This study aims to determine which thermal energy storage (TES) system is most suited for a concentrated solar power (CSP) plant. The question is which the best TES system, whether utilizing a single metal hydride or employing dual metal hydrides with or without reaction heat recovery via phase change material (PCM). The authors noted that no studies have been conducted to address this question thus far. Consequently, the primary aim of this paper is to compare three different TES systems in order to ascertain the viability, efficacy, and performance of the appropriate TES system. The examined TES systems included: (i) TES system 1, based on a single metal hydride tank coupled to a hydrogen tank through an H compressor; (ii) TES system 2, based on paired metal hydride tanks without recovering reaction heat; and (iii) TES system 3, based on paired metal hydride tanks incorporating a PCM for reaction heat recovery. To simulate and evaluate the performance of the three TES systems under various operating conditions, a mathematical model and computer program were created and successfully verified. By examining into their thermodynamic performance and practical viability, this study attempts to provide the strengths and limitations of each system. A comparison of the three TES systems' performance indicators indicates that the TES system 1 has the potential to provide a specific power output of 500.8 W/kg of alloy, which is 50.1 % and 76.4 % greater than the TES systems 2 and 3, respectively. With a volumetric storage capacity of 755 MJ/m, the TES system 2 outperforms the other two TES systems by around 40 %. The TES system 3 can operate with 85.9 % energy storage efficiency. This efficiency is 30.3 % higher than that of the TES system 1 and 10.2 % higher than that of the system 2. Ultimately, the decision to choose either a TES system based on a single metal hydride or one involving paired metal hydrides is hinges on the specific requirements, limitations, and priorities of the TES system under consideration.

中文翻译：

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单一金属氢化物与成对金属氢化物热能储存系统对比分析

本研究旨在确定哪种热能存储 (TES) 系统最适合聚光太阳能发电厂 (CSP)。问题是哪种 TES 系统最好，无论是使用单一金属氢化物还是使用双金属氢化物，无论是否通过相变材料 (PCM) 回收反应热。作者指出，迄今为止尚未进行任何研究来解决这个问题。因此，本文的主要目的是比较三种不同的 TES 系统，以确定适当的 TES 系统的可行性、有效性和性能。所检查的 TES 系统包括： (i) TES 系统 1，基于通过 H 压缩机耦合到氢气罐的单个金属氢化物罐； (ii) TES系统2，基于成对金属氢化物罐，不回收反应热； (iii) TES 系统 3，基于成对的金属氢化物罐，并结合了用于反应热回收的 PCM。为了模拟和评估三个 TES 系统在不同操作条件下的性能，创建了数学模型和计算机程序并成功验证。通过检查其热力学性能和实际可行性，本研究试图提供每个系统的优点和局限性。三个TES系统性能指标的比较表明，TES系统1有潜力提供500.8 W/kg合金的比功率输出，分别比TES系统2和3高50.1%和76.4% 。 TES 系统 2 的体积存储容量为 755 MJ/m，比其他两个 TES 系统高出约 40%。 TES系统3可以以85.9%的能量存储效率运行。该效率比 TES 系统 1 高 30.3%，比系统 2 高 10.2%。最终，选择基于单一金属氢化物的 TES 系统还是涉及成对金属氢化物的 TES 系统取决于正在考虑的 TES 系统的具体要求、限制和优先事项。