Selection of Encapsulated Phase Transition Materials for Efficient Interseasonal Accumulation and Storage of Solar Energy for Heat Supply of Civil Buildings

In the context of the global transition to sustainable development and energy efficiency, renewable energy sources (RES) are becoming increasingly important. Solar energy, as one of the key elements of renewable energy sources, is an unlimited and environmentally friendly resource that can significantly reduce the carbon footprint and increase the energy security of countries. This is especially true for civil buildings, the heat supply of which accounts for a significant part of primary energy consumption. The article presents the results of a study of encapsulated phase-transition materials, in particular microcapsules filled with paraffin, to improve the efficiency of interseasonal accumulation of solar energy in heating systems of civil buildings. In the course of the work, innovative encapsulation methods aimed at improving the heat-transfer properties of the battery and minimizing heat losses were studied. Key thermophysical properties of materials, such as latent heat of fusion, phase transition temperature, and stability during multiple heating and cooling cycles, were assessed. The presented results allow expanding the possibilities of using such systems for efficient long-term storage of thermal energy, which is especially important for providing heat during off-season periods.