Accounting for effects of carbon flows in LCA of biomass-based products—exploration and evaluation of a selection of existing methods

Abstract

Purpose Life cycle assessment (LCA) has become one of the most widespread environmental assessment tools during the last two decades. However, there are still impacts that are not yet fully integrated, including climate impacts of land use. This study contributes to the development process by testing a selection of recently proposed climate impacts assessment methods, some more focused on the impact of land use and others more focused on a product's carbon life cycle. Methods Several assessment methods have been proposed in recent years, with their development still being in progress. Of these methods, we selected three methods that are more focused on the product's carbon life cycle, and two methods more focused on the impact of land use. We applied the methods to an LCA study comparing biomass-based polyethylene (PE) packaging via different production routes in order to identify their methodological and practical challenges. Results and discussion We found that including the impact of land use and carbon cycles had a profound effect on the results for global warming impact potential. It changed the ranking among the different routes for PE production, sometimes making biomass-based PE worse than the fossil alternative. Especially, the methods accounting for long time lags between carbon emissions and uptake in forestry punished the wood-based routes. Moreover, the variation in the results was considerable, showing that although assessment methods for climate impact can be applied to biomass-based products, their outcomes are not yet robust. Conclusions We recommend efforts to harmonize and reconcile different approaches for the assessment of climate impact of biomass-based products with regard to (1) how they consider time, (2) their applicability to both short and long rotation crops and (3) harmonization of concepts and terms used by the methods. We further recommend that all value laden methodological choices that are built into the methods, such as the choice of reference states/points, are made explicit and that the outcomes of different modelling choices are tested.

Research on Measurement of Regional Differences and Decomposition of Influencing Factors of Carbon Emissions of China’s Logistics Industry

“…Peter et al [6] used the IPCC inventory and modeling methods to calculate the carbon footprint of agricultural products. The research of Liptow et al [7] based on the life cycle theory, used the recently proposed climate impact assessment method to evaluate biological basic products, and discuss carbon emissions during different life cycles. Some scholars used the IPCC method to estimate the total carbon emissions of various provinces in China [8][9][10].…”

Bioenergy carbon emissions footprint considering the biogenic carbon and secondary effects

“…The inclusion of land use and carbon cycle impacts have a profound effect on the results. 51 The impact of biogenic CO 2 and the secondary effect of soil organic carbon/land-use change are excluded in the generalised system boundary reviewed by Patel et al 52 as well as Sunde et al 53 for the woody biomass to liquid production. It should be taken note that the purpose of the table is to highlight the inconsistency rather than to comment on the comprehensiveness of the assessment.…”

“…Similar issue on the biogenic carbon neutrality assumption has been discussed by Wiloso et al 33 The inconsistency is also illustrated through the selected studies in Table 2. Liptow et al 51 identified the same issue as well where the carbon flows in LCA are not fully integrated. The inclusion of land use and carbon cycle impacts have a profound effect on the results 51 .…”

“…Liptow et al 51 identified the same issue as well where the carbon flows in LCA are not fully integrated. The inclusion of land use and carbon cycle impacts have a profound effect on the results 51 . The impact of biogenic CO 2 and the secondary effect of soil organic carbon/land‐use change are excluded in the generalised system boundary reviewed by Patel et al 52 as well as Sunde et al 53 for the woody biomass to liquid production.…”

Environmental Life Cycle Assessment of Grid-Integrated Hybrid Renewable Energy Systems in Northern Nigeria

“…The study focused on three categories or indicators namely the techno-economic, environmental, and social impacts. Liptow et al [10] accounted for the effect of carbon flows in LCA of biomass-based products considering the case of Sweden for wood to ethylene and Brazil for sugarcane to ethylene via different routes. The global warming potentials and land use impacts were the analyzed indicators in the life-cycle.…”