Energy management in homes and buildings is undergoing a fundamental transformation. Buildings are no longer passive consumers of energy, but increasingly act as prosumers, generating, storing, and flexibly consuming energy. This shift affects the entire value chain, from devices and building automation systems to energy management platforms and grid operators. As energy-related assets such as photovoltaic systems, electric vehicle charging infrastructure, and advanced HVAC solutions become more tightly connected, the need for structured, interoperable, and scalable integration becomes critical across all levels. Recent developments within the KNX standard reflect this evolution, addressing these challenges at different levels.
Since the release of KNX specifications version 3.0.4, new Functional Blocks have been introduced to enhance interoperability in the energy management domain. These Functional Blocks provide a standardized approach for complex energy-related applications, enabling more consistent integration across manufacturers and systems.
Key application areas include photovoltaic systems, HVAC, and electric vehicle charging infrastructure, where devices typically expose a high number of data points. By defining common Functional Blocks, KNX reduces ambiguity in interpretation and implementation, allowing systems to interact more predictably and efficiently. This represents an important step towards scalable and interoperable energy management solutions based on KNX.
Alignment with established energy standards
To further strengthen interoperability beyond the building domain, KNX Association is actively collaborating with established initiatives from the energy sector. A key example is the cooperation with the SunSpec Alliance, resulting in a new white paper that decribes the mapping between SunSpec models and the KNX protocol. SunSpec models are widely adopted by major inverter manufacturers and are well known to grid operators. By mapping these models to KNX, this work establishes a clear bridge between building automation and energy systems, facilitating the integration of photovoltaic inverters and related energy assets. This alignment enhances the relevance of KNX in energy management scenarios where interaction with grid-oriented systems is increasingly important.
In parallel, a mapping between SAREF4ENER and KNX, within the context of the Code of Conduct for Energy Smart Appliances (an initiative from the EU commission DG ENER), has been created. SAREF (Smart Applications REFerence ontology) is a standardized vocabulary designed by the European standardization committee ETSI to enable different IoT devices and applications do understand each other. SAREF4ENER is the SAREF part specifically dedicated to the energy domain. This activity, currently work in progress, aims to further align KNX with semantic models used in the energy domain, supporting interoperability at a higher, semantic level.
Vertical integration with energy management systems
Energy management devices and appliances are typically more complex than traditional building automation components. Integrating them exclusively through application-level datapoints can result in increased engineering effort and longer deployment times. On top, the communication is mostly between two devices, i.e. the Home Energy Management System and the energy management device (e.g. the inverter of one’s solar panels in one’s home).
To address this, KNX introduces a form of vertical integration between devices and Energy Management Systems. This approach allows energy-related devices to expose their functionality in a structured and standardized manner toward an Energy Management System, significantly reducing integration complexity and enabling faster roll-outs. At the same time, this does not replace the well-established horizontal integration via ETS. ETS remains the central tool for commissioning and interoperable configuration across KNX devices.
Complementary work going forward
The combination of enhanced Functional Blocks, alignment with energy-sector standards, and selective vertical integration reflects a pragmatic evolution of KNX. It addresses the specific requirements of energy management while preserving the principles of openness, interoperability, and vendor independence that define the KNX ecosystem.
