建築空調系統之節能舉措個案研究： 政策、策略與經濟可行性

Abstract

上市企業公司的 ESG 表現往往與企業的經營績效與綠色發展有著密切相關。隨著全球氣候變遷和能源消耗的增加，環境、社會和管治（ESG）議題在企業和社會中變得越來越重要。在綠色發展的理念下，許多具有前瞻性的企業將ESG具體表現納入企業戰略發展考量。同時，公開企業的ESG報告供社會檢視，以實踐ESG目標，進一步推動企業向綠色發展邁進。商用大樓作為能源消耗的主要來源之一，其空調系統的能源效率對於節約能源至關重要。本研究目標在提出一個基於ESG議題下，商用大樓空調能源改善方案。 以本案園區三棟商業大樓為例，主要根據上市企業的《2022年永續報告(ESG)》，從環境保護、社會責任和企業治理方面研究ESG表現，並得出有利於企業綠色發展的啟示，例如持續推動多項行動方案展現永續經營形象，包括提高韌性以應對公共衛生和極端氣候等環境挑戰。 根據中華民國經濟部能源局的統計，商業辦公大樓的主要耗能設備中，空調佔全年用電量的47.9%，對於辦公室在工作時間的用電造成了巨大負擔。因此，推動商業大樓減少能源消耗並鼓勵企業採用節能空調設備是非常重要的。 本研究除了遵循過去的空調節能改進技術外，還針對建築中央空調系統的過度設計或空調冰水主機的老化效率進行改善。改善措施包括改善老舊空調機的性能或更換為新機，引入節能改進措施到空調系統的節能控制策略，建造或升級建築能源管理系統，以及進行TAB測試、調整和平衡，以優化空調系統的運作。 全球正面臨能源危機，因此節約能源的重要性日益受到重視，特別是在空調系統方面。過去，空調工程完工後的功能驗證常常被忽略，然而這一步驟卻是確保空調系統正常運作和節能計劃成功的關鍵。在功能驗證中，對風管和水管系統進行測試、調整和平衡（TAB）常常需要耗費時間和人力，這使得傳統工程界往往忽略了「省能即省錢」的正確理念（賴明湖，2006）。 另著重在節能改善，以室內空調系統為主要改善對象，透過改善現有建築物的空調冰水側系統，引入業界先進的節能技術和策略，以達到節約能源和減少CO2排放的目標。透過本研究的成果，希望能激勵民間企業跟進，選用符合「一級能效之空調冰水主機」規格，形成更廣泛而良好的示範效果，以推廣綠色發展。 根據台灣經濟部「能源管理法」的相關規定，對於整個專案設備工程的汰換，若使用一級能效設備且能節能10%以上，則可以申請工程總補助金額的30%（單一企業用電100KW以上，補助上限新台幣500萬）。然而，若將空調冰水主機改為二級或三級能效，是否能達到相同的能源效率並值得投資呢？考慮到台灣目前嚴重的缺電情況，若無法立即投資改善空調系統，企業應該採取其他節能措施，如合理調整室內溫度、設置節能照明系統等，以減少能源消耗並推動綠色發展。 最後，從財務角度出發，政府是否應該更積極地鼓勵民間投資更新設備。 各大樓改善前後的節能比率如下：民權大樓為42.11%，AB庫大樓為32.54%，台貨大樓為45.95%，本案總計節能比率為41.02%。設備預期的運轉年限為20年，市場環境的變化可能導致投資項目的IRR折現率出現波動，經濟環境、行業競爭和政府法規等因素的變化，都可能對投資項目的IRR產生影響。投資項目的風險高低也會對IRR折現率產生影響，高風險的投資項目可能要求更高的IRR。此外，資本成本的變動也會對IRR產生影響，若資本成本上升，投資項目的IRR可能會下降。 實施建築空調系統節能措施的經濟可行性是本研究的一個重要方面。本研究評估了實施各種措施所需的前期成本，例如升級替換設備或實施EMS能源控制系統。它還考慮了潛在的節能成本節省，並計算了這些措施的回收期或投資回報。通過分析不同策略的經濟可行性，本研究提供了有關實施建築空調系統節能措施的財務效益和可行性的見解。

The ESG performance of listed companies is often closely related to their business performance and green development. With the increasing global climate change and energy consumption, environmental, social, and governance (ESG) issues have become increasingly important in the corporate and societal context. Under the concept of green development, many forward-thinking companies incorporate ESG performance into their corporate strategic considerations. At the same time, the ESG reports of publicly listed companies are available for public scrutiny, enabling the realization of ESG goals and further promoting green development. Commercial buildings, as one of the main sources of energy consumption, have a critical role in achieving energy savings, particularly in the energy efficiency of their air conditioning systems. This study aims to propose a commercial building air conditioning energy improvement solution based on ESG issues. Taking the three commercial buildings in this case as an example, the ESG performance is studied based on the ESG reports of listed companies in 2022, focusing on environmental protection, social responsibility, and corporate governance. Insights that are beneficial to green development are derived, such as continuously promoting multiple action plans to demonstrate sustainable management practices, including enhancing resilience to address public health and extreme climate challenges. According to statistics from the Energy Bureau of the Ministry of Economic Affairs in Taiwan, air conditioning accounts for 47.9% of the total annual electricity consumption in commercial office buildings, resulting in a significant burden on electricity usage during office hours. Therefore, it is crucial to promote energy consumption reduction in commercial buildings and encourage the adoption of energy-efficient air conditioning equipment. In addition to following past air conditioning energy-saving improvement technologies, this study also focuses on improving the over-designed central air conditioning systems or the aging efficiency of air conditioning chiller units. Improvement measures include enhancing the performance of old air conditioning units or replacing them with new ones, introducing energy-saving control strategies into the air conditioning system, constructing or upgrading building energy management systems, and conducting Testing, Adjusting, and Balancing (TAB) to optimize the operation of the air conditioning system. With the global energy crisis, the importance of energy conservation is increasingly recognized, especially in air conditioning systems. In the past, functional verification after the completion of air conditioning projects was often overlooked, but this step is crucial to ensure the proper operation of the air conditioning system and the success of energy-saving plans. Functional verification, which involves testing, adjusting, and balancing (TAB) the air ducts and water pipes, often requires time and manpower, but it is essential to not overlook the correct concept of "saving energy means saving money" (Lai, M. H., 2006). Furthermore, the study focuses on energy-saving improvements, particularly in indoor air conditioning systems. By improving the air conditioning chilled water systems in existing buildings and introducing advanced energy-saving technologies and strategies, the goal of energy savings and CO2 emissions reduction can be achieved. Through the findings of this study, it is hoped to inspire private enterprises to follow suit and choose air conditioning chiller units that comply with the "Level 1 Energy Efficiency" specifications, thereby creating a broader and positive demonstration effect to promote green development. According to the relevant regulations of the Energy Management Act of the Ministry of Economic Affairs in Taiwan, for the entire equipment engineering project, if Level 1 energy efficiency equipment is used and energy savings of more than 10% are achieved, a subsidy of 30% of the total project cost can be applied for (with a subsidy cap of NTD 5 million for single enterprises with electricity usage of over 100KW). However, if the air conditioning chiller units are changed to Level 2 or Level 3 energy efficiency, can the same energy efficiency be achieved, and is it worth the investment? Considering the severe power shortage situation in Taiwan, if immediate investment in air conditioning system improvement is not possible, companies should adopt other energy-saving measures, such as adjusting indoor temperatures reasonably and installing energy-efficient lighting systems, to reduce energy consumption and promote green development. Lastly, from a financial perspective, should the government actively encourage private investment in equipment upgrades? The energy-saving ratios before and after improvement for each building are as follows: Building A: 42.11%, Building B: 32.54%, Building C: 45.95%. The overall energy-saving ratio for the entire project is 41.02%. The expected operational lifespan of the equipment is 20 years. Changes in market conditions can cause fluctuations in the discounted internal rate of return (IRR) of investment projects. Factors such as economic environment, industry competition, and government regulations can affect the IRR of investment projects. The risk level of the investment project also influences the IRR, with higher-risk projects requiring a higher IRR. Additionally, changes in capital costs can also affect the IRR, with an increase in capital costs potentially leading to a decrease in the IRR of investment projects. The economic feasibility of implementing energy-saving measures for building air conditioning systems is an important aspect of this study. The study evaluates the upfront costs associated with implementing various measures, such as upgrading equipment or implementing EMS energy control systems. It also considers the potential energy cost savings and calculates the payback period or return on investment for these measures. By analyzing the economic viability of different strategies, this study provides insights into the financial benefits and feasibility of implementing energy-saving measures for building air conditioning systems.