以微藻為生質原料所發展的再生能源具有很大的潛力，因其高生長速度、高油脂含量、固碳效率高等，這些優點使微藻成為目前熱門生質原料的研究主題，微藻高油脂含量可藉由轉酯化反應，將其轉為生質柴油，本研究利用Aspen Plus以及實驗文獻數據設計出一微藻能源系統，其程序包含微藻培養、收集、除水、破壁、藻油萃取、乾燥以及生質柴油製造程序與煤共汽化發電程序，此系統模型建立於GAMS中，模型屬於非線性整數規劃(MINLP)，在數學規劃時，可以同時考慮不同操作策略的組合以及操作變數的數值，找出程序中全域最優化的碳排結果。
　　此系統可視為一種分散式能源系統，電力產生的方式為利用汽化所得的合成氣燃料，通入固態氧化物燃料電池與氣渦輪(SOFC/GT)之混合發電系統，汽化的原料是再利用微藻殘渣作為進料，以利提升整體能源效率。系統產物為由藻油轉化而得的生質柴油與從汽電共生系統所產生之電力，藉由程序優化後，發電系統的效率為52.99%其每度電的相當碳排放0.3379 kg-CO2/kW hr。最後我們藉由生命週期分析(Life cycle analysis)，來評估此系統對於溫室效應的減緩是否有益。
呈現結果以每單位燃料能量含量之碳排放作為基準，將此系統微藻生質柴油與石化柴油作為比較，結果顯示此系統所產生之生質柴油其石化燃料使用量與生質能源輸出的比值為0.4778，其單位能量的碳排為47.27 e g-CO2/MJ，數據顯示出微藻柴油的總碳排與石化柴油相比，降低了46.01%，可應證微藻柴油具有潛力可作為新的替代柴油。

We built up a microalgal energy system including cultivation, dewatering, harvesting, extraction, biodiesel production, gasification, and power output. The aim of biodiesel production coupling with integrated gasification fuel cell (IGFC) system is to completely utilize the whole microalgae, including the oil and the residual part. The model built up is based on the results from Aspen Plus®, experimental data, and literature. The mathematical formulation of the model is coded in GAMS® as a mixed-integer nonlinear programming (MINLP) problem. Through life cycle analysis (LCA) under the constraints of mass balance and energy balance, we quantify the greenhouse gas emission of per unit energy content of biodiesel. Bilinear relaxation with Big-M piecewise partitions is applied in the algorithm to enhance the performance of computing nonconvex bilinear term.
The final results of global warming potential (GWP) indicate that the system with the scale of nearly 300-ton biodiesel per year has positive greenhouse gas (GHG) reduction performance compared to fossil diesel. The value of GWP of biodiesel generated from this system is 47.27 g e-CO2, which reduces 46.01% of GHG emission. Therefore, we can conclude that microalgae have the potential to be the candidate of renewable energy.

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