Preliminary environmental benchmarks for a new Photonic Meta-Concrete based on state of the art radiative cooling materials

Abstract

The usage of conventional air-conditioners increased due to global warming and the urban heat-island-effect in cities. These systems are responsible for 7% of global greenhouse gas emissions and 10% of the total energy consumption. Radiative Cooling is a passive cooling strategy which tries to mitigate global warming and the urban heat-island-effect by emitting heat through the atmosphere, into outer space. These materials are already studied for several decades, but for the first time a radiative cooling material is under development based on conventional concrete. In order to evaluate the environmental performance of this newly developed material compared to existing cooling materials, environmental benchmarks need to be defined. To determine such benchmark, existing, state of the art, daytime radiative cooling materials are assessed in this paper. Information on these materials is collected through a literature review. The radiative cooling materials are modelled using the generic Ecoinvent v3.6 database and the environmental impact is assessed using the Belgian LCA method for buildings, i.e. the MMG method. This method is in line with the EN15804:A2 and covers 16 environmental impact categories, such as global warming potential, acidification, eutrophication, water scarcity and toxicity. The results show that the production process of the materials, i.e. thin film deposition techniques, are poorly represented in the Ecoinvent database. Assumptions and adaptations are made based on literature and experts’ feedback. A sensitivity analysis is carried out to gain insight in the uncertainty of the assumptions made. Based on the results, preliminary environmental benchmarks are generated and the environmental impact of the first composition of the photonic meta-concrete is assessed against these benchmarks.