Abstract :
[en] In a context of growing pressure to reduce the building stock carbon footprint, newly designed buildings tend towards zero-emission standards. Yet improving existing ones often requires additional insulation and deep revamping which, most of the time, present payback times above 30 years. On the other hand, switching from liquid or gaseous fossil fuels (typically natural gas or fuel oil) to electrified sources (e.g., heat pumps) is also very costly and partly resolves the issue by displacing the fossil fuel use from heating/cooling towards electricity production. Thermal networks are more and more fostered by new policies as they offer the economy of scales and peak demand shaving in order to decrease the costs and enable a profitable decarbonised energy supply. This work aims to provide a tool that assesses the impact of energy saving measures at the building level (such as insulation or temperature set point adjustment) coupled with the operation and design of thermal networks (e.g., high or low-temperature networks, advanced control strategies, thermal storage…). Most of the existing tools consider separately the network operation and the building comfort conditions transforming the decision-making process into a lengthy trial and error process. To accelerate the decision process, a physical dynamic-modelling of the thermal network is coupled to the building structures which predicts the perceived indoor temperature based on the operation of the thermal network, ambient conditions and building use. The detailed dynamic building models enable a precise estimation of load demand curves, thus providing a direct link between indoor temperatures and energy consumption. To underline the effectiveness of the approach, the models, developed on the Dymola modelling platform, are applied to the case study of Liège Airport who is committed to decarbonize their activities linked to the building stock operation (offices, fret halls, passenger halls,…) yet face the aforementioned challenges. This research is focused on showing the capability of a low-temperature thermal network to best meet the heating demands while minimizing the environmental impact. Several decarbonisation strategies are proposed showing how thermal networks can help this purpose.
