Energy-efficient buildings generally have extensive technical infrastructure involving a range of complex functions and interactions. Ever increasing demands are placed on the performance and functionality of these systems. Simulations can be used to optimise planning across all trades. Building automation systems are then used to implement the corresponding services.

Various energy-efficient buildings were evaluated in the Energy- Optimised Construction (EnOB) research initiative organised by the German Federal Ministry of Economics and Technology. One finding was that actual measured building performance is frequently worse than the theoretical calculated values. In practice, the efficiency potential of these buildings is not being exploited. Reasons range from simple operator errors to complex hydraulic problems. Excessively long operation times and simultaneous heating and cooling in one system or in the same room are typical examples. A key problem seems to be the lack of efficient tools for defining and monitoring the building’s systems. Planning tools available at the present time focus exclusively on the planning phase. They do not contain interfaces for monitoring and analysis once the building is in operation.

As this overall consideration of the design, implementation and operation of a building has been lacking, inefficient operating processes, faults and errors often go undiscovered for some time. As part of a research project supported by the German Federal Ministry of Economics and Technology, the Institute of Building Services and Energy Design (IGS) at Technische Universität Braunschweig in partnership with software engineers from RWTH Aachen University have realised the vision of a technological platform that for the first time allows automatic linking between the planning and operation of building services. Called Energy Navigator, it is a tool for energy-efficient building management that enables this essential integrated view over a building’s life-cycle.