Numerical Evaluation of PCM-Enhanced Concrete Block Walls for Energy Savings in Palestinian Residential Buildings

Description

Heating and cooling homes requires a lot of energy to keep indoor temperatures comfortable. In Palestine, improving the thermal performance of building walls could help reduce this energy use and the cost of electricity. One possible way is to add phase change materials (PCMs) to concrete block walls. These materials absorb heat when they melt and release it when they solidify, allowing the wall to store heat and release it later. This project will investigate whether adding PCM to the walls of a residential building in Nablus can reduce the energy needed for heating and cooling. We will test different melting temperatures, PCM thicknesses, and positions within the wall. The materials under consideration include paraffin waxes such as RT22HC and RT25HC, salt hydrates such as calcium chloride hexahydrate, and bio-based materials such as fatty acids and coconut oil derivatives. Material properties will be taken from previous studies and manufacturer data. The work will be carried out using ANSYS and EnergyPlus. ANSYS will be used to study heat transfer through the walls and the melting and solidification of the PCM. EnergyPlus will be used to estimate heating and cooling energy use for the whole building. It will use Nablus weather data from a Typical Meteorological Year file, along with defined occupancy schedules and heating and cooling settings. The building will first be simulated without PCM, and the results will then be compared with those of the different PCM cases under the same conditions. Indoor temperature changes, the delay in peak heat transfer through the walls, and annual electricity use for heating and cooling will be assessed. The simulation approach will also be checked against published experimental results or established benchmark cases. Finally, electricity savings will be estimated as a percentage and in kWh per square meter of floor area per year. A simple payback period will be calculated using local electricity prices and the additional cost of the PCM and its installation. The practicality of using PCM in the selected building in Nablus will be evaluated, and the best balance between energy savings and cost will be identified among the tested materials and wall layouts.