Enhanced Thermoelectric Cooling Performance through Phase Change Material Integration: Experimental and Numerical Investigation

Water distillation is essential to meet drinking water needs and solar distillation offers a simple, eco-friendly solution for poorer regions lacking resources. This study uses CH3(CH2)16COOH, C31H64, and CH3(CH2)10COOH as PCMs, along with CuO and TiO2 nanoparticles in the solar still coupled with solar water heater. Various models were tested to enhance productivity and performance. The novelty of research introduces an innovative integration of phase change materials (PCMs) and nanoparticles in hybrid solar stills to optimise heat transfer and maximise water yield and exergy performance. The objective of the current work is to enhance the performance of solar desalination by integrating phase change materials (PCMs), nano-additives and preheated feed water. The combined use of paraffin wax, stearic acid, and lauric acid, along with nanoparticles such as CuO and TiO2 with solar-heated feed water significantly improved productivity, thermal efficiency, and exergy performance compared to the baseline setup. The current setup gives better results such as Stearic acid with 25.23% efficiency, Paraffin wax with 40.12% efficiency and Lauric acid with 36.81% efficiency compared to simple solar still. Productivity rose by 25.23%, 40.18%, and 36.61% while using PCMs stearic acid, Paraffin wax, and Lauric acid respectively.

Building envelope systems that integrate Phase Change Materials (PCMs) are solutions aimed at increasing the thermal energy storage potential of the building envelope while keeping its mass reasonably low. Building envelope components with PCMs can be either opaque or transparent and can be based on different types of PCMs and integration methods. In opposition to conventional building components, these elements present thermal and optical properties that are highly non-linear and depend to a great extent on the boundary conditions. Such a characteristic requires the system development and optimisation process during the design phase to be carried out with particular care in order to achieve the desired performance. In this paper, a review of the existing modelling capabilities of different building energy simulation (BES) tools for PCM-based envelope components is reported, and the main challenges associated with the modelling and simulation of these systems through the most popular BES tools (among them, EnergyPlus, IDA-ICE, TRNSYS, IES-VE, and ESP-r) are highlighted. The aim of this paper is to summarise the evidence found in the literature of the latestdevelopment in the successful use of BES to replicate the thermal and optical behaviour of opaque and transparent components integrating PCMs, in order to provide the community of professionals with an overview of the tools available and their limitations.

The residential sector in Egypt is one of the largest energy consumers, exacerbating the energy crisis due to reliance on fossil fuels and the growing gap between supply and demand. This study aims to enhance energy efficiency in the integration of Phase Change Materials (PCMs) into residential buildings for thermal energy storage. The impact of PCM was analyzed using Energy Plus, the simulation engine for Design Builder, focusing on five major Egyptian cities representing different climate conditions. The CondFD algorithm was applied to simulate heat transfer and assess Reinforced building components with PCMs to lower energy use while maintaining in-door thermal comfort. Initially, three potential PCM options are assessed for a baseline residential unit, with M91/Q23 featuring a melting point of 23°C and a thickness of 37 mm was determined to be the most effective configuration when applied to the exterior layers of the building envelope. This PCM is subsequently incorporated into a standard single-story, multi zone residential buildings for further analysis. The average energy savings per month of 17.55% is achieved in Assiut, 16.28% in South Sinai, 16% in Alexandria, 15.68% in Ismailia, and 14.8% in Aswan. It was found that the use of PCMs to improve energy efficiency in residential buildings depends on different types of PCMs and how to select the best type with the best thickness based on their physical properties.

Phase change materials have important application value in the fields of heat storage, cold storage, and thermal shock protection of electronic chips. In particular, in the field of chip thermal shock protection, phase change materials can use the solid-liquid phase change process to absorb a large amount of latent heat, thereby suppressing the temperature rise of the chip and preventing it from overheating. At present, there are mainly three types of common phase change materials: organic, inorganic and metallic phase change materials. There exists significant difference in the thermophysical properties of the three types of materials, and their thermal control performance also have their own characteristics. This paper sorts out the main thermophysical data of the three types of phase change materials. Through theoretical modeling and analysis, the thermal control performance of these materials is quantitatively evaluated and compared. For typical chip thermal shock conditions, the three types of phase change materials are compared, and their typical characteristics are intuitively displayed. The research results can serve as value reference for the development of phase change thermal control technology for chips.

Urban heat stress is an escalating challenge in Sri Lanka, where conventional air conditioning remains the dominant means of thermal relief. Although effective, space cooling systems are energy intensive and environmentally unsustainable. Wearable cooling devices have emerged as a potential alternative, offering localized thermal comfort in outdoor and mobile contexts. Human thermal regulation relies primarily on sweating, which dissipates heat through evaporation. However, sweat distribution is uneven across the body, and in Sri Lanka’s hot, humid climate, where evaporation is often limited, devices that remove heat directly from high-sweat regions present a more effective strategy. This paper introduces a conceptual framework for a hybrid phase change material (PCM) –thermoelectric cooling (TEC) wearable system that optimizes energy usage by integrating the heat storage capacity of PCMs with the active cooling of TECs. Unlike prior studies that employ PCM as heat sinks on the hot side, this work explores PCM integration on the cold side to extend comfort duration while minimizing power demand. The study aims to establish a conceptual foundation for future research into efficient, sustainable, and context-appropriate wearable cooling solutions, particularly for users such as motor-bike riders exposed to high heat and direct sunlight.

Thermal comfort regulation in buildings located in hot climates, such as Indonesia, remains highly dependent on air conditioning (AC) systems, leading to substantial energy consumption. Integrating Phase Change Materials (PCM) into building envelopes offers a passive thermal management strategy to reduce cooling loads. This study investigates the thermal performance of a gypsum-based wall incorporating a eutectic fatty acid PCM (laurate–stearate) of 85:15 (wt%) modified with polylactic acid (PLA) at three PCM:PLA ratios (1:0.6, 1:0.8, and 1:1), alongside a control sample without PCM. Samples were fabricated at laboratory scale and evaluated using a mini-cubicle system under controlled charging and discharging conditions. Energy performance was assessed through temperature change rates and heat transfer (q) analysis at three measurement points (T1, T2, T3). Results demonstrate that PLA modification significantly enhances PCM performance, with the 1:0.8 ratio (bPCM) exhibiting optimal behavior. During charging, bPCM achieved the lowest temperature change rates of 4.75 °C/h at T1, 1.15 °C/h at T2, and 0.65 °C/h at T3 and the minimum heat transfer from T2 to T3 of 32.049 J. Similarly, during discharging, bPCM maintained the smallest temperature change rates of 2.2 °C/h at T1, 1.0 °C/h at T2, and 0.65 °C/h at T3 with the lowest heat transfer to the indoor zone of 32.033 J. These findings confirm that optimized PLA-modified eutectic PCM significantly improves heat absorption, latent heat storage, and thermal insulation performance compared to non-PCM and non-optimized compositions. The proposed composite wall system demonstrates strong potential for passive cooling enhancement and building energy efficiency improvement in hot-climate regions

Thermal modelling of a flat plate solar collector with latent heat storage validated with experimental data in outdoor conditions

Optimization of tube arrangement and phase change material for enhanced performance of solar air heater- A numerical analysis

A ventilated cooling ceiling with integrated latent heat storage—Monitoring results

Thermal energy storage (TES) platforms can help to improve the energy efficiency of various types of thermal management systems by actively modulating the transient response of these integrated thermal systems. A novel strategy for TES platforms involve the integration of Phase Change Materials (PCM) into various types of heat exchangers (HX). High performance, compact, and low cost HX platforms for TES involving PCM are often desired for applications such as power plants, edifice thermal management, transportation technologies (e.g., aerospace and automotive vehicles), and high heat flux electronics cooling. These applications are often constrained by requirements for minimizing pressure loss, miniaturizing the form factors, and the need for easy scalability to large systems. This imposes steep challenges for design, fabrication, and operation of these HX platforms. This also severely restricts the available options and material choices for PCM. In this experimental study, the transient performance of a Plate Heat Exchanger (PHX) integrated with PCM were analyzed for realizing a Latent Heat Storage Unit (LHSU). This study enabled a detailed experimental characterization of the efficacy of the LHSU realized in a PHX (model: SWEP B5T). The inner volume of the PHX was filled up with PCM. The PCM considered was PureTemp 29 with a phase transition temperature of 29 °C. The temperature of the Heat Transfer Fluid (HTF) was varied from 32°C - 38°C for melting and 20°C - 26°C for solidification. The HTF used in this study was water. The volumetric flow-rate ranged from 5, 7.5 and 10 GPH. Experimental validation for the transient response of the LHSU (i.e. the charging and discharging time periods) were performed by parametrically varying the design and operational conditions, which include: flow rate, fluid inlet and exit temperatures, and the energy storage capacity.

Thermal energy storage systems are crucial for reducing dependency on fossil fuels and minimizing CO2 emissions. The building sector is a major sector responsible for producing high levels of CO2 in most countries (including Qatar). Thermal energy storage can be accomplished either by using sensible heat storage or latent heat storage components. Latent heat storage is more attractive than sensible heat storage because of its high storage density with smaller temperature fluctuations.[1] The materials able to utilize latent heat which can undergo phase changes (usually solid to liquid changes) at relatively low temperatures, while absorbing or releasing high amounts of energy are called phase change materials (PCMs).[2] Most promising PCMs are paraffin waxes which contain saturated hydrocarbon mixtures. They are frequently used due to their numerous advantages such as high latent heat of fusion, negligible super-cooling, and chemical inertness.[3,4] In this contribution, thermal properties of the PCMs based on linear low density polyethylene (LLDPE), different types of paraffin waxes with melting points, 25 oC and 42 oC, and expanded graphite (EG) were characterized by unique transient guarded hot plate technique (TGHPT), which allow to identified thermal properties of large sized samples[5] in comparison with commonly used ifferential scanning calorimetry (DSC). It was confirmed that all prepared PCMs were able to store and release huge amount of thermal energy. The 25 % increase of capacity to store and release a thermal energy was observed by PCMs contains paraffin wax with melting point 25 oC in comparison with paraffin wax with melting point 42 oC. Also reproducibility of storage and release heat of the PCMs by repeating of heating and cooling process has been demonstrated. Moreover, the increase of the EG content in the PCMs led to the increase of thermal conductivity from 0.24 W/mK for PCMs without EG to 1.3 W/mK for PCMs contain 15 wt.% of EG. Additionally, life cycle assessment of prepared PCMs has been demonstrated to identify the effects of these new materials on the Qatar environment. Our results indicate that using of PCMs in building industry can reduce emission of CO2 up to 10%.

Thermal and optical characterisation of dynamic shading systems with PCMs through laboratory experimental measurements

Limestone calcined clay cement (LC3) has emerged as a promising low-carbon alternative to ordinary Portland cement (OPC) due to its reduced clinker content and associated carbon footprint. In parallel, integrating phase change materials (PCMs) into cementitious composites offers a pathway to enhance building thermal regulation through latent heat storage. However, hydrophobic PCMs may adversely affect fresh workability and hardened performance, particularly by promoting entrapped air and increasing porosity. This study investigates the incorporation of capric acid (CA) as an organic PCMs through partial cement replacement (0%, 1%, 5%, and 10% by mass) in OPC and LC3 mortars. In this context, the mortar is a functional organic–inorganic composite, where the organic PCMs phase contributes thermal energy storage functionality. Unlike most PCMs studies focused on OPC systems, this work emphasises LC3 and identifies air-void control as a critical mechanism for performance recovery in LC3–PCMs composites. It also evaluates the effectiveness of a silicone-based defoamer (0.15% by mass of the total mixture) in mitigating air-related performance losses. Fresh flowability, hardened density, ultrasonic pulse velocity, and compressive strength were determined up to 28 days. Results showed that increasing CA content reduced flowability, density, UPV, and compressive strength in both OPC and LC3 systems, indicating that hydrophobic PCMs inclusion adversely affected matrix continuity. However, the incorporation of a silicone-based defoamer enabled performance recovery in both OPC and LC3 composites by improving matrix compactness through air-void control. Overall, the results demonstrate that air-void control is critical for PCMs-modified mortars, and that defoamer addition provides a practical approach to improve the performance of LC3–PCMs systems while maintaining their sustainability benefits.

Spectral optical performance of phase-change-material-filled glass-block system: Experimental evaluation and comparative exploration

Design of an H2O-LiBr absorption system using PCMs and powered by automotive exhaust gas