船舶電力功因校正之經濟效益分析

Economic Analysis of Power Factor Correction for Marine Vessels

電力功率因數（功因）校正（power factor correction）技術於船舶節能應用已有實際案例。從經濟效益觀點來看，節能投資方案的規劃必須考慮因節能改善方案的導入所能獲得的效益及所需之投資成本，以判斷該方案是否具投資效益。本文主要目的為建立一套船舶電力功因校正之經濟效益分析模式。針對一般商船供電系統在其航次內不同作業模式下之實功、虛功、功率因數等進行實測，配合柴油發電機油耗的量測，分析裝設自動功因校正器後可能帶來的節能減碳效益，並使用兩種標準經濟效益分析方法，進行雜貨輪功因校正成本效益實例分析。基本經濟參數之敏感度分析也被加以執行，以減少參數變動對分析結果的影響並找出關鍵參數。分析結果可協助船廠及船東評估功因改善方案之執行效能及建立其商業案例，以決定投資方案之回收年限（return on investment，ROI）。 Application of power factor correction techniques to energy savings in practical ship electric power systems have been studied. From an economic viewpoint- the energy-saving benefits due to introduction of the power factor correction option and investment costs required should be considered in planning of the investment for judging whether the improvement option is economic or not. This paper aims to establish a set of benefit-cost analysis model for power factor correction utilized in ships. The active power, reactive power, power factor, and diesel electric engine's oil consumption for a practical merchant vessel power system during different operating conditions are measured and analyzed. The possible benefits for energy-saving and emission reduction after installing automatic power factor corrector (APFC) devices are identified and a benefit-cost analysis of APFC for a practical bulk carrier is performed by using two standard economic analysis methods. Sensitivity of basic economic parameters to analysis results is also performed to reduce effects of input parameters on the analysis results and to determine the critical parameters. The proposed analysis model developed in this paper can assist ship building corporations and ship owners in assessing performance of the power factor improvement option and building business cases for determining return on investment (ROI).