Ontology-Driven Semantic Interoperability for Smart Communities: Integrating Distributed Energy Data for Digital Twins

The transition toward decentralized and data
intensive energy systems calls for interoperable mechanisms to
integrate heterogeneous data generated by distributed assets, sen
sors, and digital services across smart communities. This paper
presents an ontology-driven semantic interoperability framework
that harmonizes diverse energy data streams into a unified
knowledge graph under a common data model. The proposed
architecture combines a semantic broker, standard ontologies
based on Smart Applications Reference (SAREF) ontology, and
graph-based storage to support consistent, machine-interpretable
representations of energy assets and measurements, while en
abling flexible querying through semantic and graph-oriented
interfaces. The framework is validated with real-world data
from a digital twin (DT)-enabled residential IoT microgrid living
lab in Aalborg, Denmark, using a wind turbine dataset that
captures the turbine status and its active power values. The
results demonstrate, through a proof-of-concept validation, that
the proposed framework can semantically integrate the consid
ered energy data into a coherent, queryable knowledge graph,
constituting an initial step toward an AI-ready foundation for
community-scale DTs, cross-domain analytics, and data-driven