Substitution impacts of wood-based textile fibers: Influence of market assumptions

Wood products may help to avoid fossil emissions when they substitute for more fossil-intensive products. However, the estimates of avoided fossil emissions attributed to wood use tend to be based on incomplete market assumptions. Wood products are assumed to fully substitute for non-wood products, yet substitution rarely occurs 1:1 and wood products can also substitute for each other. This study outlines a systematic procedure grounded on economic theory for approximating the existence and rate of substitution between wood and non-wood products, and calculates the marginal avoided fossil emissions with both conventional assumptions and more realistic assumptions based on an expert survey, taking the case of textile markets. The results suggest that regenerated cellulosic fibers (RCFs) are not perfect substitutes for synthetic fibers, meaning that part of an additional RCF supply will replace established textile fibers while part of it merely adds to the overall textile supply, and thereby aggregate fossil emissions. Moreover, in the long term, RCFs are more likely to substitute for synthetics than for cotton, and in the short term, non-viscose RCFs are more likely to substitute for contemporary viscose than for polyester or cotton. In the specified case, the alteration of market assumptions leads to quadrupling the marginal substitution impacts of wood use. Besides the relatively high fossil intensity of contemporary viscose, this is partly explained by increased absolute aggregate fossil emissions. Producing a more realistic account of substitution processes in the forest products markets is central in directing investments that ensure a net reduction in fossil emissions.

Automated summary

Wood products are often assumed to fully substitute non-wood products in order to estimate the avoided fossil emissions. However, this study suggests that substitution rarely occurs on a one-to-one basis, and wood products can also substitute for each other. The study outlines a systematic procedure to approximate the rate of substitution between wood and non-wood products based on economic theory. The results indicate that regenerated cellulosic fibers are not perfect substitutes for synthetic fibers in textile markets, which has implications for the overall fossil emissions.