EV Roaming: Hubs vs Peer-to-peer Roaming

Roaming in the context of EV charging refers to the ability of an EV driver to use charging stations across different operators without the need for multiple memberships or subscriptions. This is a significant convenience factor for EV drivers, especially those who travel long distances and cross different network areas.
EV Roaming: Hubs vs Peer-to-peer Roaming

The first and foremost advantage of roaming is the ease of access it provides to EV drivers. With roaming, a driver doesn’t have to worry about whether they’ll be able to find a compatible charging station on their route. They can charge their vehicle at any station, irrespective of the operator, using a single account. This significantly simplifies the charging experience and encourages more people to opt for electric vehicles.

Roaming also extends the coverage of charging networks. By allowing interoperability between different networks, roaming effectively increases the number of charging stations available to EV drivers. This is particularly beneficial in rural or remote areas, where charging infrastructure might be sparse.

For Charge Point Operators (CPOs), expanding access to their charge points through roaming agreements with other network operators is a strategic move toward increasing utilization and profitability. Increased utilization translates to higher revenue and a better return on investment for deployed assets, thus potentially accelerating the deployment of additional charging infrastructure.

In addition, a wider user base enables CPOs to gather valuable data on usage patterns and demand, aiding in the optimization of operations and dynamic pricing strategies, further bolstering revenue generation and competitive pricing for users. Through roaming, CPOs not only enhance their financial viability but also contribute significantly to propelling the electric vehicle revolution forward.

Overview of Roaming Solutions

Roaming solutions in the Electric Vehicle charging domain aim to bridge the gap between various Charge Point Operators (CPOs) and e-Mobility Service Providers (eMSPs), facilitating a seamless charging experience for EV drivers across different networks. 

Two primary types of roaming arrangements prevail – Direct Peer-to-Peer Roaming and Roaming Hubs.

In Direct Peer-to-Peer Roaming, CPOs form bilateral agreements with eMSPs or other CPOs, creating direct connections between their systems. This setup allows EV drivers to use charging points across different networks with a single account, promoting ease of use and broadening the accessible charging infrastructure. However, the complexity increases with the number of agreements, demanding a robust management system.

On the other hand, Roaming Hubs serve as intermediaries, connecting multiple CPOs and eMSPs through a central platform. This centralized approach simplifies the management of roaming agreements and offers a broader network of accessible charge points for EV drivers. It also facilitates standardized communication, data exchange, and payment processing among the connected parties, streamlining operations and ensuring a consistent user experience.

Both Direct Peer-to-Peer Roaming and Roaming Hubs offer distinct advantages and present certain challenges, the understanding of which is crucial for making informed decisions in crafting a roaming strategy. The ensuing sections will delve deeper into the comparative analysis of these roaming solutions, shedding light on various factors like cost, coverage, functionalities, and data handling, to provide a comprehensive understanding that can guide executives in making a well-informed decision.

Peer-to-Peer Roaming

Direct Peer-to-Peer Roaming emerges as a straightforward solution for establishing connectivity between Charge Point Operators (CPOs) and e-Mobility Service Providers (eMSPs). Under this arrangement, a bilateral agreement is forged directly between parties, facilitating a seamless user experience for EV drivers across different networks.

One of the notable advantages of Direct Peer-to-Peer Roaming lies in its simplicity and directness. By establishing a direct connection, parties can work closely together to tailor the terms of the agreement to their specific needs, potentially resulting in a more favorable arrangement for both. Moreover, this direct connection can lead to faster resolution of issues, as the channels of communication are clear and well-defined.

On the downside, as the network expands and the number of agreements increases, managing these individual connections can become complex. Each new agreement demands attention in terms of negotiation, implementation, and ongoing management. This escalates the administrative burden and could potentially strain the resources of a CPO or eMSP.

Furthermore, the absence of a centralized hub means that data standards and communication protocols need to be agreed upon separately with each party, posing a risk of inconsistency in user experience and operational processes.

Despite its challenges, Direct Peer-to-Peer Roaming remains a viable option, especially for larger CPOs and eMSPs with the resources to manage multiple direct agreements. It provides a foundation for cultivating strong partnerships and ensuring that the interests and needs of the involved parties are adequately addressed. This model is particularly suited for those looking to maintain a high degree of control over their roaming partnerships and user experience.

Roaming Hubs

Roaming Hubs serve as a pivotal point in the EV charging ecosystem, facilitating seamless interactions between Charge Point Operators (CPOs) and e-Mobility Service Providers (eMSPs). By centralizing the connections, they significantly reduce the complexity associated with managing multiple bilateral agreements that would otherwise be necessary in a direct peer-to-peer roaming setup.

At its core, a Roaming Hub operates as a unified platform, bringing together multiple CPOs and eMSPs to broaden the accessibility of charging infrastructure for EV drivers. When a CPO or eMSP connects to the hub, it gains access to the charging networks of all participating CPOs, thereby significantly expanding its charging network footprint. This interconnectivity is facilitated through a standardized protocol which ensures seamless communication, data exchange, and payment processing among all entities involved.

A notable advantage of Roaming Hubs is the expanded network coverage they offer. By aggregating multiple charging networks, they significantly extend the range of accessible charge points for EV drivers, alleviating range anxiety. This extended network is especially beneficial for EV drivers who frequently travel across different regions, as it provides a more expansive and reliable charging infrastructure.

Moreover, Roaming Hubs contribute to operational efficiency. They handle the intricacies of data flow, agreement management, and invoicing on behalf of the connected parties. This centralized handling minimizes the administrative burden on individual CPOs and eMSPs, allowing them to focus more on enhancing their core offerings and improving the overall user experience.  

However, a potential downside of utilizing a Roaming Hub is the associated cost, which can vary from one hub to another. The fees imposed by the hub for facilitating these seamless interactions and transactions might be a concern, especially when considering the financial implications in the long run.

Major Roaming Hubs

There are multiple hubs that a CPO or eMSP can consider for integration, each with a slightly different focus in terms of geography or other features. These hubs cater to various aspects of the roaming ecosystem, offering tailored solutions to meet the diverse needs of CPOs and eMSPs across different regions. 


Hubject is a joint venture of leading companies in the automotive, energy, and technology sectors, including Volkswagen, BMW, and Siemens. It operates a cross-provider charging network called "intercharge," aiming to establish a standard for charging infrastructure and enable seamless charging experiences for EV drivers. The intercharge network boasts connections with over 1000 business partners in 52 countries, encompassing more than 400,000 charge points​​.


Gireve is an open platform that connects EV charging networks and service providers. It offers tools and services to support the interoperability of charging networks, ensuring that EV drivers can access a wide range of charging points with a single subscription. Gireve's platform has connected over 400,000 charge points across Europe and processes more than 1,000,000 transactions per month.


E.Clearing operates as a central roaming platform that connects charging point operators and e-mobility service providers, ensuring seamless cross-border charging for EV drivers. It provides a standardized protocol for communication, facilitating the exchange of authorization, transaction, and charge detail records between parties. Its pricing, based on the number of charge points or charge cards, is publicly available on the company website.


ChargeHub is a platform that aggregates charging station information and provides EV drivers with real-time availability, pricing, and user reviews for more than 150,000 charging stations across North America. It aims to simplify the EV charging experience by offering a comprehensive database of charging stations, along with a mobile app for easy station location and navigation​​. In addition, ChargeHub extends roaming hub services, facilitating seamless interactions between charging point operators and e-mobility service providers.

Choosing a Roaming Solution

The process of selecting a roaming solution is crucial for CPOs and eMSPs as it significantly impacts the user experience, operational efficiency, and profitability. Below are some key considerations while evaluating different types of roaming solutions.

Evaluating Hubs

Coverage: Check the geographical reach of the hub and the number of charging points accessible through it. It's vital that the hub provides adequate coverage in the regions where your users frequently travel.

Cost: Assess the pricing model, including the setup, integration, and transaction fees. A transparent and predictable pricing structure is desirable.

Functionalities: Evaluate the functionalities provided by the hub, such as real-time availability checking, reservation capabilities, and dynamic pricing.

Payment Handling and Administration: Look at how the hub handles payment processing, invoicing, and settlement. Efficient administration tools for managing roaming agreements and dispute resolution are also critical.

Data Flow and Integration Complexity: Assess the ease of integration with your existing systems and the flow of data for authorization, transaction, and charge detail records.

Evaluating Direct Roaming Solutions

Number of Agreements: Consider the number of agreements you'll need to form and manage with other CPOs or eMSPs. The administrative burden can increase with the number of direct agreements.

Cost: Assess the cost involved in setting up and managing direct roaming agreements, including any necessary upgrades to your CSMS and other systems.

Integration Complexity: Evaluate the technical challenges in integrating direct roaming solutions with your existing systems.

Standardization: Check if the direct roaming solution adheres to standardized communication protocols, which can ease integration and operation.

Recommendations for Stakeholders

Informed Decision-Making: Leverage the comparative analysis and evaluation criteria discussed to make informed decisions when opting for a roaming solution.

Engage with Industry Experts: Engaging with industry experts, participating in forums, and networking with peers in the EV charging ecosystem can provide valuable insights.

Continuous Learning and Adaptation: The EV roaming landscape is continuously evolving. Stay updated with the latest trends, technologies, and regulatory developments to ensure your roaming solutions remain competitive and compliant.


The electric vehicle (EV) charging landscape is evolving rapidly, with roaming solutions at the forefront of enhancing user experience and operational efficiency. This article provides a glimpse into the dynamic world of EV roaming, shedding light on its importance, different roaming solutions, major roaming hubs, and the considerations involved in choosing a suitable roaming solution. 

For an in-depth understanding and a detailed analysis, we recommend reading our full guide, "Ultimate Guide to EV Roaming: The Executive Playbook," and our whitepaper, "Ready To Roam: Your Guide To EV Roaming Success."

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