太陽能具備乾淨、可再生與無量限制等多項優點，而Solar Cell是直接將太陽能轉化為電能之技術。現今Solar Cell製作技術發展成熟，在大部分的現代化產品上都有應用，但現階段Solar Cell效率依然是目前最大的問題。針對此問題，本報告提出了一個Solar Cell電能循環系統並對其作初步分析。本研究具體內容為利用白光LED與Solar Cell及充電電池模組的組合來進行相關之研究，主要為利用LED對Solar Cell照射，並對充電電池進行充電，進而以充電電池之電力來回授驅動同一LED，藉由持續對Solar Cell進行照射以產生電能的循環，並同時對此系統進行相關量測，且將所獲得之數據提出分析，以作為今後本電能循環系統改善之依據，以期獲得一個最適化之電能循環系統。

We investigated the charge efficiency of rechargeable battery charged by solar cell Iiluminated by white LEDs. It is found that the charge efficiency depends strongly on the angle of the incited light emitted from the white LEDs. In addition, It is found that the outputs of the solar cell are not strongly dependent on the distance between the white LEDs and and the solar cell. Furthermore, the number of the white LEDs is also found to be an important parameter to affect the charge efficiency. For realizing an electrical power recycle system utilizing solar cell and LEDs, it is required to carry out more investigation.