經濟部在2008年通過「永續能源政策綱領」，將太陽能熱水系統納為行動方案之一。然而，目前針對太陽能熱水系統研究，多數以家用太陽能熱水器為主，公用太陽能熱水系統較家用太陽能熱水器相對複雜，因此，目前甚少有研究。本文以四個陸軍兵舍自行設計、監造、發包執行的太陽能熱水系統實際使用成效為研究主題，評估結果僅有台中市兵舍具有成本效益，高雄市兵舍設計供應量超出實際需求量達2倍， 這顯示在無實務設計規範的狀況下，設計不容易符合需求。在回收年限方面，如果維持各兵舍原有熱水供水管路系統及各自僅有的一處浴室，假設年維護運轉費用為設置費用5%，本文以成本回收年限=(總投資成本-補助申請補助金額)/（每年節省能源費用-年維護運轉費用）估算，則除了高雄市兵舍外，其餘三個兵舍太陽能熱水系統回收年限均在適當使用年限內。最後，本文提出一個包括操作維護的太陽能熱水系統設計規範，以提升後續使用者的舒適及安全性。Solar water heating system (SWHS) is one of the action plans of Sustainable Energy Policy Guideline promulgated by Ministry of Economic Affairs in 2008. However, at the present stage, most studies on SWHS focus on household SWHS. Public SWHSs are relatively complicated and thus with very few studies. This study aimed at assessing cost-effectiveness of practical usage for four SWHSs self-designed and constructed by Army Post (AP). The results indicate only Taichung AP acquires cost-effectiveness of practical usage. The hot-water supply in Kaohsiung AP is twice as big as the demand. This implies that the design is hard to reach the demand if no practical design norm is available. For the estimation of cost-recovery years, suppose the original hot-water piping system with only single bathroom in every AP is maintained and assume 5% of the total capital cost as annual operation and maintenance cost, this study computed cost-recovery years as (total capital cost – government subsidies)/(annual energy-saving cost – annual operation and maintenance cost). Except for Kaohsiung AP, the other three are within time of proper SHWS usage for cost recovery years. In addition, this study also reviewed the control of electrical booster to avoid from ineffective usage of hot-water in solar collector or causing unnecessary power consumption. Finally, this study proposes a design norm for a SHWS covering operation and maintenance to enhance comfort and safety for followers.
