A driver expects one app or card to work almost everywhere. Behind that expectation sit thousands of commercial relationships between charging networks and e-mobility providers. Signing and integrating each of them individually would be impossible for most companies. Roaming hubs solve this by acting as a central marketplace and switchboard.
This guide explains what roaming hubs do, how they differ from direct connections and how to build a roaming strategy that fits your network.
- A roaming hub lets a CPO or eMSP connect once and reach many partners.
- Hubs route authorisations, sessions and charge detail records and often handle contracts and financial clearing.
- Direct peer-to-peer OCPI connections avoid hub fees and give more control, but need effort per partner.
- Most networks combine a hub for reach with direct links to their biggest partners.
Why roaming needs hubs
With 100 charge point operators (CPOs) and 100 e-mobility service providers (eMSPs), full peer-to-peer coverage would require up to 10,000 bilateral integrations and contracts. A hub reduces this to 200 connections. Each party integrates once, then activates partners through the hub's agreements. The two roles involved are explained in our guide to CPO vs eMSP.
What a roaming hub does
| Function | Description |
|---|---|
| Data exchange | Routes locations, tariffs, tokens, sessions and charge detail records between parties |
| Real-time authorisation | Forwards authorisation requests from a CPO to the driver's eMSP and returns the answer |
| Contract management | Provides standard agreements or a marketplace where parties accept each other's terms |
| Clearing and settlement | Some hubs reconcile charge detail records and handle invoicing or payment between parties |
| Data quality checks | Validates formats and flags inconsistent locations or records |
Protocols used by hubs
Hubs use different protocols. Some are built on OCPI, the open protocol maintained by the EVRoaming Foundation. Others use their own protocols, such as OICP, created for Hubject's platform. Several hubs support more than one protocol. Our guides to OCPI and OICP explain both, and our article on OCPI 2.2.1 modules covers the technical details.
Examples of roaming platforms
Well-known roaming platforms in Europe include Hubject, Gireve and e-clearing.net, each with different geographic focus, protocols and commercial models. Coverage, partner lists and fees change over time, so compare current offers before deciding.
Hub vs peer-to-peer
| Aspect | Roaming hub | Peer-to-peer OCPI |
|---|---|---|
| Integration effort | One integration, many partners | One integration per partner |
| Contracts | Standardised through the hub | Negotiated bilaterally |
| Fees | Connection and/or per-session fees | No hub fees |
| Control and data | Hub sits in the middle | Direct relationship and data |
| Speed to scale | Fast | Slower |
| Best for | Reach, long tail of partners | Large, strategic partners |
Costs to expect
Hub pricing typically combines an annual or monthly platform fee with transaction-based fees per session or per kWh. Some hubs charge both CPOs and eMSPs, others only one side. Add your own implementation and testing effort, and the cost of reconciling records. Model these costs against the extra revenue roaming brings; for many sites, roaming is one of the most effective ways to increase utilisation.
Building a roaming strategy
- Define your goal: more drivers at your chargers (CPO), more coverage for your customers (eMSP) or both.
- Map your partners: which eMSPs do your drivers use? Which networks do your customers want?
- Start with reach: a hub quickly connects you to many partners.
- Add direct links: once volumes with a few partners grow, consider direct OCPI connections to save fees and gain control.
- Keep data clean: partners show your locations, tariffs and availability to their users. Wrong data damages your reputation in other companies' apps.
- Reconcile carefully: compare CDRs with your own session data every month, especially in the first months with a new partner.
Technical requirements for your platform
- Support for the protocols and versions your chosen hubs and partners use.
- Correct mapping of your sites, EVSEs and connectors, including EVSE IDs.
- Real-time authorisation with low latency, plus offline whitelists for resilience.
- Tariffs that can be published exactly as they are charged.
- Logs of every roaming message to resolve disputes.
Frequently asked questions
Do I need a roaming hub to offer roaming?
No. You can connect directly to partners using OCPI. A hub simply makes it faster to reach many partners at once.
Can I connect to more than one hub?
Yes. Many networks connect to several hubs to cover different regions or partner groups, and combine them with direct links.
Who sets roaming prices?
The CPO sets the price it charges the eMSP, based on bilateral or hub agreements. The eMSP then sets the price for its own driver.
How long does it take to go live with a hub?
It depends on your platform and the hub's onboarding process. With a platform that already supports the hub's protocol, the main work is configuration, testing and contracts.
Connect your chargers to roaming hubs and direct partners through OCPI from one platform, with full roaming logs. See Üreticy's roaming features or contact us.
Roaming Hub Integration Challenges and Solutions
Integrating an EV charging network with a roaming hub can present several challenges, especially for smaller operators or those new to the market. One of the primary challenges is ensuring that your charging stations are compatible with the protocols and standards used by the roaming hub. This often requires a thorough review of the technical requirements and potential modifications to your charging infrastructure. Another challenge is the complexity of data management, including ensuring secure and reliable data transmission between your charging stations and the roaming hub.
To address these challenges, it is crucial to work closely with the roaming hub provider to understand their specific requirements and technical specifications. This may involve conducting a technical audit of your existing charging stations to identify any compatibility issues. Additionally, investing in robust data management tools and protocols can help streamline the integration process and ensure that all data is accurately and securely transmitted.
Another solution is to leverage the expertise of third-party integration specialists who can help navigate the technical complexities and ensure a smooth transition. These specialists can provide valuable insights and assistance in customizing your charging network to meet the requirements of the roaming hub, thereby reducing the risk of integration issues and downtime.
Maximizing Benefits of Roaming Hubs for EV Charging Network Operators
While integrating with a roaming hub offers numerous benefits, such as increased visibility and access to a broader network of charging stations, it is essential for EV charging network operators to strategically leverage these benefits to maximize their return on investment. One key strategy is to focus on customer experience and satisfaction. By ensuring seamless and reliable charging experiences across multiple networks, operators can enhance their reputation and attract more users to their charging stations.
Another approach is to explore revenue-sharing models and promotional partnerships with the roaming hub provider. These partnerships can provide additional revenue streams and marketing opportunities, helping to offset the costs associated with integration and maintenance. Operators should also consider leveraging the data and analytics provided by the roaming hub to gain deeper insights into usage patterns and customer behavior. This data can be used to optimize the placement and functionality of charging stations, thereby improving efficiency and user satisfaction.
Lastly, it is important for operators to continuously monitor and adapt to changes in the EV market and technology landscape. This includes staying updated on new protocols, standards, and innovations in EV charging infrastructure. By remaining flexible and proactive, operators can ensure that their charging networks remain competitive and well-positioned to meet the evolving needs of EV users.