本研究的主要目地是以簡要且精確的數學模型，來探討發電機發電、冷卻水塔耗電與循環水出口水溫之間的關係，並藉由此關係來找出最佳的操作策略。本模型分為兩大部分，第一是分析發電機發電與循環冷卻水關係的部分，第二則是分析循環水水溫與冷卻水塔耗電關係的部分。第一部分我們藉由工廠提供的大量數據，將發電機排氣熱焓與蒸氣流量、冷卻水溫進行二維線性回歸，得到一相當精準的線性模型。而在第二部分，本文獻針對水塔的冷卻能力，將數據進行分類，並將各類別的數據分別進行線性回歸，得到一水溫與水塔風扇耗電量的線性關係。最後，結合兩部份的模型，即可得到最佳化的系統操作模式。這樣的結果提供我們一個精簡易懂的最佳化操作模式，不但運算複雜度低，且可以快速投入實際工廠應用，是個較為實用的數學模型。

The main purpose of this study was to use a brief mathematical model to explore the relationship between the outlet water temperature of cooling tower between steam turbine electricity generation and fan electrical consumption. The model was divided into two parts. The first was to analyze the power generation of the turbine and outlet water temperature. The second is to analyze the electricity consumption between fan power and water temperature. The first part we do the linear regression analysis on a large amount of datas of steam enthalpy, steam flow rate and water temperature to obtain a fairly accurate linear model. At the second part, we part the fan-related datas into several groups based on cooling capability, and do the linear regression analysis on each group data. At last, we combine the two model and obtain the optimization guide for the system. The result provided us an easy-to-understand optimization operation model, which is not only computationally inexpensive but also can be put into practical factory application. It is a very practical mathematical model for many industrial factory.

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