The commercialization of sodium-ion batteries (SIBs) is around the corner to support on electrification of various applications, especially focused on light electromobility and stationary applications. The anode of choice in SIBs is hard carbon (HC) following the success story of graphite anode in lithium-ion batteries. ^[1-4] One of the greatest advantages of HC is that the bio-waste precursor can be used, enhancing sustainability and provides cheap material price from its abundance. However, bio-waste HC often undergoes a strong acidic/basic pre-/post-treatment for removing impurities and increasing carbon yield but decreases initial Coulombic efficiency (ICE) and total sodium uptake in turn. ^[5,6] We attempted to find a more sustainable solvent to replace the traditional method for such HCs. In this work, the morphology, microstructure, and electrochemical performance characteristics of hazelnut shells-derived HCs were investigated when processed in different pre-treatment agents (i.e., no pre-treatment, acid treatment, and water washing). ^[7] The results reveal that hazelnut shell derived-HCs produced via facile and sustainable water washing outperform those obtained via other processing methods in terms of ICE, capacity uptake and retention. Moreover, the applicability of the hazelnut shell-derived HC is demonstrated in a sodium-ion full-cell. Finally, the cost-ecological effectiveness of sustainably processed HC compared to acid processed one was investigated and confirmed by life cycle assessment (LCA) and cost analysis. [1] CATL, “CATL Unveils Its Latest Breakthrough Technology by Releasing Its First Generation of Sodium-ion Batteries,” 2021. [2] L. Cailloce, https://newscnrsfr/articles/a-battery-revolution-in-motion 2015. [3] S. Kuze, J. Kageura, S. Matsimoto, T. Nakayama, M. Makidera, M. Saka, T. Yamaguchi, T. Yamamoto, K. Nakane, R&D Report 2013, 1–13. [4] A. Rudola, A. J. R. Rennie, R. Heap, S. S. Meysami, A. Lowbridge, F. Mazzali, R. Sayers, C. J. Wright, J. Barker, Journal of Materials Chemistry A 2021, 9, 8279–8302. [5] S. Ghosh, R. Santhosh, S. Jeniffer, V. Raghavan, G. Jacob, K. Nanaji, P. Kollu, S. K. Jeong, A. N. Grace, Sci. Rep. 2019, 9, 16315. [6] K. L. Hong, L. Qie, R. Zeng, Z. Q. Yi, W. Zhang, D. Wang, W. Yin, C. Wu, Q. J. Fan, W. X. Zhang, Y. H. Huang, Journal of Materials Chemistry A 2014, 2, 12733–12738. [7] H. Moon, A. Innocenti, H. Liu, H. Zhang, M. Weil, M. Zarrabeitia, S. Passerini, ChemSusChem 2022 DOI: 10.1002/cssc.202201713