income collected in different surveys, such as statistical matching. For the application in Bulgaria and the related performance evaluation, see Rude and Robayo-Abril (2024).

**Moreover, Bulgaria would benefit from improving the data environment around measuring energy poverty based on three factors** . First, greater granularity, both geographically speaking and concerning the frequency of data collection, could help with local implementation approaches and tracking of energy poverty over time. Next, harmonizing datasets across countries could facilitate the comparison of energy poverty rates across countries and identify those most in need at the European level. Third, close collaborations between academia, research institutions, analysts, and the government could create valuable knowledge and innovative approaches in this area, especially using big data sources.

**The measurement of the definition of energy poverty and the development of all energy poverty policies should be based on meaningful and transparent processes of public involvement and inclusive engagement with various stakeholders** . Establishing a common understanding of what energy poverty entails and how it is measured helps ensure that different stakeholders, including policymakers, researchers, and communities, are on the same page. This shared understanding forms the foundation for policies aiming to reduce energy poverty. Given the multidimensional nature of the issue, appropriate coordination and involvement of relevant stakeholders in energy poverty reduction efforts is critical, including national statistical offices, finance ministries, sectoral ministries, and other significant entities (at local and national levels). A broad consultation process can improve the acceptance of a methodological approach, including consensus on the minimum comfort levels.

**Finally, energy poverty observatories are also invaluable tools for addressing and combatting energy poverty; in the EU, several countries have established country-specific energy poverty observatories.** Well-designed energy poverty observatories work as a platform that unites practitioners, decisionmakers, and researchers addressing energy poverty in the country and beyond. The growing importance of evidence-based energy poverty policy-making at the European Union (EU) level underscores the necessity for establishing a dedicated decision-support hub in Bulgaria. As an EU Member State with some of Europe's highest energy poverty rates, Bulgaria faces pronounced structural challenges at the intersection of energy, low incomes, and poor housing.

**The Energy Poverty Observatory can help comprehensively tackle these issues.** First, it provides a means to accurately quantify the current levels of energy poverty within a region or country. This quantification is vital for understanding the extent of the issue, identifying the affected population, and enabling targeted interventions. In the Bulgarian context, the observatory can help develop a rigorous and comprehensive set of indicators to operationalize the new legal energy poverty definition and create a central repository of these indicators. Second, the observatory can facilitate ongoing monitoring of energy poverty trends and developments. This longitudinal or temporal analysis helps assess the effectiveness of implemented policies and interventions, guiding adjustments or improvements where necessary. Third, it can be crucial to identify the multifaceted factors contributing to energy poverty and develop evidence-based policy recommendations. Lastly, it plays a crucial role in convening key stakeholders to understand energy poverty comprehensively across different sectors and levels<sup>48</sup> . By pinpointing these factors, policymakers and stakeholders can tailor strategies to mitigate the root causes and alleviate the burden of energy poverty on vulnerable

> 48 This involves a broad spectrum of national and local decision-makers, encompassing the energy regulator, the Ministry of Labour and Social Policy, the Social Protection Agency, the Ministry of Health, Ministry of Regional Development and Public Works, the Ministry of Energy, the Sustainable Energy Development Agency, local authorities, the statistical office, and the Energy and Water Regulatory Commission (EWRC). Additionally, it includes practitioners from the energy, housing, and social sectors, advocacy groups, the media, other EU observatories, development support agencies, the private sector, and the research community.

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