Fig. 3: Comparison of electric energy consumption and CO₂ emissions in CF production from aqPAM and conventional PAN precursor fibres.

a Electric energy consumption-relative index during the production of PAN-CFs⁶ and aqPAM-CFs from the precursor fibres. b CO₂ emissions-relative index during the production of PAN-CFs¹⁴ and aqPAM-CFs from the precursor fibres. The difference in the corresponding electric energies of stabilisation between aqPAM fibres and PAN fibres was estimated from the experimental results when our laboratory-sized furnace was used at these temperature conditions (Supplementary Tables 12 and 13). In this study, the energy consumption in the stabilisation operation is solely in the form of electricity. Note that reduced energy consumption and CO₂ emissions during high-yield polymerisation and dry spinning without organic solvent for producing aqPAM fibres (with estimated reduction rates of ≥50% for both, compared with producing PAN fibres, as shown in Supplementary Table 3) are not considered here. However, these reductions are expected to lead to further reduction in CO₂ emissions for the entire CF production process, potentially by ≥40%.