Input–output analysis is one of the central methodological pillars of industrial ecology. However, the literature that discusses different structures of environmental extensions (EEs), that is, the scope of physical flows and their attribution to sectors in the monetary input–output table (MIOT), remains fragmented. This article investigates the conceptual and empirical implications of applying two different but frequently used designs of EEs, using the case of energy accounting, where one represents energy supply while the other energy use in the economy. We derive both extensions from an official energy supply–use dataset and apply them to the same single‐region input–output (SRIO) model of Austria, thereby isolating the effect that stems from the decision for the extension design. We also crosscheck the SRIO results with energy footprints from the global multi‐regional input–output (GMRIO) dataset EXIOBASE. Our results show that the ranking of footprints of final demand categories (e.g., household and export) is sensitive to the extension design and that product‐level results can vary by several orders of magnitude. The GMRIO‐based comparison further reveals that for a few countries the supply‐extension result can be twice the size of the use‐extension footprint (e.g., Australia and Norway). We propose a graph approach to provide a generalized framework to disclosing the design of EEs. We discuss the conceptual differences between the two extension designs by applying analogies to hybrid life‐cycle assessment and conclude that our findings are relevant for monitoring of energy efficiency and emission reduction targets and corporate footprint accounting.

中文翻译：

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投入产出分析中环境扩展的供给与使用设计：能源案例的概念和经验意义。

投入产出分析是工业生态学的主要方法论支柱之一。但是，讨论环境扩展（EEs）的不同结构（即物质流量的范围及其在货币投入产出表（MIOT）中对部门的归属）的文献仍然是零散的。本文以能源会计为例，研究了应用两种不同但经常使用的电子电气设计的概念和经验意义，其中一种代表能源供应，另一种代表经济使用。我们从官方的能源供应-使用数据集获得这两个扩展，并将它们应用于奥地利的同一单区域输入-输出（SRIO）模型，从而隔离了扩展设计决策所产生的影响。我们还将SRIO结果与全球多区域投入产出（GMRIO）数据集EXIOBASE的能量足迹进行交叉核对。我们的结果表明，最终需求类别（例如，家庭和出口）的足迹排序对扩展设计很敏感，并且产品级别的结果可能相差几个数量级。基于GMRIO的比较进一步表明，对于一些国家，供应扩展的结果可能是使用扩展足迹的两倍（例如，澳大利亚和挪威）。我们提出一种图方法来提供一个通用框架来公开EE的设计。