Use of the digital twin using the example of the LUX pavilion at Mainz University of Applied Sciences

The LUX Pavilion is an exchange and presentation platform of Mainz University of Applied Sciences for students, lecturers and external partners from business, culture and research that enlivens Mainz city center.

In addition to its function as an event venue, the LUX Pavilion serves as a pilot project for a complete digital twin of a building. One of the aims is to show how building automation (BA) can be linked with building information modeling (BIM) in order to optimize energy efficiency, operational management and maintenance.

As part of a real-world laboratory led by Prof. Thomas Giel and lecturer Christian Wild, a continuous data flow from the building automation system (BA) to the BIM model and the integration of all building data and building automation functions in a central, digital platform is to be implemented. This includes the digital recording and visualization of the physical building elements including the technical building equipment (TBE), i.e. including, for example, the heating, ventilation and air conditioning systems and the resulting building automation functions. The approach to be tested in the real laboratory thus enables the live data transfer of the building functions into the BIM model.

Overview: from BACS to BIM

The path taken to integrate building automation into the BIM model promises

• live data transfer from the building automation system (BACS) to the BIM model.
• high efficiency gains for all project participants.
• a solution for existing and new buildings.
• the use of standard interfaces at all process levels.
• machine support to simplify and accelerate data capture and processing.
• consideration of IT security and data protection requirements.
• the creation of a “living” digital twin that is continuously updated.
   

Mapping the envelope and technical building equipment

The digital recording and visualization of physical building elements (e.g. façade, walls, doors, roof, etc.) and the integration of technical building equipment (e.g. heating, ventilation and air conditioning systems) are the basis for modeling, analyzing and optimizing the function of the technical systems.

Mapping of building automation functions

The digital modelling of all building functions (e.g. air conditioning, lighting, shading) and the live data transfer from the building automation system to the BIM model enable the optimization of energy consumption and operating processes using both traditional methods of system modelling and data-based analyses with the help of artificial intelligence.

Technical integration and data processing

The building functions and energy consumption are recorded via existing bus interfaces such as BACnet, M-Bus, ModBus, LoRa or similar and summarized in a central data point list. A key objective is then to standardize and homogenize the data addressing in order to make the data universally interpretable. This is particularly important for existing buildings, which generally have very heterogeneous system and data landscapes.

The BACtwin user addressing system is used here, which the AMEV working group for mechanical and electrical engineering in state and municipal administrations published as a recommendation in 2024. The standardization is technologically supported by the application of the research results of Dr. Maximilian Both (Entendix GmbH), who wrote his doctoral thesis on this task.

The next step is to transfer the data, which can now be interpreted across systems, into an internationally standardized building and facility management ontology. The Brick and RealEstateCore ontologies are suitable for this due to their broad acceptance.

By mapping the ontologies with the BIM model via the digital twins of the CAD tools, the GA systems are available with their functions and, for example, their energy consumption in the BIM model, which then acts as an SSOT (Single Source of Truth - summary of all data in one central location) for all operationally relevant data.

ESG reporting and sustainability

Environmental Social Governance (ESG) is existential for almost all medium-sized and large companies in the EU due to the EU's “Green Deal”. Building data is required for ESG reporting because it demands continuous improvement, for example in CO2 reduction, which must be achieved and proven. Simulation and forecasting are prerequisites for the continuous improvement of CO2 reductions. This is where the digital twin of the building and its BA functions come into play.

Shortage of skilled workers and AI

The baby boomer retirement wave and the ever-increasing shortage of skilled workers are making the efficient operation of technical building equipment (TBE) increasingly challenging.  The standardization and interpretability of the data achieved through the procedure enables the use of both model-based optimization methods and artificial intelligence (AI) in building operation. Classic type errors are detected immediately and forecast-based optimizations are made possible. This approach alone promises energy savings of 20-30% in existing buildings.

In addition, with the support of augmented reality and AI-based knowledge management, for example, even less qualified people can carry out work on site under supervision. The digital twin of the building forms the basis for the application.

Maintenance and servicing

The malfunction or failure of heating, cooling, ventilation and hot water supply systems causes high costs in building operation. The digital twin provides information about the installed components, their function and maintenance status. The targeted replacement of components and predictive maintenance further reduce costs, cut energy consumption and deploy human resources more effectively.

Internet of Things (IoT) and smart buildings

Buildings are becoming more complex and more and more sensors are being installed. The management of sensors and the data they collect is becoming increasingly important for the smooth and safe operation of buildings. The digital twin enables monitoring and provides information on the make, condition and installation location as well as any necessary safety-relevant software updates.

Overview: Use cases

The use of the digital twin provides support in many areas:

• Information on the ESG CO2 footprint
• Technical operations management
• Maintenance tenders such as number of filters, types of ventilation systems, spare parts, light sources ...
• Retrieval of localization and information on the assets,
• Efficient execution of activities by specialist personnel and use of materials
• Building data of the BIM model is stored in a Common Data Environment (CDE) as SSOT, data is and remains the responsibility of the operator
• Warranty management
• Legal certainty
• Information on dismantling

Legal background GEG

An important legal requirement for building automation can be found in the Building Energy Act (GEG). From 01.01.2025, §71a stipulates building automation and control systems and monitoring in all existing and new non-residential buildings with a total rated output of 290 kilowatts or more for heating and air conditioning.

To meet the requirements, a non-residential building must be equipped with digital energy monitoring technology.

Hurdles and solutions

Scan2BIM

(Scan to Building Information Modeling) is a process in which real building structures are digitally recorded using 3D laser scanning or photogrammetric techniques in order to create precise 3D models. This allows the physical components of existing buildings to be captured and digitized quickly and cost-effectively

Low coding

Ready-made configurations help to set up the system quickly. A low-code environment with a graphical user interface is very user-friendly for efficiently completing digitization tasks

AI support

Data analysis and mapping should be automated as far as possible. This can relieve the burden on personnel capacities and resources can be used more efficiently. Improve the quality of data mapping. Training AI with plans and rule schemas.

Summary

The LUX Pavilion illustrates the potential of a digital twin for optimizing building operations and as a basis for future sustainable smart building concepts. The integration of BA and BIM improves efficiency, reduces costs and contributes to achieving regulatory sustainability targets.

A digital twin enables precise analysis and optimization of technical systems as well as data-based predictions for operational management. The benefits are

• Automated data flow: increased efficiency through the integration of existing and new building data.
• Lifecycle-oriented building operation: long-term optimization of maintenance and operating costs.
• IT security and data protection: consideration of current security requirements.