With regard to climate change, it is imperative to reduce greenhouse gas emissions. One solution approach is to increase energy efficiency in buildings. Buildings contribute a high share of the total global energy usage. As the rate of new building constructions is low, measures applicable to existing buildings become paramount. Before applying new approaches on a large scale, it is necessary to evaluate them in a representative, realistic environment. Living labs such as the Living Lab Energy Campus (LLEC) at Forschungszentrum Jülich (FZJ) facilitate innovative monitoring and control approaches in a real-world setting. In this work, we investigate the required steps for bringing sensor and control networks, comprising more than 1800 devices, into 18 existing and new buildings. This enables both room-level monitoring and control, as well as the integration of building-wide automation. By introducing an ICT infrastructure, we pave the way towards holistic approaches on a district level. We describe the workflows used for selected instrumentation variants and show first insights from the operation of the resulting infrastructure. We show that the investigated instrumentation variants exhibit similar characteristics; however, they affect control behavior differently. We emphasize that instrumentation should be planned in the context of existing infrastructure. Moreover, we present and evaluate sample measurements obtained from different buildings.

Successful adaptation to climate change requires resilient, reliable, and efficient energy systems. To unlock energy efficiency potentials in buildings, an intelligent, user-centered approach is vital. However, this requires handling diverse data on the energy system. Therefore, technologies for harmonizing, storing, and visualizing data, as well as managing physical devices and users are needed. This work assesses existing and required Information and Communication Technologies (ICT) for intelligent building energy system operation. We propose an intermediate architecture based on Internet of Things (IoT) core principles and feature insights from its implementation within the Living Lab Energy Campus (LLEC) at Forschungszentrum Jülich. We present an approach for integrating existing ICT components, such as building energy metering and central Heating, Ventilation and Air Conditioning (HVAC) management, and propose a comprehensive data collection and distribution infrastructure. We establish IoT-enabled applications for energy system monitoring, user engagement, advanced building operation, and device identification and management. We evaluate our ICT setup through functional and performance assessments. We find that heterogeneous data can be reliably collected, distributed, and managed using standardized interfaces, state-of-the-art databases, and cutting-edge software components. For the buildings operated through the ICT infrastructure, data transmission availability is above 98.90 %, mean time to repair (MTTR) is less than 2.68 h, and mean time between failures (MTBF) is in the range of 242.67 h to 1092.00 h, evaluated over a period of three months. Our approach promotes the early real-world adoption of intelligent building control prototypes and their sustainable development. We demonstrate the proposed ICT setup through an experimental study that applies a cloud-based Model Predictive Controller (MPC) to a real building space. Our results provide a comprehensive discussion of the required ICT setup for intelligent building energy system control in real-world environments, and highlight important design strategies that reduce the conceptual overhead and facilitate implementation in similar projects.