Modeling challenges for Industry 4.0 implementation in new energy systems towards carbon neutrality: Implications for impact assessment policy and practice in emerging economies

New energy systems (NESs) in a circular economy (CE) perspective may contribute significantly to achieving emerging economies' carbon peaking and neutrality goals. However, CE-based NESs in developing countries towards carbon peaking and neutrality remain unexplored in scientific research and development. Additionally, challenges for I4.0 implementation in the CE context for NESs are still under research gaps in emerging economies. The previous research mainly focused on qualitative discussions on carbon neutrality, I4.0 challenges, and opportunities for renewable energy generation from waste biomass. Therefore, this scientific work, for the first time, offered an innovative decision support model integrating qualitative management tool OGSM (Objective, Goals, Strategies, and Measures), Dombi t-norm and Dombi t-conorm operator based Interval-valued Fermatean fuzzy number (IVFFN) Delphi and IVFFN-Decision Making Trial and Evaluation Laboratory (DEMATE) as a new extension of DEMATEL for assessing interactions among I4.0 implementing challenges in a CE context for NESs towards carbon neutrality which can handle border scale of uncertainty and ambiguity. The findings indicated that out of fifteen I4.0 challenges, nine were identified as causal challenges and the rest as effect group challenges, suggesting that improving causal challenges can notably enhance the effect group challenges. "Lack of aptitude to integrate sophisticated I4.0 infrastructure for NESs" has been identified as the top priority causal challenge that significantly impacts the effect group challenges. Further, based on the findings of IVFFNDEMATEL, short-, mid-, and long-term action plans are proposed for real-time decision-makers to improve the existing situations. The output of the study may contribute robustly to the real-time scenarios of NESs by supporting decision-makers, researchers, government authorities, and stakeholders towards developing sustainable CE-based NESs by integrating I4.0 technologies, which will help to achieve a carbon-neutral economy in emerging economies.