過去台灣的既有建築物興建時尚無節能減碳之觀念，未能管制建築外殼隔熱及遮陽性能，加上空調超量設計，老舊設備性能不佳等因素，造就出建築耗能大量浪費。本研究回顧過去自2002年起至2012年間，政府因應中央機關及國立大院校的一系列綠建築更新改造計劃中，如「綠廳舍改善計畫」、「綠建築更新診斷與改造計畫」、「綠空調改善計畫」及「建築能源效率提升計畫」所完成之案例，針對其建築外殼性能、照明系統及空調系統更新改善之手法，進行節能效益及生命週期成本等經濟效益之評估。

本研究採用「生命週期成本評估」及「工程經濟學」之研究方法進行既有建築物節能改善及經濟效益分析。首先透過標準化各類型建築物的營運條件、統一台灣貨幣利率條件及電費標準，進而消除不同節能手法及案例間之計算差異。接著，透過可靠的建築能源模擬軟體(eQUEST)分析其動態能耗，以彌補部份節能效益無法用線性關係計算而得知的節能改善手法，如空調節能改善、建築外殼更新等。最後，在進行改善工程成本估算時，採用具統一標準的公共工程預算成本估價原則，估算出該節能改善工程之生命週期成本及回收年限。

藉由上述方法發現公有廳舍節能改善手法中，總節能潛力及經濟效益依序為(1).空調系統節能改善、(2).室內照明系統節能改善、(3).建築外殼節能改善。其中，空調系統節能改善可減少10.6%的總建築耗能，平均生命週期回收年限為3~5年；而室內照明系統節能改善案例中，平均總建築節能率及生命週期回收年限分別為4.4%及4~6年；建築外殼節能改善手法中，經濟效益最佳者為改善高日射量方位(南向、西向)的遮陽設計，建築總節能率為4.02%，其生命週期成本約可於7~12年內回收。

以上結果顯示，在台灣目前利率及電費飆漲的趨勢下，建築節能改善仍具有高度經濟誘因，應即早開始執行舊建築物之節能改善，但持續落實對新建建築物的節能設計把關，才是真正杜絕不必要建築能源浪費的解決之道。

In the past, Taiwan's existing building designs lacked the energy saving concepts and fail to regulate building envelope insulation and shading performance. The inefficient and poorly designed AC and equipment systems often lead to a huge waste of energy. This study presents the potential energy saving and Cost-Effectiveness of the building envelope, lighting and AC systems retrofit in Taiwan’s public buildings since 2002 till 2012, including “Green Remodeling Program for Governmental Buildings”, “Green Building Diagnosis and Renew plan”, “Green Air Conditioning Improvement Program” and “Building Energy Efficiency Upgrade Program(BEEUP)”.

This study adopt Life Cycle Cost (LCC) and Engineering Economics Assessments to analyze the energy saving and economic efficiency of existing building retrofit. Firstly, by unified building operating condition, interest rate scenarios and tariff standards to eliminate the differences between various retrofit methods and projects. Subsequently, this study conducted building energy simulation (eQUEST) to calculate the dynamic AC systems energy consumption which can not be evaluated using a linear equation, such as AC systems and building envelope retrofit. Finally, using Public Construction Cost Estimating Standard to estimate the construction costs, total life cycle cost and payback period.

Through the above analysis, the order of the energy saving and Cost-Effectiveness of Taiwan’s public building systems retrofit is: (1) AC systems energy efficiency improvement, (2) Indoor lighting system retrofit, (3). Building envelope insulation and shading retrofit. The AC systems energy efficiency improvement can reduces 10.6% of the total building energy consumption, with an average LCC payback period of 3~5 years, while the average building energy-saving ratio and LCC payback period of indoor lighting systems are 4.4% and 4~6 years, respectively. The most economical building envelope retrofit method is to improve the shading performance of high solar radiation orientation (south, west), the average building energy-saving ratio is 4.02% and the LCC can be recovered in about 7~12 years.

The results indicate that with the Taiwan’s current trend of interest rate and tariff standards, existing buildings retrofit still are highly economical which should begin immediately. However, continuing to reinforce the energy-saving regulations for new buildings design is the true solution to prevent unnecessary waste of building energy.

中文部份：
(1)台灣建築物CO2排放量簡易評估法之研究，張又升、鄭元良、林憲德、許茂雄，建築學報（TSCI）第41期，中華民國建築學會，2002
(2)綠色建築/生態.節能.減廢.健康，林憲德，詹氏書局，2006
(3)辦公建築全年空調耗能量簡易預測法之研究，黃國倉、林憲德，建築學報（TSSCI），第58期，第131-148頁，2006
(4)綠建築推動方案，內政部，2003
(5)既有建築綠建築改善參考手冊之研究，內政部建築研究所委託研究報告，2005
(6)綠建築解說與評估手冊(2009年版)，林憲德，內政部建築研究所，2009
(7)綠建築評估手冊 - 基本型(2011年版)，林憲德，內政部建築研究所，2011
(8)建築物能源管理及效率指標研究計劃，財團法人台灣建築中心，經濟部能源局，2005
(9)綠建築更新診斷與改造計畫，財團法人台灣建築中心，內政部建築研究所，2008
(10)綠建築更新診斷與改造計畫，財團法人台灣建築中心，內政部建築研究所，2009
(11)綠建築更新診斷與改造計畫，財團法人台灣建築中心，內政部建築研究所，2010
(12)綠建築更新診斷與改造計畫，財團法人台灣建築中心，內政部建築研究所，2011
(13)綠建築更新診斷與改造計畫，財團法人台灣建築中心，內政部建築研究所，2012
(14)建築能源效率提升計畫，財團法人台灣建築中心，內政部建築研究所，2008
(15)建築能源效率提升計畫，財團法人台灣建築中心，內政部建築研究所，2009
(16)建築能源效率提升計畫，財團法人台灣建築中心，內政部建築研究所，2010
(17)建築能源效率提升計畫，財團法人台灣建築中心，內政部建築研究所，2011
(18)建築物耗能評估軟體驗證之研究–既有建築節能改善之效益評估，內政部建築研究所協同研究報告，2012
(19)既有建築物節能改善技術之研究，內政部建築研究所委託研究報告，2012
(20)大學校園建築節能措施成本效益與推行阻礙之研究-以國立台灣大學為例，周祐康，臺灣大學土木工程學研究所學位論文，2012
(21)老舊建築物外牆劣化整建更新工法之應用研究，郭斯傑,、黎昌憲、李育陞，建築學報，pp. 25-44， 2012
(22)以生命週期成本觀點研析學生宿舍建築之維護成本與策略，羅紫萍、羅昱盈、郭斯傑，建築學報, pp. 1-18, 2010
(23)工程經濟學觀點分析舊建築物外遮陽改善節能之經濟效益探討，陳天能，逢甲大學土木工程所碩士論文，2012
(24)綠建築日常節能指標改善校園舊有建築耗能之研究-以中華大學建築與規劃學院為例，陳紀宏，中華大學營建管理學系碩士碩士論文，2012
(25)既有辦公大樓空調系統節能對策研擬及效益分析，黃慶福，國立勤益科技大學冷凍空調系碩士論文，2010
(26)照明設備成本及性能對節能效益影響之研究，吳培旭，國立臺灣科技大學電機工程系碩士論文，2009
(27)大專院校舊有建築物耗能之研究---以綠建築日常節能指標評估改善照明系統節能效率，葉武宗，國立交通大學工學院工程技術與管理學程碩士論文，2006
(28)建築節能設計經濟效益評估-外殼、晝光、照明、空調之綜合評估，陳聖仙，國立成功大學建築系碩士論文，1995
(29)舊有辦公建築物節能改善之效益分析，黃瑞欽，國立臺北科技大學冷凍空調工程系所碩士論文，2005
(30)辦公建築空調系統之生命週期經濟效益分析研究—以地方政府廳舍冰水主機房汰舊換新為例，詹邦鎮，國立台北科技大學建築與都市設計研究所碩士論文，2008
(31)設備維護管理與生命週期成本之探討-探討各種維護策略，陳良進，工學院工程管理碩士在職專班碩士論文，2010
(32)具有中央空調之教學大樓耗能解析與節能潛力研究，鄭正仁，國立臺北科技大學冷凍空調工程系所碩士論文，2006

外文部份：
(1).LEED - LEED for Existing Buildings: Operations & Maintenance，2009
(2).ASHREA - ASHREA Standard 90.1，2007
(3).ENERGY STAR® - Performance Ratings Technical Methodology，2006
(4).CASBEE建築環境総合性能評価システム - CASBEE-既存評估手冊，建築環境省エネルギー機構，國土交通省住宅局，2008
(5).CASBEE建築環境総合性能評価システム - CASBEE-改修評估手冊，建築環境省エネルギー機構，國土交通省住宅局，2008
(6).BREEAM - The Environmental Rating for Existing Housing Guidance，2006
(7).C. Y. Chang and H. T. Lin, "Energy saving and payback period for retrofitting of lighting systems in Taiwan," Applied Mechanics and Materials, vol. 71-78, pp. 2190-2195, 2011.
(8).C. Y. Chang, H. T. Lin, C. T. Tzeng, K. H. Yang, Y. K. Chuah, and M. C. Ho, "Energy saving and payback period for retrofitting of air conditioning systems in Taiwan," Applied Mechanics and Materials, vol. 121-126, pp. 2850-2854, 2012.
(9).N. Aste and C. Del Pero, "Energy retrofit of commercial buildings: case study and applied methodology," Energy Efficiency, pp. 1-17, 2012.
(10).İ. Çakmanus, "Renovation of existing office buildings in regard to energy economy: An example from Ankara, Turkey," Building and Environment, vol. 42, pp. 1348-1357, 2007.
(11).S. E. Chidiac, E. J. C. Catania, E. Morofsky, and S. Foo, "Effectiveness of single and multiple energy retrofit measures on the energy consumption of office buildings," Energy, vol. 36, pp.5037-5052, 2011.
(12).R. Galvin and M. Sunikka-Blank, "Including fuel price elasticity of demand in net present value and payback time calculations of thermal retrofits: Case study of German dwellings," Energy and Buildings, vol. 50, pp. 219-228, 2012.
(13).Y. Huang, J.-l. Niu, and T.-m. Chung, "Energy and carbon emission payback analysis for energy-efficient retrofitting in buildings—Overhang shading option," Energy and Buildings, vol. 44, pp. 94-103, 2012.
(14).G. Kumbaroğlu and R. Madlener, "Evaluation of economically optimal retrofit investment options for energy savings in buildings," Energy and Buildings, vol. 49, pp. 327-334, 2012.
(15).R. Misra, T. K. Aseri, D. K. Jamuwa, and V. Bansal, "Assessment of CO2 emission reduction and identification of CDM potential in a township," Energy Efficiency, vol. 5, pp. 471-481, 2012.
(16).Y. Nikolaidis, P. A. Pilavachi, and A. Chletsis, "Economic evaluation of energy saving measures in a common type of Greek building," Applied Energy, vol. 86, pp. 2550-2559, 2009.
(17).A. M. Papadopoulos, T. G. Theodosiou, and K. D. Karatzas, "Feasibility of energy saving renovation measures in urban buildings: The impact of energy prices and the acceptable pay back time criterion," Energy and Buildings, vol. 34, pp. 455-466, 2002.
(18).B. Rismanchi, R. Saidur, H. H. Masjuki, and T. M. I. Mahlia, "Energetic, economic and environmental benefits of utilizing the ice thermal storage systems for office building applications," Energy and Buildings, vol. 50, pp. 347-354, 2012.
(19).H. Tommerup and S. Svendsen, "Energy savings in Danish residential building stock," Energy and Buildings, vol. 38, pp. 618-626, 2006.
(20).G. Verbeeck and H. Hens, "Energy savings in retrofitted dwellings: economically viable?," Energy and Buildings, vol. 37, pp. 747-754, 2005.
(21).W. Wang, J. Zhang, D. Moser, G. Liu, R. Athalye, and B. Liu, "Energy and Cost Savings of Retro-Commissioning and Retrofit Measures for Large Office Buildings," Pacific Northwest National Laboratory (PNNL), Richland, WA (US)2012.
(22).M. Boubekri, "Life cycle cost analysis of building re-lamping alternatives," Journal of Renewable and Sustainable Energy, vol. 4, p. 023119, 2012.
(23).M.-C. Dubois and Å. Blomsterberg, "Energy saving potential and strategies for electric lighting in future North European, low energy office buildings: A literature review," Energy and Buildings, vol. 43, pp. 2572-2582, 2011.
(24).T. M. I. Mahlia, H. A. Razak, and M. A. Nursahida, "Life cycle cost analysis and payback period of lighting retrofit at the University of Malaya," Renewable and Sustainable Energy Reviews, vol. 15, pp. 1125-1132, 2011.
(25).T. M. I. Mahlia, M. F. M. Said, H. H. Masjuki, and M. R. Tamjis, "Cost-benefit analysis and emission reduction of lighting retrofits in residential sector," Energy and Buildings, vol. 37, pp. 573-578, 2005.
(26).F. Salata, A. de Lieto Vollaro, and A. Ferraro, "An economic perspective on the reliability of lighting systems in building with highly efficient energy: A case study," Energy Conversion and Management, vol. 84, pp. 623-632, 2014.