In our built environment, flat glass is an indispensable material. Its production requires the mining of raw materials and the use of fossil fuels and results in the emission of pollutants including CO₂. In Western European countries, these emissions have been the target of a series of energy efficiency measures and emission reduction policies since 1945. Beginning with that year, this article studies the material history of the flat glass industry in Belgium, France and the EU and analyses the evolution of the flows of materials, energy and CO₂ related to the manufacturing process. Based on a retrospective material and energy flow analysis (MEFA), the objective is to assess the environmental footprint of the architectural flat glass sector and to provide an understanding of the socioecological patterns that have shaped its metabolism.

Based on an extensive data collection, this paper is the first publication of long-term time series on the manufacturing of architectural glass. The findings reveal two major concerns: on the one hand, energy efficiency measures have weakened ever since the 1990s, despite the tightening of the European environmental policies; on the other hand, the demand for architectural glass in the EU remains particularly high, resulting in a production rate that uses considerable energy and exploits a large amount of raw materials. The relative decoupling of the energy and CO₂ intensities seems to have reached a threshold and has not resulted in an absolute decoupling of environmental burdens from industrial growth. We discuss measures and research needs to support a decarbonisation of the flat glass sector.

在我们的建筑环境中，平板玻璃是不可或缺的材料。其生产需要开采原材料和使用化石燃料，并导致排放包括CO ₂在内的污染物。在西欧国家，这些排放量自 1945 年以来一直是一系列能效措施和减排政策的目标。从那一年开始，本文研究了比利时、法国和欧盟平板玻璃行业的物质历史，并进行了分析。材料、能量和 CO ₂流动的演变与制造工艺有关。基于回顾性材料和能量流分析 (MEFA)，目标是评估建筑平板玻璃行业的环境足迹，并了解塑造其新陈代谢的社会生态模式。

基于广泛的数据收集，本文首次发表了建筑玻璃制造的长期时间序列。调查结果揭示了两个主要问题：一方面，尽管欧洲环境政策收紧，但能效措施自 1990 年代以来一直在减弱；另一方面，欧盟对建筑玻璃的需求仍然特别高，导致生产速度消耗大量能源并开发大量原材料。能源和 CO ₂强度的相对脱钩似乎已达到阈值，并没有导致环境负担与工业增长的绝对脱钩。我们讨论了支持平板玻璃行业脱碳的措施和研究需求。