重塑永續產品設計思維： 以多目標最佳化及生命週期評估打造永續產品設計方法學

Abstract

永續產品設計已成為解決產品於製造與消費過程中環境、經濟及社會挑戰的關鍵策略，旨在創造滿足當代需求而不損及後代需求滿足能力的產品。然而，現行永續設計方法常難以在整個產品生命週期中平衡多重目標，忽略關鍵階段（特別是使用階段），且因實用性不足而缺乏廣泛產業接受度。為解決這些問題，本研究開發了一套創新的四步驟永續產品生命週期管理方法，運用多目標生命週期最佳化。方法學包含四大步驟：(1)辨識潛在設計路徑；(2)評估永續性表現；(3)建構最佳化模型；(4)透過加權總和法求解，建立最佳設計方案的帕雷托前緣。案例分析結果顯示，此方法能在維持經濟可行性的同時，大幅降低各類產品的環境影響。案例分析將方法學應用於臺灣手搖杯，相較於基準情境，應用本研究方法的手搖杯設計，展現出全球暖化潛勢最多可降低60%、毒性指標可降低80%的潛力，同時兼顧經濟表現。研究結果揭示不同永續目標間的複雜權衡關係，強調在產品設計中考量多重生命週期的重要性，實現對不同材料、製程與終端處置情境的全面評估。本研究為產業提升產品永續性及推動潔淨生產提供實用框架，可作為各產業發展更精緻永續產品設計模式的起點，並具有納入社會影響評估及應用至其他產品類別的拓展潛力。此外，亦為永續設計決策提供量化基礎，對政策制定與產業永續倡議具有參考價值，有望改變產品設計與製造方式，促進產業永續轉型。

Sustainable product design has emerged as a critical approach to address environmental, economic, and social challenges in manufacturing and consumption, aiming to create products that fulfill present needs without compromising future generations' ability to meet their own. Current sustainable design approaches often struggled to balance multiple objectives across entire product lifecycles, overlooking key phases, particularly usage, and lacking widespread industry acceptance due to limited practicality. To address these gaps, we developed a novel four-step methodology for sustainable product lifecycle management using multi-objective life cycle optimization. Here we show that this approach can significantly reduce environmental impacts while maintaining economic viability across various product categories. Our methodology, which involves (1) identifying potential design pathways, (2) assessing their sustainability, (3) formulating an optimization model, and (4) solving it using a weighted sum method, generated a Pareto frontier of optimal design solutions. Applying this to a case study in Taiwan's boba tea packaging industry, we demonstrated potential reductions of up to 60% in Global Warming Potential and 80% in toxicity measures compared to baseline scenarios, while considering economic performance. Our results reveal the complex trade-offs between different sustainability objectives and highlight the importance of considering multiple lifecycles in product design, enabling a comprehensive evaluation of various options including different materials, manufacturing processes, and end-of-life scenarios. This study provides a practical framework for industries to enhance product sustainability, promoting cleaner production practices. We anticipate our approach to be a starting point for more sophisticated models of sustainable product design across various sectors, with potential expansion to include social impacts and application to other product categories. Moreover, it offers a quantitative basis for sustainable design decisions, relevant for policy development and industry-wide sustainability initiatives, potentially transforming how products are designed and manufactured for a more sustainable future.