日益嚴重的全球暖化問題，使提倡節能減碳的議題更加受到重視。其中交通工具產生的廢氣，一直被大家視為造成全球暖化和空氣汙染的主因之一，台灣對機車的依賴程度較高，機車持有率高達58.8%。台灣政府近20年來，積極推動電動機車的發展，但電動機車市占率至今不到4%。
有鑑於此，本研究使用擴散模型對台灣電動機車市場的模型進行預測，常見的擴散模型有Bass、Gompertz、Logistic模型，過往皆廣泛應用於預測產品的銷售趨勢上。本研究將影響台灣電動機車市場發展的因素納入至模型中，加入部分的歷史資料進行模型的配適，再從三款模型結果中挑選最能符合電動機車發展趨勢的模型，採用其估計出的參數進行後續車輛數和碳排放的預測。
為進行長期的預測，建構具有反饋機制的系統動態模型，根據擴散模型估計之參數結果帶入系統動態模型之中，能使系統動態模型更能符合實際電動機車之需求趨勢。建構系統動態模型，除了能釐清各市場驅動因子如何影響電動機車市場需求，更能透過反饋系統使預測更貼近現實的情境。
最後透過各情境的結果可以看出補助金額對電動機車需求有很大的影響，補助的開始時間點對電動機車最後需求影響不大，但對補助的總花費有很大的影響，另外政府如果推行相關利基政策進行產業的輔助，推行效果更加顯著；限制燃油機車銷售開始的時間沒有明顯差異，但限制幅度的不同就有明顯的差異，限制幅度越大電動機車需求越高；國內生產毛額成長幅度越高的情境下，電動機車需求也越高。

In this study, we use diffusion models to predict the growth of the electric scooter market. Common diffusion models include Bass, Gompertz and Logistic models. We use part of the historical data to fit the model, select the model that best fits the future market trend of electric scooters. The best model is used with estimated parameters to forecast demand and the reduction of carbon emissions. To make long-term predictions, we construct a system dynamics model. It can clarify how each market factor affects the demand of electric scooters and make the prediction closer to the real world system. Finally, as the result of the simulation, the subsidy amount has a great impact on the demand of electric scooters. The start of the subsidy has no obvious impact on the demand, but it affects the final total cost. There are obvious differences in the sales level of restricted fuel scooters, with higher restrictions and higher demand. We find the higher the GDP growth rate, accompanied by the higher demand. The greater the market saturation, the higher the demand of electric scooters.

Key Words: Electric scooter, Carbon emissions, Diffusion model, System dynamics

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