ways. It is about building systems that can do that reliably, at scale, and in coordination with the grid.
At the center of this is the bidirectional charger. The paper makes clear that this device is doing much more than charging a battery. It is continuously converting power, managing voltage and current, and responding to signals from both the grid and the vehicle.
One useful insight, without getting too deep into engineering detail, is that not all V2G chargers are built the same. Some designs are simpler and lower cost, making them a better fit for residential applications. Others are more complex and flexible, allowing them to operate at higher power levels and respond more precisely to grid needs. The tradeoff is straightforward: simplicity and cost on one end, performance and flexibility on the other.
More important than the hardware itself is how these systems are controlled. The paper highlights that effective V2G depends on real-time decision-making. Chargers must continuously adjust charging and discharging based on grid conditions, electricity prices, and the status of the vehicle. This includes factors like state of charge, battery health, and the driver’s mobility needs.
This leads to one of the most important conclusions in the paper: V2G is fundamentally a coordinated system. The charger, the vehicle, and the grid are all exchanging information and adjusting behavior in real time.
The paper also reinforces the range of services V2G can provide. These include reducing peak demand, absorbing excess renewable generation, stabilizing voltage and frequency, and even providing backup power during outages. In each case, the value comes from the ability to control when and how energy moves between the vehicle and the grid.
Finally, the study highlights a practical reality that often gets overlooked. The performance of V2G is not uniform. It depends on how the system is designed, how it is controlled, and how well it is integrated with the grid. That variability is one of the key challenges the industry still needs to address.
Limitations of the Study
While the paper provides strong technical insight into how V2G charging systems work, it remains focused on engineering design rather than real-world deployment.
It relies largely on academic research and modeled performance, with limited evidence from large-scale operational systems. As a result, it does not fully capture how these technologies perform under real-world conditions, including customer behavior, distribution system constraints, and program design.
The discussion of policy, market structure, and compensation is also relatively limited. These factors are often the primary drivers of whether V2G is deployed at scale.
Finally, the paper treats V2G largely on its own, with less attention to how it works alongside managed charging and other flexible demand resources. In practice, these approaches are likely to evolve together.
Implications for the V2G Industry
For the V2G industry, the value of this paper is not in the technical detail itself, but in what that detail reveals about the path to scale.
First, it reinforces that infrastructure is foundational. The bidirectional charger is not just hardware. It is the control point where vehicles, markets, and grid operations intersect. Design choices at this layer will directly shape system performance, cost, and scalability.
Second, it makes clear that V2G is a system-level capability. Value does not reside in the vehicle or the charger alone, but in how those components are coordinated through software, communications, and integration with grid operations.
Third, the paper highlights that performance will vary across implementations. Differences in hardware design, control strategies, and system integration will lead to materially different outcomes. This has direct implications for program design, interconnection requirements, and how regulators and utilities define and measure performance.
Finally, the study reinforces a broader industry transition. The question is no longer whether V2G can work. The question is whether it can be delivered reliably, interoperably, and at scale.
Achieving that outcome will depend as much on infrastructure design and system integration as it does on the vehicles themselves.
