From Proof-of-Work to Proof-of-Stake: a comparative study on sustainability, scalability and governance in blockchain networks

Purpose The purpose of this study is to comparatively examine how different blockchain consensus mechanisms – Proof-of-Work (PoW) and Proof-of-Stake (PoS), including the transition from PoW to PoS – shape sustainability, scalability and governance outcomes in enterprise-relevant blockchain networks. By analysing Bitcoin, Ethereum and Cardano using a mixed-methods design, the study moves beyond single-metric evaluations and provides an integrated socio-technical assessment of consensus architecture. In doing so, it contributes to theory, practice and policy by clarifying how consensus design choices influence the development of sustainable and resilient blockchain infrastructures. Design/methodology/approach This study adopts a mixed-methods, documentary comparative research design. It analyses Bitcoin (Proof-of-Work) and Ethereum (PoW-to-PoS transition) as primary empirical cases using secondary quantitative indicators (energy consumption, transaction throughput and finality) and qualitative document analysis of protocol and governance materials. Sustainability, scalability and governance are employed as analytical lenses to guide cross-case comparison. Qualitative data are examined through structured thematic coding to contextualise quantitative trends. Findings The findings indicate that Proof-of-Stake delivers substantial sustainability and scalability advantages over Proof-of-Work. Ethereum's transition to PoS resulted in a reduction in energy consumption of over 99%, while enabling gradual improvements in transaction throughput and settlement finality relative to Bitcoin's static baseline. However, these performance gains are accompanied by governance trade-offs, including risks of validator concentration and delegator passivity. The analysis suggests that although PoS improves environmental and operational efficiency, its long-term effectiveness depends on governance mechanisms capable of preserving decentralisation and accountability. Research limitations/implications First, it relies primarily on secondary data and documentary sources, which may not fully capture real-time network dynamics or evolving governance practices. Second, the comparative analysis focuses on a limited set of major blockchain networks – Bitcoin, Ethereum and Cardano – which constrains the generalisability of the findings to other platforms with different consensus architectures. Despite these limitations, the study provides important implications for researchers, practitioners and policymakers by highlighting the central role of consensus design in shaping sustainability, scalability and governance outcomes. Future research could extend this framework to additional blockchain platforms, incorporate primary stakeholder interviews and employ real-time network telemetry to refine performance and energy-consumption assessments. Practical implications The findings offer actionable guidance for blockchain developers, enterprises and policymakers. Developers should prioritise energy-efficient consensus designs and implement governance mechanisms that mitigate validator concentration. Enterprises seeking scalable and sustainable blockchain solutions may benefit from PoS-based networks that offer lower operational costs and faster transaction finality. For policymakers, the results highlight the importance of regulatory frameworks that incentivise energy-efficient blockchain infrastructures while safeguarding decentralisation, transparency and open participation across staking and governance systems. Social implications The transition from energy-intensive Proof-of-Work to Proof-of-Stake consensus mechanisms has broader social implications for trust, participation and digital inclusion in blockchain ecosystems. Reduced energy consumption addresses public concerns around environmental harm and social legitimacy of blockchain technologies. However, PoS systems may introduce participation inequalities if staking requirements favour wealthier actors. These findings highlight the importance of inclusive governance designs that promote broad validator participation, transparency and accountability, ensuring that sustainability gains do not come at the expense of decentralisation or equitable access to blockchain-based infrastructures. Originality/value This study provides an original comparative assessment of blockchain consensus mechanisms by integrating sustainability, scalability and governance within a single analytical framework. Unlike prior research that often examines energy efficiency or performance in isolation, the study combines quantitative benchmarking with qualitative governance analysis to reveal the socio-technical trade-offs associated with Proof-of-Stake adoption. By analysing a PoW-to-PoS transition alongside a mature PoW system and drawing on PoS-native platforms in the literature as comparative reference points, the article offers new insights into how consensus design choices shape the long-term viability of enterprise-relevant blockchain networks.