Master's Thesis by Laura Stiehl

Background: In light of the energy transition, rising energy costs, and the resulting stricter regulations under the Energy Conservation Ordinance, the topic of “energy-efficient construction” is playing an increasingly important role in German construction companies. This master’s thesis, conducted in collaboration with the construction company Karl Gemünden GmbH & Co. KG as a practical partner, aims to enable a direct comparison of the energy efficiency of different design approaches. The objective of this master’s thesis was to answer the following questions:

• How does the building services equipment used influence the annual primary energy demand of new hotel buildings, and what savings potential does this result in?
• Is a detailed thermal bridge calculation preferable to a simplified thermal bridge assessment?
• Is concrete core activation a recommended alternative to conventional cooling systems for hotel operations?
• What factors have a decisive influence on the summer thermal protection of non-residential buildings?

Method:

• Creation of a 3D building model as the basis for computer-aided heat demand calculation
• Application of the following legal standards: Energy Saving Ordinance 2014, DIN V 18599, DIN 4108-2, DIN 4108-6, DIN 4108-4
• Computer-aided determination of the Psi value using the ZUB ARGOS Pro 2014 software
• Conducting a simulation of summer thermal protection using the ETU-Planer software

Result: How does the building services equipment used affect the annual primary energy demand of new hotel buildings, and what savings potential does this result in? The computer-aided heat demand calculation in accordance with DIN V 18599 for non-residential buildings in the case study “New Construction of the Saalwächter Hotel with Commercial Building” yielded the results shown here. Is the precise thermal bridge calculation preferable to the flat-rate method? A comparison of the simplified thermal bridge assessment with the precise thermal bridge calculation shows that the effort required for the precise calculation is only minimally higher than that for the simplified assessment, and that the thermal bridge surcharges can be reduced compared to the simplified assessment. The resulting energy-saving potential thus justifies the increased effort required during the planning phase of a construction project to account for thermal bridges precisely. Is concrete core activation a recommended alternative to conventional cooling systems for hotel operations? Concrete core activation represents an innovative alternative to conventional cooling systems. However, at its current stage of development, concrete core activation is not suitable for use as the sole cooling system in a new hotel building and is therefore not recommended, as it is a very slow-responding system with low capacity limits that does not allow for individual room control or the use of suspended ceilings or raised floor systems, and thus cannot meet the operational requirements of a hotel. What factors have a decisive influence on the summer thermal protection of non-residential buildings? The dynamic thermal building simulation of the case study shows that summer heat protection is significantly influenced by the type, orientation, color, and rear ventilation of the sunshade system.