The rules of the smart charging game are changing – and quickly. ISO 15118 and OCPP 2.0.1 have moved from being goals to essential requirements. They now sit alongside strict measures like the UK’s Public Charge Point Regulations 2023 and Smart Charge Points Regulations 2021. For anyone designing charging infrastructure, whether it’s domestic wall boxes or 350kW rapid chargers, “compliant” means something very different from a couple of years ago.

UK charging standards are evolving faster than most automotive electronics cycles can keep up with. With multiple regulations and quickly changing protocol versions, manufacturers face a compliance landscape more complicated than any previous generation of charging hardware. The risks of falling behind are significant. Wasted R&D investment, products that can’t reach the market, costly retrofit programs and reduced market access are all issues as charge point operators and fleet managers make compliance a key factor in purchasing decisions.

The emerging standards are not just changing certification checklists. They are deciding which products make it to market and which get stalled in development or fail in the field.

The convergence of standards and regulations

The UK market has become a testing ground for the latest EV charging standards. A shifting mix of technical and regulatory requirements is increasingly shaping product development cycles. Central to this is ISO 15118, which significantly changes vehicle-to-charger communication through secure cryptographic handshakes, certificate-based authentication and two-way data exchange.

At the same time, the Open Charge Point Protocol, long dominated by version 1.6, is seeing increased industry uptake of version 2.0.1, with the newer OCPP 2.1 specification now published as the latest release, bolstering distributed energy resource control and improving vehicle-to-grid support. This change means charge point controllers need to act as advanced grid edge devices instead of just basic power delivery tools.

The existing regulatory framework also plays a crucial role. Since June 2022, the Smart Charge Points Regulations have required all new domestic and workplace chargers to include default off-peak scheduling, random start-up delays of up to 30 minutes, and strong cybersecurity measures.

ISO 15118: beyond simple communication

From an automotive electronics viewpoint, implementing ISO 15118 poses one of the biggest technical challenges in modern charging infrastructure development. The protocol enables “Plug & Charge” functionality, which allows for automatic authentication and payment authorisation without user intervention. However, meeting the technical requirements is demanding. At the physical layer, ISO 15118 requires powerline communication capability. This is usually achieved through dedicated powerline communication (PLC) modem chipsets like the Qualcomm QCA7005 or Lumissil CG5317.

Those components bring with them new Electromagnetic Compatibility (EMC) considerations and power management issues. The PLC modem needs to maintain reliable communication across different power quality conditions, electrical noise environments and cable lengths, all while working alongside high-power switching electronics.

The cryptographic requirements are just as strict. ISO 15118 requires TLS 1.3 for secure communication channels. It uses X.509 certificate-based authentication managed via public key infrastructure systems. For charge point manufacturers, this means integrating either secure elements or hardware security modules that can perform elliptic curve cryptography operations without overloading the main processor. Managing the certificate lifecycle, which includes secure storage, regular renewal and revocation checking, is crucial since failures could make functional chargers inoperable.

The protocol’s state machine implementation needs careful firmware design. ISO 15118 outlines several charging modes, ranging from basic energy transfer to advanced grid services and bidirectional power flow. A solid implementation must manage transitions between these states smoothly, with effective error handling and seamless fallback mechanisms to the older IEC 61851 charging modes.

OCPP evolution and backend integration

The shift to OCPP 2.1 brings a new set of challenges, mainly focused on the charge point’s role as a grid edge intelligence platform. The controller now needs to act as an advanced power management system: It must respond to grid signals, manage energy storage systems and work with building management infrastructure.

Many manufacturers are using dual-stack approaches with feature flags, allowing them to enable advanced capabilities selectively without completely redesigning the hardware. This modular approach to the firmware architecture enables the same hardware platform to serve legacy charge point operators, but also prepare products for future network needs.

Communication requirements are changing, too. Charge point controllers must handle larger message queues, use complex retry logic and keep local transaction records, even during long network outages. For systems in cellular-connected setups or places with unreliable Internet access, these buffering and retry methods are crucial for staying within regulatory standards.

Hardware design implications

The evolving requirements across the electronic and automotive sectors all have significant effects on charge point hardware design. Processing needs have risen sharply, and modern designs typically use ARM Cortex-A processors with at least 512 megabytes of RAM, providing enough computing power for TLS operations, protocol management and user interface tasks.

At the same time, security hardware needs have also tightened, necessitating dedicated secure elements or trusted platform modules. Both offer tamper-proof storage for cryptographic keys and certificates, which should be integrated early in the design process as they influence board layout, power management and firmware start-up systems.

Power supply design has become more complicated, too, as modern charge points must handle the main power electronics at the same time as supporting always-on communication systems, PLC modems, display interfaces, payment terminals and connectivity hardware.

Balancing power use in standby modes whilst keeping communication ready poses significant efficiency challenges. EMC compliance is more difficult as charge point electronics become more intricate. High-power switching electronics, RF communication systems, PLC modems and sensitive cryptographic processors increase the chances of electromagnetic interference. Careful PCB layout, shielding methods and filter design are essential for achieving CE and UKCA certification.

Firmware architecture for future-proofing

Modular software architecture has become vital to future-proofing firmware design, since it cleanly separates hardware abstraction layers, communication protocol stacks and application logic. This separation allows for protocol updates without affecting safety-critical power control code, lowering certification costs.

Over-the-air update capability is vital for maintaining security and meeting regulations throughout multi-year deployments. Production-grade OTA systems require atomic update processes with automatic rollback on failure, signed firmware images with cryptographic checks and staged deployment options.

Security hardening goes beyond cryptographic methods and covers the entire firmware environment. Secure boot processes, memory protection measures and monitoring for unusual activity all strengthen security for connected infrastructure.

Testing and validation complexity

Interoperability testing has become one of the most time-consuming parts of charge point validation. Challenges include vehicle manufacturers implementing ISO 15118 with different levels of detail and timing that only emerge during extended testing. While gaining access to a sufficiently broad vehicle test fleet also requires significant investment, and load testing is needed in parallel to verify system performance under peak and degraded operating conditions.

Security penetration testing has become important as independent researchers find vulnerabilities in deployed charging infrastructure. This includes network-accessible interfaces, physical security issues and potential side-channel information leaks.

Field trials in realistic deployment settings confirm what lab testing cannot. Real-world electrical conditions, extreme environments and long operation periods stress systems differently, speeding up wear and exposing design flaws.

In 2026, and beyond

Looking ahead, several considerations stand out. Early adoption of advanced features can offer manufacturers competitive procurement advantages, but it also carries the risk of committing to specifications that may still change. To counter this, a modular architecture that allows selective feature activation offers a balanced approach, giving manufacturers the freedom to ship hardware with hidden capabilities that can be activated later through firmware updates, when standards settle.

Engaging with standards bodies, especially CharIN for ISO 15118 and the Open Charge Alliance for OCPP, gives insights into upcoming changes before they become requirements. Being active in engagement and participation affords savvy companies the opportunity to influence how standards evolve and prepare for them sooner than competitors might.

The charging infrastructure market is moving towards platform strategies where hardware supports software-defined functions. So, investing in strong hardware platforms with extra computing capacity and modular firmware architectures that allow rapid feature development will be the road to success.

EV charging standards will continue to change, with more advanced vehicle-grid integrations, improved security needs, and a greater focus on interoperability all key to success. Automotive electronics engineers must balance delivering products that meet current needs but are flexible for future standards, and those who do will stay ahead of the game.

A final thought from me is to recommend investing in flexible hardware and firmware platforms instead of quick fixes, and to remain ever-agile as the industry rapidly shifts toward a fully electric transportation future.

Dunstan Power, Managing Director, smart charging consultancy, Versinetic