Evaluating eco-innovation efficiency and club convergence trends across the European Union: A window slack-based measure approach

This study assesses the eco-innovation efficiency of 27 European Union member states from 2016 to 2023, using a Window Slack-Based Measure Data Envelopment Analysis model and club convergence analysis across five dimensions: finance and support, firm investments, intellectual assets, sales impacts, and environmental sustainability. The results reveal significant fluctuations, with short-term gains during the pandemic followed by declines linked to geopolitical shocks. Convergence analysis identifies two distinct groups of countries: one characterized by stronger use of public funding, innovation investment, and environmental productivity, and another facing persistent challenges in funding efficiency and environmental impact mitigation. To address these disparities, high-performing countries should prioritize patent development and export diversification, while lower-performing countries would benefit from stricter environmental regulation and more outcome-driven research and development funding. Promoting cross-group collaboration, through joint research and development initiatives, knowledge-sharing platforms, and eco-innovation trade agreements, supported by European Union frameworks like Horizon Europe, could help bridge performance gaps.