以藻類生產生質柴油之經濟效益評估

Abstract

隨著油價的高漲，環保意識的抬頭，發展新型態且乾淨的替代能源成為全世界的首要目標。由於生質柴油具有生物可分解性、不含硫、無苯環化合物、燃燒排放物質較無污染等特性，於最近幾年愈來愈受到人們的重視，是一種兼顧環保並可永續經營的替代能源。目前生質柴油大部份由如大豆、油菜及棕櫚等陸生作物的油脂所製成，此可能引發「與人爭糧」及「與糧爭地」爭議，由於藻類之生長速率較植物快速，使得以藻類製造生質柴油成為目前研究開發的重點，然國內卻幾無藻類生產成本相關的資料可循。有鑑於此，本論文針對國內以藻類生產生質柴油的各種情況加以分析其成本，應用敏感度分析探討各因素對生產成本的影響，並提出相關建議。 本論文設定三種藻類生質柴油程序及兩個藻類生質柴油情境，經由各項分析結果得到開放式培養系統、密閉式光生物反應器及異營醱酵槽培養程序產製藻油的成本及內部報酬率分別為22.73 元/公斤和8.91%、27.94 元/公斤和5.33%、24.83 元/公斤和5.44%。此外，由敏感度分析結果得到三項對藻類生質柴油經濟影響最大的因素，包括：(1)降低光合反應系統的建造成本；(2)增加藻體/油脂生產量；(3)高附加價值副產物的產量與價值或藻油售價。依此結果所得藻油成本仍無法與石化原油相比，但已與一般陸生油脂相近，未來仍有很大的機會能進一步降低成本，做為生質柴油的油脂料源。最後，本論文提出相關的微藻生質柴油產業經營管理與執行策略及未來能源藻類發展的建議，提供給國內對藻類生質柴油有興趣的人員參考，期能使其早日實現商業化生產。

With noticeable oil price hike and increasing protective consciousness of environment, it becomes the prime goal for all countries to develop new and clean alternative energy. Biodiesel has received much attention in recent years, since it is biodegradable, contains no sulfur and benzene compounds, and releases less pollutant substances after burning. Biodiesel is an alternative energy that is both environmental friendly and has sustainable operation achievability. Currently, most of the biodiesel is produced from vegetable oils of terraneous oil-crops, such as soybean, rape seed and palm oils. The production of biodiesel from microalgae is a newly emerging field due to it’s larger biomass, larger growth rate compared to those of oil-crops. However, it was rare investigated for the economic assessment of microalgal biodiesel in Taiwan. Therefore, the main purpose of this article was to study the cost of biodiesel from microalgae oil based on domestic conditions and the effects of the relative economic importance of each variable with sensitivity analyses, and then the suggests for future development of microalgae derived biodiesel were proposed. There were three production procedures and two scenarios for microalgal biodiesel being set in this article. By the analysis results, it was found that the cost and IRR(Internal Rate of Return) of algae oil production for open system, close system and fermentation were NT$22.7/kg and 8.91%, NT$27.94/kg and 5.33%, and NT$24.83/kg and 5.44%, respectively. Moreover, from ‘sensitivity analyses’ it is clear that the three most important factors for facilitation of microalgal biodiesel production systems are ： (1)The reduction of cultivation systems construction costs ； (2)The increase of biomass/algae oil yield ； (3)Extractable HVP value or oil commodity price. Those analyses obtained that the cost of microalgal oil remain in an higher stage compare with crude oil, but they are now approaching profitability compare with those of terraneous oil. They may be a raw material for biodiesel production with decreasing cost in the future. Finally, the suggestions of business management and execution strategy for biodiesel production by microalgae, and the future researches of microalgae were proposed. Those could be a reference for people who are interesting in the development of microalgal biodiesel.