混合整數線性規劃應用於生質能源供應鏈研究－以北臺灣地區稻稈熱裂解發電為例

Applying Rice Straw in Bioenergy Supply Chain Management Using Mixed Integer Linear Programming: A Case Study of Northern Taiwan

盧翊程(Yi-Cheng, Lu)

指導教授 ： 邱祈榮

國立臺灣大學/生物資源暨農學院/森林環境暨資源學研究所/碩士(2019年)

https://doi.org/10.6342/NTU201900433

摘要

近年來全球對於能源的需求日益迫切，尤其是發展中的再生能源。臺灣地區能源多數仰賴進口，唯有推動能源多樣性、提升能源自給率才能穩定能源供應。然而在臺灣地區生質能源發展屢屢受限，如能源效率不如燃煤、後勤物流成本高以及原料供給量不確定性，使得生質能源供應鏈中占比甚少。本研究為解決上述問題，以稻稈剩餘資材作為生質能源發電之原料，使用熱裂解技術生成電能，同時解決傳統稻稈去化方式的碳排放問題。熱裂解所生成的產品亦能減低碳排放，因此值得吾人進行評估。
本研究提出一系列生質能源發電廠選址方案，在滿足稻稈去化需求的條件下，發展出兼具投資可行性與固碳效益之供應鏈模型。本研究首先針對北台灣地區稻 作資源進行盤點，估算生質能源原料的供應量；再來建構供應鏈模型，設定目標式、參數式和限制式，利用混合整數線性規劃(MILP)求解；最後，針對稻稈熱裂解發電的各項成本與效益進行成本效益分析，判斷投資可行性，並假設情境探討可能的投資風險，進行敏感度分析，以利政府或投資者進行決策。
本研究選取北台灣的桃園市與新竹縣市行政區的稻田作為腹地，所得到的稻稈原料量估計為 82,740 公噸。在供應鏈模型中，成本部分計入收集、運輸、儲藏、預處理、轉化成本，效益部分計入售電收益、減碳收益、產品收益。以最小化成 本為目標，MILP 求解結果顯示小型分散型生質能源發電廠較為有利，且僅需 4 座生質能源發電廠，分別設於大園、新屋、竹縣、楊梅等地，即可滿足北台灣稻稈去化需求。在淨現值計算的部分，分散型生質能源發電廠 NPV 約為 3.26 億元新台幣，明顯優於前者的1.42億元新台幣。IRR 計算中，分散型生質能源發電廠為13%， 優於前者的8%，營利指數也以2.43略高於前者的1.82。最後在折現還本期的表現，小型生質能源發電廠能在 6.02 年後回本，相較於前者需要8.55年。
最後本研究進行情境分析與敏感度分析，將稻稈剩餘資材的收購費用降為0元，則可大幅減支出，變動成本從48.58億元新台幣降為37.00 億元新台幣。而另 外情境二則給予售電更高的單位電價，使得收益部分最多增加 7978 萬元新台幣。 敏感度分析中則以電力成本變動影響最大，倉儲成本次之。

關鍵字

生質能源 ； 碳排放 ； 生物炭 ； 供應鏈最佳化 ； 混合整數線性規劃

並列摘要

In recent years, the global demand for energy has become increasingly urgent, especially in the development of renewable energy. Most of Taiwan's energy depends on imports. Only by promoting energy diversity and increasing energy self-sufficiency can we stabilize energy supply. However, the development of biomass energy in Taiwan is often limited. For example, energy efficiency is not as good as coal burning, logistics logistics costs and raw material supply uncertainty, making the proportion of raw energy supply chain very small. In order to solve the above problems, this study uses rice straw surplus materials as raw materials for biomass energy generation, uses thermal cracking technology to generate electricity, and solves the carbon emission problem of traditional rice straw removal methods. The products produced by thermal cracking can also reduce carbon emissions, so it is worthy of our evaluation.
This study proposes a series of site selection schemes for biomass energy power plants. Under the conditions of meeting the demand for rice straw removal, a supply chain model with both investment feasibility and carbon sequestration benefits is developed. This study firstly conducted an inventory of rice resources in northern Taiwan, estimated the supply of raw materials for raw materials, and then constructed a supply chain model, setting target, parametric and restricted, using mixed integer linear programming (MILP) to solve; Cost-benefit analysis of various costs and benefits of rice stalk thermal cracking power generation, judging investment feasibility, and assuming the situation to explore possible investment risks, and conducting sensitivity analysis for the government or investors to make decisions.
In this study, the rice fields in Taoyuan City of North Taiwan and the administrative district of Hsinchu County were selected as the hinterland, and the amount of rice straw raw materials obtained was estimated to be 82,740 metric tons. In the supply chain model, the cost component is included in the collection, transportation, storage, pre-processing, and conversion costs, and the benefit component is included in the sales revenue, carbon reduction income, and product revenue. In order to minimize the cost, the MILP solution results show that the small-distributed biomass energy power plant is more advantageous, and only four biomass energy power plants are needed, which are located in Dayuan, Zhinwu, Zhushien, Yangmei and other places. North Taiwan rice stalk de-chemical needs. In the part of the net present value calculation, the NPV of the distributed biomass energy power plant is about NTD 326 iv million, which is significantly better than the former's 142 million NTD. In the IRR calculation, the dispersed biomass energy power plant is 13%, which is better than the former 8%, and the profit index is also 2.43 slightly higher than the former 1.82. Finally, in the current performance of discounted, the small biomass energy power plant can return to the original after 6.02 years, compared with 8.55 years compared with the former.
Finally, the study carried out the situation analysis and sensitivity analysis, reducing the acquisition cost of the remaining materials of rice straw to 0 NTD, can significantly reduce the cost up to NTD 1.1 billion. In addition, the second situation gives a higher unit price for electricity sales, which increases the income portion by up to NTD 7.9 million. In the sensitivity analysis, the change in raw material collection cost has the greatest impact, and the power cost is second.

並列關鍵字

biomass energy ； carbon ； emissions ； biochar ； supply chain optimization ； mixed integer linear programming

參考文獻

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