<p>Latent thermal energy systems utilizing phase change materials (PCMs) offer an innovative solution to enhance thermal energy storage for solar applications. Despite their numerous advantages, these systems face limitations due to the complex heat transfer kinetics occurring during phase change. A deeper understanding of these fundamental phenomena is essential for developing reliable and effective devices. This study investigates the heat transfer process during the solidification phase (discharge) of PCMs in two distinct heat accumulator configurations. Two identical storage tanks were constructed, differing only in the placement of the PCM. In the first configuration, the paraffin is integrated directly into the tank’s lateral section, while in the second, the paraffin is located at the center of the tank. This experimental setup enabled discharge experiments to be conducted at three distinct withdrawal capacities. The kinetics of heat transfer during solidification were analyzed by measuring temperature variations at several points within the PCM and tracking the movement of the solid–liquid interface over time, providing a detailed analysis of the solidification process. Comparison of these two configurations provides new insights into optimizing thermal energy storage systems for solar energy applications.</p>