| 摘要: | 營建業當前所面臨的困境為傳統施工品質日益受到考驗和缺工問題，伴隨著科技發展和少子化的趨勢下，預鑄工法能逐漸成為傳統場鑄的替選方案。預鑄混凝土的領域分類大致可分為隧道環片、預鑄混凝土帷幕牆、體育館看台、結構預鑄樑、柱和樓板。預鑄工法有效解決勞動力不足問題，甚至在不受氣候影響，解決嚴冬或炙熱無法施工情況。預鑄工法強調以工業化手段提升建築品質，採用同步工程策略，達到快速興建的目的，減少能耗和降低環境噪音汙染。
我國預鑄產業中，結構預鑄主要以「潤弘精密股份有限公司」和「亞利預鑄工業股份有限公司」。預鑄混凝土工廠的生產營運會產生「內部成本」與「外部成本」。與前者相關之營收利潤能夠透過上市公司公開的財務年報得知，準確地檢視某公司營運狀況，為某公司永續經營重要的指標。至於後者，則泛指對於社會或者其他個人部門造成的影響與衝擊。電力為工廠營運主要的消耗能源，電力之生產所造成的溫室氣體排放，包含氮氧化物、二氧化碳，是影響全球暖化的重要因素，二氧化硫是形成酸雨的原因，發電過程中排放的懸浮顆粒，為嚴重導致呼吸道症候群的主因。綜上所述，本研究除探討預鑄混凝土工廠本身的「內部成本」項目外，尚考量預鑄成品在生產過程中電力需求所造成的「外部成本」。提供預鑄混凝土工廠電力消耗所造成的外部成本的影子價格估計、預鑄施工建築的節能減碳之貨幣化效益評估。
節能減碳為現在世界經濟發展的趨勢，在固定額度碳權配給下，衡量受評單位(DMU)的地區之間或時空維度之間的碳權就可以進行交易，使得碳排放成本內部化整體經濟發展可以達到最大的效益，並兼顧使用者付費之社會正義，但如何在碳交易與經濟成長之間的互動，是一項主要議題，目前用來探討碳權交易機制的模型主要有三種：無碳權交易模型(NT)、空間碳權交易模型(ST)與時空碳權交易模型(STT)。此外，現有DMU之運作方式是否偏離最優DMU的產出的方向(或稱之為最優產出一致性)，是以cosine的函數予以表示，其併同麥式指標之效率變動，即效率改善程度，可以衡量DMU績效，可找出DMU在生產過程的缺失，並且進行改善，即最優產出一致性vs.效率改善。本研究採用meta-DEA的模型進行求解邊際生產力，並窮舉不同權重組合找出最優產出，再計算餘弦函數獲得一致性指標。至於效率改善是指前後兩年度的效率比例。
本研究針對以上兩個重要議題收集22個縣市之電量度數、勞工人數、財政支出之三項投入資料以及總體收入、二氧化碳排放之兩項產出資料，利用資料包絡分析方法(DEA)，進行台灣22個縣市的效率分析。針對第一個議題，本研究建構DEA的NT、ST與STT三個模型，將22個縣市分配至增加碳權額度(百分比)vs.意欲產出之成長(百分比)的四個象限。結果指出在NT模型之下，多數農業縣市能獲得大幅的效率提升。在ST模型與STT模型中，台南市，在提升平均總體收入之下，可以增加碳權額度為最多且於市場中進行交易的地區。彰化縣，為在提升平均總體收入之下，可以增加碳權額度為最少且於市場中進行交易的地區。再經由數學規劃的角度，量測碳權交易模型的影子價格。
至於第二個主題，本研究依舊以台灣22個縣市為分析對象，所獲得結果可以形成最優產出一致性vs.效率改善的四個象限。分別為「領導者」、「聚焦最優產出一致性」、「落後者」與「聚焦效率改善」，各個DMU可以按照自己被分派的位置，訂定出未來改善的方向。
;The problem that the construction industry is facing is that the construction quality of engineering projects using traditional construction method is being questioned. Moreover, labor shortage problem is severe. With the development of science and technology and the trend of lower birthrate, the precast concrete method is gradually taking over the cast-in-place method, hoping to solve the labor shortage problem. Furthermore, the precast method can minimize the weather influence and this can help solve the problem of not being able to perform construction due to extreme cold and hot conditions. The precast method can improve the building quality through industrialized means. It adopts a “synchronized engineering strategy” to reach the goal of rapid construction and reduce energy consumption along with noise pollution at the same time. The main engineering project of precast concrete includes tunnel linings, precast concrete curtain walls, stadium stands, structural beams and columns and floor slabs.
The two largest companies in the precast concrete field in Taiwan are Runhorn Pretech Engineering Co., Ltd and Ya Li Precast Prestressed Concrete Industries Corp. The production and operation of a precast concrete company generates “internal cost” and “external cost”. Profit and revenue related to internal cost can be learned from a listed company’s public accounting and financial statements. The accounting and financial statements allow us to learn a company’s operating conditions in a precise sense. As for external cost, it generally means the negative effect and impact caused on society and other private sectors. Electricity is the main energy consumption for factory operation. Greenhouse gas emissions, including nitrogen oxides and carbon dioxide, produced during electricity production are an important factor that causes global warming. Sulfur dioxide is the main cause of acid rain. What’s worse, the particulate matter emitted during electricity power generation is the main root of severe respiratory syndrome. Therefore, in addition to discussing the "internal cost" of a precast concrete plant itself, this study takes the "external cost" of electricity demand generated during the manufacturing process of precast products into consideration. The study shades light on the shadow price estimation of external costs caused by electricity consumption in the concrete plant; moreover, the study discusses the monetization benefit assessment of energy conservation and carbon reduction in the precast engineering process.
Energy conservation and carbon reduction are the trend of economic development all over the world. Under the assignment for regulated quota of carbon rights, we can participate in carbon trading activity regarding spatial regions or temporal interval in order to maximize the level of whole economic development and implement social justice of user charge. However, how to foster interaction between carbon trading and economic growth is the crucial issue. There are 3 carbon trading models involved in this study such as NT model, ST model and STT model. Moreover, the operational situation of DMU’s throughput direction also defined as throughput optimization consistency is taken into consideration. With the efficiency change of Malmquist productivity index (MPI), we can measure DMU’s performance and find out the shortages to make improvement on efficiency. It’s known as “throughput optimization consistency vs. efficiency change”. This study adopts meta-DEA model to figure out marginal productivity and find out optimal throughput under different weights which is assigned. We can use the law of cosine to calculate throughput optimization consistency. Taking a look at efficiency change which is known as efficiency ratio crossing 2 years.
Under the two issues mentioned above, this study is based on 22 counties and cities in Taiwan. We take electricity consumption, labor number and fiscal expenditure as input data. Then, we collect output data of gross income and carbon dioxide. Through data envelopment analysis (DEA), we implement the efficiency analysis of 22 counties and cities in Taiwan. As for the first issue, this study establishes NT model, ST model and STT model, which are regarding DEA model. We can establish four quadrants of “increasing carbon rights (%) vs. benchmarking ratio of increasing desirable output (%)” for 22 counties and cities evaluation. The result shows that lots of agricultural counties and cities can obtain great efficiency improvements through NT model. Taking a look into ST model and STT model, we find that Tainan City acquires the most increasing carbon rights with the increase of the average gross income. Changhua County acquires the lowest increasing carbon rights under the increase of the average gross income. Finally, we use Mathematical Programming to calculate the shadow price of carbon trading models.
In terms of the second issue, this study still takes 22 counties and cities in Taiwan as DMU. We propose the two-dimensional chart divided into 4 quadrants and established by “throughput optimization consistency vs. efficiency change”. The 4 quadrants are divided into "Leader", "Throughput optimization consistency focus", "Laggard" and “Efficiency focus ". All DMUs can formulate improvement on direction when they are assigned to specific position. |
