OCPP Explained:

1. What OCPP is

OCPP (Open Charge Point Protocol) is an application-level communication standard between an EV charging station and a central management system, usually called a CSMS (Charging Station Management System). It defines the messages a charger and a platform exchange: authorising a user, starting and stopping a session, reporting meter values, pushing firmware updates, applying load limits, and so on.

The everyday analogy: think of OCPP as the email protocol of EV charging. Just as SMTP and IMAP let any email client talk to any email server, OCPP lets any compliant charger talk to any compliant platform. You can change the platform without changing the hardware, and you can mix hardware brands behind a single platform.

The protocol is developed and maintained by the Open Charge Alliance (OCA), a non-profit foundation under Dutch law with more than 400 members worldwide, including charger manufacturers, software vendors, network operators, and research organisations. OCA also runs certification testing — an important detail when judging vendor claims.

2. Why open standards matter in EV charging

A charging installation is a long-lived asset. A wallbox installed in a residential building or a fleet depot today is expected to operate for ten years or more. Over that period, the property owner will likely change service providers, add chargers from different manufacturers, integrate new billing systems, and respond to grid rules that did not exist at the time of installation.

Open standards make all of that possible without ripping out hardware. The contrast is sharp:

• Open (OCPP): Hardware and software are decoupled. You can change platform, mix brands, and let multiple integrators compete for your business.
• Proprietary: Hardware only works with the vendor’s own platform. Switching means replacing the chargers, not just the contract.

There is a regulatory dimension too. The EU’s Alternative Fuels Infrastructure Regulation (AFIR), which entered into force on 13 April 2024, requires public charging infrastructure to be interoperable, smart-capable, and to expose real-time data on price, availability, and energy delivered through open APIs. AFIR does not name OCPP, but the data granularity it demands effectively requires OCPP 2.0.1 or later at the charger-to-platform layer.

3. OCPP versions explained: 1.6, 2.0.1, and 2.1

Three OCPP versions are relevant in 2026: 1.6, still dominant in the installed base; 2.0.1, increasingly common on new commercial deployments; and 2.1, released in January 2025 and starting to appear in the field. They differ in transport, security, device model, and what they let an operator do.

A few practical notes. OCPP 1.6 is still the workhorse — most installed wallboxes and commercial chargers use it, and most platforms continue to support it. OCPP 2.0.1 is the version most procurement teams should specify for new installations: it is the first version with serious security profiles and is the baseline most regulators effectively assume. OCPP 2.1 matters today mainly for projects involving vehicle-to-grid (V2G), battery storage, or distributed energy resources.

4. What OCPP enables in practice

Specifying OCPP is not a checkbox exercise. The protocol unlocks specific operational capabilities that directly affect cost, compliance, and user experience.

Load balancing

With OCPP, the platform can set dynamic charging profiles per charger and per session, distributing available capacity across many vehicles. This avoids expensive grid upgrades when several chargers share a fuse. Load balancing is one of the most common reasons property owners replace proprietary systems with OCPP-based ones — see [internal link: /en/solutions/load-balancing] for how this works in a typical BRF or commercial property.

Remote management

Operators can monitor status, restart sessions, push firmware updates, and diagnose faults without a site visit. For a portfolio of hundreds of chargers across multiple properties, this is the difference between a viable operation and a service nightmare.

Smart pricing and tariffs

OCPP carries the metering and session data needed for time-of-use pricing, day/night tariffs, fixed and variable contracts, and roaming. The 2.0.1 transaction model is rich enough to support per-user, per-property, and per-session billing without custom integrations.

Billing and roaming

Because OCPP standardises authorisation and meter values, a charger can be integrated with billing systems, with employer-paid charging, and with roaming networks (typically via OCPI on the platform side). One protocol on the charger; many commercial models on top.

Reporting and compliance

AFIR Article 5 requires real-time availability and pricing data. OCPP 2.0.1 provides the underlying telemetry — connector status, energy delivered, session start/stop — that operators need to expose through their public APIs without bolting on extra data layers.

5. How to tell if a charger is truly OCPP-compatible

“OCPP-compatible” is a phrase used loosely. Some vendors implement the protocol partially, lock it behind their own cloud, or support only a narrow set of messages. Run a charger through this checklist before signing.

• Which OCPP version is implemented? Minimum 1.6J for legacy sites; 2.0.1 for new installations.
• Is the implementation OCA-certified? Ask for the certification reference, not just a marketing claim.
• Can the charger be pointed to any CSMS URL on site, by the property owner or a third-party integrator?
• Are credentials and the CSMS URL changeable in the field — not locked to the manufacturer’s cloud?
• Which OCPP messages and features are supported? Ask for the conformance list (smart charging, firmware update, security profile, etc.).
• What is the security profile? OCPP 2.0.1 defines Security Profiles 1-3; profile 2 or 3 (TLS with certificates) is the practical minimum for public installations.
• Is the charger interoperable with at least two independent CSMS platforms? If the vendor cannot name one besides their own, treat the OCPP claim as marketing.
• Is firmware decoupled from the platform? You should be able to update one without breaking the other.

Does the documentation include the OCPP message log or test reports from interoperability events (Plugfests)?

6. The risks of proprietary systems

Proprietary systems are easy to sell — one vendor, one contract, one app — and they are expensive to leave. The specific risks worth quantifying:

1. Vendor lock-in. Changing platform requires changing hardware. For a 50-charger installation, this can mean a six-figure replacement cost that has nothing to do with the chargers actually being worn out.
2. Pricing power shifts to the vendor. Once a property is locked in, the operator has limited leverage on subscription pricing, transaction fees, and feature charges.
3. Roadmap risk. If the vendor deprioritises a feature you need — or is acquired, or exits the market — you have no fallback.
4. Integration limits. Proprietary systems rarely expose the data needed for property-level energy management, ESG reporting, or AFIR-grade public data.
5. Compliance drift. As regulation evolves (AFIR is being followed by national rules across the EU), a closed system needs the vendor to keep up. An open system lets you change platforms if they do not.

None of this is theoretical. Property owners replacing first-generation proprietary chargers in 2025 and 2026 are doing so largely because the original vendors cannot meet AFIR-grade data and pricing transparency requirements.

7. Choosing OCPP-compatible solutions

A practical procurement approach combines hardware that is genuinely open with a platform that can manage multiple brands.

• On the hardware side: look for OCA-certified chargers with a documented OCPP version, a changeable CSMS URL, and a clear security profile. Most established brands now offer this — Zaptec, Ctek, Alfen, Defa, Charge Amps, Compleo, Garo, and Schneider Electric all ship OCPP-compatible products.
• On the platform side: verify that the CSMS can actually manage chargers from different vendors in production, not only in theory. Ask for references where a single platform manages two or more brands at the same site.

This is the model Waybler builds on. Waybler Connect is a fully OCPP-compatible charging service designed without vendor lock-in. It manages Waybler’s own hardware as well as third-party OCPP chargers from Zaptec, Ctek, Alfen, Defa, Charge Amps, Compleo, Garo, and Schneider Electric. Built in Sweden since 2015 and operating more than 28,000 charging points, Waybler treats open standards as a customer-freedom question rather than a technical detail — see [internal link: /en/products/waybler-connect].