Influence of technical and electrical equipment in life cycle assessments of buildings: case of a laboratory and research building

Abstract

Purpose: A detailed assessment of the environmental impacts of the building requires a substantial amount of data that is time- and effort-consuming. However, limitation of the system boundary to certain materials and components can provide misleading impact calculation. In order to calculate the error gap between detailed and simplified assessments, the purpose of this article is to present a detailed calculation of the environmental impacts of the building by including in the system boundary, the technical, and electrical equipment. Method: To that end, the environmental impacts of a laboratory and research building situated in Graz-Austria are assessed following the EN-15978 norm. Within the system boundaries of the study, the material and components of building fabric, technical, and electronic equipment for the building lifecycle stages of production, construction, replacement, operational energy and water, and end-of-life are considered. The input data regarding the quantity of materials is collected from the design and tendering documents, invoices, and from discussion with the head of the building’s construction site. Primary energy and global warming potential indicators are calculated on the basis of a functional unit of 1 m2 of energy reference area (ERA) per year, considering a reference building service life of 50 years. Results and discussion: The primary energy indicator of the building is equal to 1698 MJ/m2ERA/year. The embodied impacts are found to be responsible for 28% of which 6.4% is due to technical and electronic equipment. Furthermore, the embodied impacts for the global warming potential, equal to 28.3 kg CO2e/m2ERA/year, are responsible for 73%. Together, technical and electrical equipment are the largest responsible aspects, accounting for 38% of the total impacts. Simplified and detailed result comparisons show a gap of 29% and 7.7% for global warming and primary energy indicators. These differences were from the embodied impacts and largely from the exclusion of electrical equipment from the study’s system boundary. Conclusions: Technical and electrical equipment present a significant contribution to the overall environmental impacts of the building. Worthy of inclusion in the system boundary of the study, the environmental impacts of technical and electrical equipment must be calculated in detail or considered with a reliable ratio in the early design phase of the project. Further research is necessary to address the detailed impact calculation of the equipment and notably the minimization of their impacts.