PCM Cement-Lime Mortars for Enhanced Energy Efficiency of Multilayered Building Enclosures under Different Climatic Conditions

Abstract

Phase change materials (PCMs) are promising materials for the energy efficiency improvement of building enclosures, due to their energy storage capacity. The thermal behaviour of a multi-layered building enclosure with five different compositions of PCM cement-lime mortars was evaluated under heating and cooling cycles. The behaviour of cement-lime mortars with 20% of microencapsulated PCM mixed with other additions, such as cellulose fibres and perlite, a lightweight aggregate (LWA), were studied under climate conditions of 15 °C–82% RH (cooling) and 30 °C–33% RH (heating) that were applied with a climatic chamber. Temperature and heat flux on both sides of the multi-layered enclosure were experimentally measured in laboratory tests. Temperature was also measured on both sides of the PCM cement-lime mortar layer. It was observed that the addition of the PCM cement-lime mortar layer delayed the heat flux through the enclosure. During a heating cycle, the incorporation of PCM delayed the arrival of the heat wave front by 30 min (8.1% compared to the reference mortar without PCM). The delay of the arrival of the heat wave front during the cooling cycle after adding PCM, compared to the reference mixture, reached 40.6% (130 min of delay). Furthermore, the incorporation of LWA in PCM cement-lime mortars also improved thermal insulation, further increasing energy efficiency of the building enclosure, and can be used not only for new buildings but also for energy rehabilitation of existing building enclosures.

Combined Effect of Superabsorbent Polymers and Cellulose Fibers on Functional Performance of Plasters

“…As is visible, the thermal conductivity was dropped in line with the decreased porosity from the initial 0.55 W/(mK) to 0.43 W/(mK). The utilization of both admixtures resulted in a relatively small improvement; however, according to similar research performed by Gueardia et al [42] and Lee et al [43], only minor changes were expected. In particular, the increased water absorption capability of SAP diminished the beneficial effect of increased open porosity on thermal resistance due to the formation of highly conductive hydrogels having higher thermal conductivity.…”

Energy in Construction and Building Materials

“…Most of the research studies covered the topic of thermal energy storage (TES) in construction and building components: i.e., in wooden façade [ 11 ], optimum placement of heating tubes [ 12 ], use of iron (III) oxide powders for modifying the mortar thermal conductivity and diffusivity [ 13 ], fiber-reinforced geopolymers for sensible TES [ 14 ], thermal insulation waste extruded polystyrene [ 15 ], highly insulated wall systems with exterior insulation of polyisocyanurate [ 16 ], thermal properties of high-strength concrete containing CBA fine aggregates [ 17 ], heat conductivity properties of hemp-lime composites [ 18 ], insulating glass units subjected to climatic loads [ 19 ], conduction mechanisms in graphene nanoplatelets (GNPs)-cement composite [ 20 ], and bio-waste thermal insulation panels [ 21 ]. The remaining articles directly disseminated research on storing solar and/or environmental latent heat to level-out daily temperature differences through the smart use of Phase Change Material (PCM) [ 22 , 23 , 24 , 25 ]. They provided experimental and numerical studies on advanced PCM (latent) composites, consisting of porous cementitious materials, which have the potential to store/release large latent TES energy during phase changes, i.e., from solid to liquid and vice versa.…”