The thermal energy storage plays a fundamental role in improving the efficiency and reliability of solar energy applied in the building engineering and its conventional techniques are Latent and Sensible Heat Thermal Energy Storage (LHTES and SHTES). To analyze the thermal performance of LHTES-Tank and SHTES-Tank with paraffin RT55 and water as thermal storage mediums respectively, a contrastive experiment was done. The experiment included 5 thermal charging and discharging cycles by changing Heat Transfer Fluid (HTF) temperatures between 20 °C and 80 °C. Results show the thermal discharging was more difficult than thermal charging in LHTES-Tank. Most paraffin could melt entirely but cannot solidify completely, while around 19.36% of paraffin in LHTES-Tank was always solid or liquid, and thereby acted as a dead mass. Paraffin had the higher thermal storage capacity than water only in the phase-change temperature range, so water may play the thermal storage potential more efficiently than paraffin under the large HTF temperature difference. Also based on this reason, LHTES-Tank had only a little advantage in thermal and exergy efficiency compared to SHTES-Tank under the HTF temperature of 20°C–80 °C, but its optimization potential was showed to be very large. Finally, the main existing problems were summarized according to thermal behavior of LHTES-Tank.

热能存储在提高建筑工程中使用的太阳能的效率和可靠性方面起着根本性的作用，其常规技术是潜热和显热热能存储（LHTES和SHTES）。为了分别分析以石蜡RT55和水为储热介质的LHTES-Tank和SHTES-Tank的热性能，进行了对比实验。该实验包括通过在20°C至80°C之间改变传热流体（HTF）温度进行5个热充电和放电循环。结果表明，在LHTES-Tank中，热放电比热充电更困难。大多数石蜡可以完全熔化但不能完全固化，而LHTES-Tank中约有19.36％的石蜡始终是固体或液体，因此起死块的作用。仅在相变温度范围内，石蜡比水具有更高的储热能力，因此，在大的HTF温差下，水可能比石蜡更有效地发挥储热潜力。也是基于这个原因，在20°C–80°C的HTF温度下，与SHTES-Tank相比，LHTES-Tank在热效率和火用效率方面仅占很小的优势，但是其优化潜力却非常大。最后，根据LHTES-Tank的热行为总结了主要存在的问题。在SHF-Tank在20°C–80°C的HTF温度下，与SHTES-Tank相比，LHTES-Tank在热效率和火用效率方面仅占很小的优势，但是其优化潜力却非常大。最后，根据LHTES-Tank的热行为总结了主要存在的问题。在SHF-Tank在20°C–80°C的HTF温度下，与SHTES-Tank相比，LHTES-Tank在热效率和火用效率方面仅占很小的优势，但是其优化潜力却非常大。最后，根据LHTES-Tank的热行为总结了主要存在的问题。