智慧型動態複合運輸系統節能減碳之定價策略

Pricing Strategies in Energy Saving and Carbon Reduction for Dynamic Multi-modal Intelligent Transportation Systems

節能減碳乃現今世界各國施政之重要方針，其中運輸部門對溫室氣體中之二氧化碳排放具明顯的份量，為減少運輸工具所排放之二氧化碳，各國政府積極投入環保及節能效率高之大眾運輸系統優化並鼓勵民眾搭乘，藉此減少私人運具之使用，達成節能減碳之目標。為引導民眾搭乘大眾運輸系統，本研究探討私人運具油價、停車費及公車票價3 項影響民眾選擇運具之成本因子並制訂定價策略，交互變化成本因子，促使私人運具旅次移轉，進而達成節能減碳之目標。研究中運用一動態複合運具選擇與旅次指派模式 (Dynamic Multiple Mode Selection and TripAssignment Model, DynaMMSTAM) 完成節能減碳定價策略分析，運算過程中DynaMMSTAM 分別以一動態複合大眾運輸旅次指派模式 (TAM-MAPTS) 及一動態道路旅次指派模式 (DynaTAIWAN) 求得大眾運輸旅次指派及個人運具之路徑指派，以旅行成本函數計算兩系統之個別旅行成本，再以最小旅行成本之法則 (minimum path cost theory) 比較兩者成本執行運具選擇，進而計算旅次移轉量，達成減碳效益之評估。研究中制訂3 組定價策略並運用於一簡化高雄市模擬路網，進行成本因子間交互輪流調動對節能減碳影響之分析，探討減碳目標變動時，各定價策略達成減碳目標之定價組合。3組定價策略包括單項成本因子調整、2項成本因子輪流調動、3項成本因子輪流調動策略之運用。定價策略中，私人運具油價、停車費及公車票價分別於30 ~ 45元／公升、30 ~ 50元／次及12 ~ 0元／次區間進行減碳效益分析，依序交互輪動停車費、票價及油價。分析結果顯示，交互運用停車費及公車票價將使節能減碳之成效最為顯著，多重變數於複合效應促使下，減碳效益大於單一變數，但於執行層面上卻也面臨較複雜之問題，故政府執行節能減碳之策略除必須考慮使用效益較大之多重因子輪流調動方式外，亦必須考量其政策執行之可行性，定價策略應視CO2 之減量目標彈性使用，並盡量以單一變數之定價為主，多重變數定價為輔。

Carbon emission reduction is now an important principle of governancearound the world. Of all sectors, transportation plays a major role in carbondioxide emission. In order to reduce CO2 emission from the transport sector,governments must become actively involved in environmental protection and strivefor energy efficiency in transportation systems. To reach the goal of carbonreduction, people are encouraged to take public transit and reduce the use ofprivate vehicles.In this study, Dynamic Multiple Mode Selection and Trip Assignment Model(DynaMMSTAM) is applied to deal with dynamic multiple mode choice and tripassignment tasks. DynaMMSTAM includes two models, TAM-MAPTS andDynaTAIWAN. TAM-MAPTS, the transit trip assignment model, is first used toobtain the transit travel costs for all trips, and then, the model appliesDynaTAIWAN, the private vehicle trip assignment model, to calculate the privatevehicle travel cost for each trip. The minimum travel cost criteria are used todecide the mode selection for each individual trip. Through the accumulation ofmileage travelled by the private vehicle, the total amount of CO2 emission can becalculated. The idea is trying to lead the private vehicle users to use public transitso as to reduce CO2 emission. That is, to either reduce the transit cost or increasethe passenger car travel cost.Three cost factors including parking fee, oil price, and transit fare affectdirectly the traveler’s mode choice. Appropriate pricing of these cost factors canresult in the effective change in the impact of carbon reduction and reaching thenational reduction goal. Three pricing strategy groups defined in the study areapplied to a simplified Kaohsiung analogue network by alternatively changing thethree cost factors. The three groups include single cost factor pricing strategy,alternative pricing strategy for two cost factors, and mobilization of all three costfactors.Analyses have shown that multiple variable pricing strategies promote more carbon reduction benefits than a single variable due to the compounding effect.However, the government needs to consider not only the price elasticity but alsothe feasibility when implementing the carbon reduction strategies. Therefore,pricing strategies should be applied flexibly in the consideration of CO2 reductiontarget. As far as possible, the single variable pricing strategy should be the basis,while applying the multi-variable pricing strategy as a supplement.