The authors [24] present a numerical study on the performance of two structures made of concrete: parallel plates and blocks with multiple tunnels. Similarly, the author [25] developed an effective numerical model for heat transfer between HTF interacting with filler material. Subsequently, they extend their application to a multi-tunneled blocky thermocline [26], introducing a modified heat transfer coefficient that corrects the lumped systems analysis for this structure. Finally, the study of [27] showed the corrected coefficients for the same structure and the parallel plate and rod bundle configurations. On the other hand, [PERSON]. [28] analyzed the economic viability of the parallel plate configuration, concluding that the system costs increase by 9% and the thermal efficiency decreases by 7%, compared to a porous bed thermocline tank. Finally, the thermal efficiency for the porous bed and the three mentioned structures in concrete material was presented by [24], concluding that the structured configurations can equal or exceed the efficiency of the porous bed configuration through small characteristic lengths. It involved a small-sized tank and materials with better thermal properties. In other studies, [PERSON]. [29; 30] proposed using PCM of different alloys to store thermal energy in industrial processes. Likewise, [PERSON]. [31; 32] investigated high-temperature latent heat storage, which has increased attention owing to its potential to integrate renewable energy sources. Studies dedicated to the numerical and experimental optimization of TES have shown great interest in the scientific public. For example, using conjugate heat transfer analysis, [PERSON]. [33] evaluated the impact of critical parameters and flow conditions on latent heat TES systems. Also, [PERSON]. [34] optimized the latent heat and melting temperature values of multilayer PCM in thermocline tanks for CSP plants. Considering the advances in thermal storage systems coupled with CSP technology, the main objective was to investigate the application of the system in a case study where a constant supply of off-grid electrical energy was required on a small scale. Currently, the study case depends on generator sets or hybrid systems using diesel fuels instead of RES. As a result, the proposal consists of a numerical model assessment of the design of a block-structured thermocline TES system with multiple tunnels based on base change material using CSP. The document presents a novel numerical model for designing a thermal energy storage system with multiple tunnels using phase change material tailored explicitly for off-grid industrial applications like mining in Chile. This system showcases a structured thermocline tank configuration that addresses thermal ratcheting issues, ensuring structural integrity. The innovation lies in its application to small-scale off-grid operations, demonstrating stable thermal behavior, low degradation, and high efficiency (~92%) over significant storage times (up to 13 h) and capacities (384.8 kWh). Its compact, modular, and economically competitive design further highlights the originality of the model, making it a viable option for concentrated solar power applications in remote mining operations.