A comparative multi-criteria decision analysis framework for strategic energy storage investments: From data to decisions

Energy storage is increasingly recognised as a critical enabler of Europe’s clean energy transition, yet Member States display heterogeneous levels of readiness to integrate and scale storage solutions. This study introduces the Investment Planning Tool, a multi-criteria, interactive decision-support framework designed to evaluate alternatives under diverse uncertainty levels, weighting schemes, and behavioural profiles. By integrating classical and extended MCDA approaches within a unified architecture, the IPT enables comprehensive and flexible assessments for strategic planning. To demonstrate its applicability, the framework is adapted into a comparative readiness assessment of 13 EU Member States, evaluated against nine socio-economic, political-regulatory, technological, and infrastructural criteria that shape the energy storage environment. The results reveal significant differentiation across countries: Portugal, Austria, and Slovenia consistently emerge as top performers, reflecting mature regulatory frameworks, strong institutional capacity, and supportive policy environments, while Belgium and Luxembourg show persistent structural and regulatory deficiencies. Sensitivity analyses across multiple methodological configurations demonstrate different levels of robustness across the methods, highlighting the implications of selecting between alternative decision profiles. While the Investment Planning Tool provides a transparent and scalable platform, key limitations include reliance on a restricted indicator set and potential biases in expert-derived weights. Nonetheless, the framework offers substantial policy value, enabling the identification of critical readiness gaps, informing targeted interventions, and supporting evidence-based planning in alignment with EU decarbonisation objectives.