本研究旨於針對浮置於水域表面之光電池模組系統，藉於其背面附置單/雙層相變化材料微膠囊模組，以動態數值模擬分析光電池於日照期間其溫度變化及發電效率情形；此外，並探究相變化材料微膠囊層日照期間所儲存熱能於夜間釋放至底部水層之保溫特性。在文中，數值模擬分析針對台南地區夏/冬季節環境條件(包括:空氣/天空溫度、風速、日照量、水層溫度與流速之動態變化)，改變相變化材料微膠囊熔點(夏季30~26℃、冬季18~16℃)和其夾層厚度(5cm、3cm)等參數，探討光電池模組系統與環境間熱交換動態變化及其所致發電效能的影響。研究結果顯示在夏季環境下，附置單層厚度5cm之相變化微膠囊層(其熔點為30℃)於光電池模組能有效地提升其發電效率及發電量；而在冬季環境下，則附置雙層厚度均為5cm之相變化微膠囊層(其熔點分別為18℃/16℃) 於光電池模組夜間可有效釋放熱量至底層水域，發揮水層保溫功效，而抑制夜間輻射冷卻災害。

This paper aims to explore, via dynamic simulations , the efficacy of attaching single/two layers of microencapsulated phase change material (MEPCM) to a water-surface floating photovoltaic module for managing its thermal environment and thus improving its efficiency of electricity generation under various daily operation conditions. The numerical simulations undertaken focus primarily on the effects of the thickness (5cm and 3cm) as well as the melting temperatures, which were 26℃-30℃ for the summer season and 16℃-18℃ for the winter season, respectively, of the MEPCM layers on their thermal management and electric efficacy under the typical weather conditions locally observed during the summer and winter seasons at Tainan area of Taiwan. The numerical results clearly show that under the summer weather condition considered, the electrical performance of PV module can be effectively enhanced by using a single layer of MEPCM of 5 cm in thickness with the melting point at 30℃; while under the winter weather condition simulated, the PV module attached with two layers (with thickness fixed at 5 cm) of MEPCM having the melting temperatures, respectively, at 18℃ and 16℃ appears most effective in releasing thermal energy downward to and thus alleviating the radiation cooling over the water layer during the night time.

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