Life cycle assessment of energy supply contracted heat supply systems: A case study from Austria

Heat supply systems (HSS) have the particularity that their energy-related services can be outsourced to a third party or contractor, which is usually referred to as energy supply contracting (ESC). Although the economics of ESC have been extensively researched, life cycle assessments of HSS with ESC are rather rare. The aim of this study is to assess the environmental impacts of an HSS operated in Austria, from cradle to grave. The measured energy consumption is used to assess the operational impacts, thus eliminating the need for calculation assumptions regarding efficiency and heat demand. In addition, the trade-off from using more efficient components in HSS, which possibly leads to higher embodied emissions prior to commissioning, is explored. Overall, our results suggest that systems operating with an ESC display better environmental performance, assuming an efficiency difference to conventional HSS of around 16%, even if this leads to higher embodied impacts. To support these conclusions, the next step would be to model these systems in dedicated software. This would also provide a further opportunity to investigate options for further improvements to the systems under consideration.