R Buitrago-Tello et al.
Original Article: Linerboard production and decarbonization
Sensitivity analysis for the cost of avoided carbon Sensitivity analysis for the cost A sensitivity analysis was conducted to identify the variables influencing the CAC by varying the costs of electricity, natural gas, chemicals, and capital investment by ±25% for each alternative, excluding revenue from carbon offsets. Figure 6 shows the change in the CAC for emissions Scope 1 and Scope 2 under this analysis. For energy efficiency improvements in the paper machine, the primary variable affecting the CAC for the nylon felt and the shoe press was the natural gas price, with variations of ±25% and ±63%, respectively. In contrast, the CAC for the condebelt technology varied by ±65% with changes in capital investment and ±40% with natural gas price fluctuations. The condebelt option involved a higher capital investment compared to the nylon felt and shoe press. Regarding technologies for concentrating black liquor, the MVR system shows a CAC variation of ±158% with natural gas price changes, driven by significant savings in the natural gas boiler, ±81% with capital investment, and ±52% with electricity costs. On the other hand, the membrane system’s most critical factor was membrane cost, with variations of ±19% for the four-membrane system and±17.5% for the five-membrane system. These variations were higher than the CAC variation associated with total capital investment, which were ±17% for the four-membrane system and±15% for the
five-membrane system, indicating that reducing membrane costs was essential to improve the system’s cost effectiveness. In the case of the high-efficiency recovery boiler, capital investment was the most significant variable affecting the CAC. This alternative had the highest capital investment with limited revenue from the operating cost savings or, in this case, the electricity surplus. For example, the revenue from electricity surplus was comparable with the natural gas savings achieved with MVR and condebelt technologies, which had lower carbon-emission reductions. Sensitivity analysis for carbon emissions from the electricity demanded The CAC was also determined using the emissions factors reported by the US Energy Information Administration for two scenarios that assumed the introduction of renewable energies in the electric system under two conditions: (i) high cost for renewable energies: no cost reductions in renewable technologies, and (ii) low cost for renewable energies: renewables achieve 40% lower overnight capital costs by 2050. 24,25 The emission factors for these scenarios, which evolve over time, are detailed in Supporting Information, Table S12. The low-cost scenario consistently resulted in lower emission factors. For instance, in 2021, the emission factor was 0.392 kg CO 2 /kWh for both scenarios. By 2050, it will decrease to 0.263 kg CO 2 /kWh in the high-cost scenario and to 0.178 kg CO 2 /kWh in the low-cost scenario.
Figure 7. Carbon reductions for linerboard production under a scenario with higher participation of renewable energy in the power generation system. Scenario: High cost for renewable energy.
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© 2025 The Author(s). Biofuels, Bioproducts and Biorefining published by Society of Industrial Chemistry and John Wiley & Sons Ltd. | Biofuels, Bioprod. Bioref . (2025); DOI: 10.1002/bbb.2790
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