Enhancing building wall thermal performance with phase change material and insulation: A comparative and synergistic assessment

TUNÇBİLEK E., ARICI M., Krajčík M., Li D., Nižetić S., Papadopoulos A. M.

Renewable Energy, vol.218, 2023 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 218
  • Publication Date: 2023
  • Doi Number: 10.1016/j.renene.2023.119270
  • Journal Name: Renewable Energy
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Aquatic Science & Fisheries Abstracts (ASFA), CAB Abstracts, Communication Abstracts, Compendex, Environment Index, Geobase, Greenfile, Index Islamicus, INSPEC, Pollution Abstracts, Public Affairs Index, Veterinary Science Database, DIALNET, Civil Engineering Abstracts
  • Keywords: Buildings, Energy saving, Latent heat activation, Phase change material, Thermal insulation
  • Kocaeli University Affiliated: Yes


The energy-saving effect of phase change materials (PCMs) and conventional thermal insulations has traditionally been considered separately, although a purposeful combination of the two could increase energy-savings. Therefore, this study investigated the energy benefits of PCM and conventional thermal insulation applied separately or in combination in a building external wall. A numerical model was developed and validated with analytical solution and experimental data. In the comparative analysis, PCM located on the interior side of the wall outperformed insulation for layer thicknesses ≤ LPCM = 16 mm. In the best case, PCM saved 38.2% more energy than insulation at a layer thickness of LINS = 6 mm. A parameter (ψ) defining the ratio of LPCM to LPCM + LINS was introduced. The synergistic effect evaluation revealed that using a composite of PCM and insulation (C5 configuration, ψ = 0.05) conserved up to 7.3% of energy compared to only insulation application (ψ = 0). Besides, configuration C6 with ψ = 0.15 provided 6.4% more energy saving than ψ = 0. Furthermore, the combined designs with 0 < ψ ≤ 0.6 outperformed ψ = 0 for C5, C6, and C10 configurations. Overall, a marginal positive effect on the energy saving was observed for the combined design compared to insulation only. Latent heat activation was critical for obtaining improved thermal performance.