(Elsevier, 2024-07-26) Chiatti, Chiara; Marchini, Francesco; Fabiani, Claudia; Kousis, Ioannis; Carlosena Remírez, Laura; Pisello, Anna Laura; Ingeniería; Ingeniaritza; Institute of Smart Cities - ISC
The pursuit of novel materials for radiative cooling (RC) holds immense promise in addressing building
energy saving and urban overheating. RC capitalizes on the principle of dissipating heat energy into space,
specifically through the atmospheric window between 8-13 μm, to achieve passive cooling of surfaces.
However, the absence of a standardized and reliable methodology for characterizing RC materials has
introduced inconsistencies in research findings, impeding collective advancements in the field. To address this
issue, a dedicated experimental protocol is here introduced, as a unifying benchmark for the characterization
of RC materials. This procedure aims to provide comprehensive, consistent, and precise data regarding crucial
properties of RC cooling materials, including thermal stability, spectral radiative behavior, and thermal
performance under both controlled and realistic boundary conditions. To demonstrate the effectiveness of
our proposed methodology, we designed and implemented a comparative study involving an aluminum-based
and a Vikuiti-based sample incorporating a silica-derived polymer as an emissive layer. Notably, our findings
reveal that the Vikuiti prototype outperforms the aluminum counterpart, primarily attributable to its superior
solar reflectance and thermal emittance characteristics. This research not only advances our understanding of
RC materials but also offers a crucial step toward uniform characterization methods that can catalyze further
research and scaling up of radiative cooling technologies.
