現今海運已成為國際間運輸的主流，全球貿易有90%都透過海上運輸， 然而大部分的商用船舶多使用重油為燃料，造成大量環境汙染。船舶運輸 產生的SOX、NOX 及CO2e 排放量分別占全球的12%、13%、2.8%，對於環 境的影響衝擊甚大。液化天然氣 (LNG) 因具有環保、安全性高且符合國際 排放量標準，在國際上已成為船舶替代燃料的最佳選擇。因此，本研究探 討臺灣區域兩岸及近海5 艘營運中的客貨滾裝船，以EPA 及洛杉磯港模型 導出船舶以LNG 替代傳統燃料對環境影響之差異，並以SOX 及NOX 每延 噸海浬排放量進行載運率與排放量之情境分析。實證分析結果為，不論以 EPA 模型推估或是以洛杉磯港模型推估，以LNG 替代傳統燃料，SOX 排放 量將降低90%以上、NOX 排放量將降低70%以上、CO2 排放量將降低13% 以上，顯示出LNG 對於降低環境汙染確有明顯效益。在情境分析中，研究 結果得出，以航線類型區分，應以兩岸航線優先推動LNG 較具效益；若以 船舶類型區分，應以傳統船優先推動LNG 較具效益。

Today, maritime transport has become an international mainstream. 90% of global trade depends on maritime transport, but most of the merchant vessels use Heavy Fuel Oils(HFOs) for ship propulsion, causing heavy environmental pollution.The contribution of ships to global emissions can be indicated as being in the following:sulfur oxides(SOX), 12%；nitrogen oxides(NOX), 13%；carbon dioxide equivalent(CO2e), 2.8%. Liquefied natural gas (LNG), due to environmental friendly, safely and meet international emissions standards , has become the best choice for ship alternative fuel. The aim of the research presented in this paper is to analyse five offshore ships which operating in Taiwan, and to explore the environmental influences of using LNG alternative to traditional fuels by EPA and PLOA models, and further to carry on scenario analysis of SOX and NOX emissions of per ton-miles. Results show that LNG leads to a reduction of 90% SOX emissions and 70% NOX emissions and 10% CO2 emissionsin at least both modes. In scenario analysis, results show that in order to distinguish the type of route, the cross-strait routes should be a priority to promote LNG fuel; in order to distinguish the type of ship, traditional vessels should be a priority to promote the LNG fuel.