Thermal energy storage (TES) is an effective method to buffer solar fluctuation and enable Organic Rankine Cycle (ORC) to operate under steady and design conditions. Heat transfer and energy storage characteristics of TES systems under solar fluctuation need to be studied to better understand the practical energy storage process and provide guidance on design/optimisation of integrated TES-ORC systems. In this paper, the charging process of a shell-and-tube system containing molten salt as phase change material with/without ceramic foam enhancement over a whole sunny and cloudy day was investigated. For the same full charging cases, the total stored energy is different according to solar fluctuation, with a maximum difference of 17.9%. Strong solar radiation not only accelerates the energy storage rate but also improves the total stored energy. Rising solar radiation can also cause large total stored energy while the energy storage rate is slow. Oscillating solar radiation generates the least total stored energy among full charging cases, however, the energy storage rate is higher than that under rising solar radiation. Falling solar radiation leads to small total stored energy. Ceramic foam-enhanced molten salt is more sensitive to solar fluctuation while the total stored energy over the whole working day is improved by 33.2% on a sunny day and 29.1% on a cloudy day respectively.

热能储存 (TES) 是缓冲太阳波动并使有机朗肯循环 (ORC) 在稳定和设计条件下运行的有效方法。需要研究太阳波动下 TES 系统的传热和储能特性，以更好地了解实际的储能过程，并为集成 TES-ORC 系统的设计/优化提供指导。本文研究了以熔盐为相变材料的管壳式系统在整个晴天和阴天的充电过程。同样充满电的情况下，总存储能量会根据太阳能波动而有所不同，最大差异为17.9%。强烈的太阳辐射不仅加快了能量存储速度，而且提高了总存储能量。上升的太阳辐射也会导致总储存能量大，而能量储存速度慢。在充满电的情况下，振荡的太阳辐射产生的总存储能量最少，但是，能量存储率高于太阳辐射上升的情况。下降的太阳辐射导致总储存能量很小。泡沫陶瓷增强型熔盐对太阳波动更敏感，全工作日总储能在晴天和阴天分别提高33.2%和29.1%。下降的太阳辐射导致总储存能量很小。泡沫陶瓷增强型熔盐对太阳波动更敏感，全工作日总储能在晴天和阴天分别提高33.2%和29.1%。下降的太阳辐射导致总储存能量很小。泡沫陶瓷增强型熔盐对太阳波动更敏感，全工作日总储能在晴天和阴天分别提高33.2%和29.1%。