Dataset: State-of-the-art review of public perceptions and reactions to hydrogen and fuel cell technologies in the European Union

Summary · *Purpose.* Provides the underlying tabulations and secondary analyses used to assess public awareness, attitudes, and acceptance of hydrogen energy and technologies across the EU27, together with a curated state‑of‑the‑art literature mapping. · *What's here.* Aggregated crosstabs by country, gender, and age for key survey items; descriptive statistics; and succinct literature summaries with identifiers. Content is organised as Appendices A–D inside the accompanying supplementary file. · *Status.* This deposit contains derived, publication‑ready tables and figures rather than respondent‑level microdata. Item‑level totals vary because of standard survey routing and missingness. · *Audience.* Researchers in energy transition, policy analysts, and replication reviewers. Contents of this deposit · *Appendix A.* Overview of 30 peer‑reviewed and project sources on European public perceptions of hydrogen with links or DOIs; country coverage summary indicating 24 of the EU27 represented; temporal coverage 2005–2024; and short narrative abstracts for each study. · *Appendix B.* Secondary analysis by gender and age for awareness and opinion items, including distributions and means. · *Appendix C.* Country‑by‑country breakdowns for awareness and four attitudinal items with descriptive patterns. · *Appendix D.* Machine‑readable tables reporting Ns, percentages, and means for awareness and attitudinal items, stratified by gender, age, and country. Geographic and temporal coverage · *Geography.* EU27, with full reporting by member state in the secondary analysis. · *Time window.* Core literature mapping spans 2005–2024. Underlying Gallup fieldwork year is as per the companion article. Measures covered (variable labels) · *A02_4.* Awareness and familiarity with hydrogen as an energy source. · *B07_2.* Views on hydrogen reducing national energy dependence. · *B07_3.* Views on hydrogen as a sustainable energy source. · *B07_5.* Views on hydrogen being as polluting as diesel or gasoline (reverse coded for positive perception). · *B07_6.* Views on the safety of hydrogen compared with other energy sources. · *Demographics.* Gender, age groups, country. File formats and structure · *Primary file.* “Supplementary material for Zenodo_State‑of‑the‑art analysis Hypop_Jensen et al. 2025.docx” containing Appendices A–D. · *Structure.* Appendices are modular: A (literature), B (gender and age distributions), C (country breakdowns), D (tables with Ns, percentages, and means). · *Accessibility.* Tables are laid out for direct extraction to CSV; identifiers embedded in headers. · *No microdata.* Respondent‑level records are not included. Reuse notes · *Intended use.* Comparative snapshots, briefing notes, replication of descriptive figures in the companion article, and policy analytics. · *Citation granularity.* Cite this Zenodo record for any reuse of Appendix D tables or figures derived from them; cite primary studies in Appendix A when drawing on their findings. · *Interoperability.* Variable labels are stable across tables and can be mapped to new codebooks or data dictionaries. Ethics and privacy · *Compliance.* Aggregated reporting only; no personal data or indirect identifiers are present in this deposit. · *Consent and fieldwork.* Ethical oversight and consent procedures follow Gallup standards. Funding and acknowledgements · *Funding.* See the companion article for grant details and project identifiers. · *Acknowledgements.* Appreciation to survey respondents and to the teams whose studies are synthesised in Appendix A. Related works and identifiers · *Companion article.* Jensen et al., 2025 (update with DOI on publication). · *Literature base.* Appendix A lists 30 sources with DOIs or URLs across EU27 contexts (2005–2024). · *Coverage pattern.* Germany most represented in literature mapping; Malta, Cyprus, and Sweden lacked eligible English‑language survey sources. Keywords · hydrogen; public opinion; social acceptance; energy transition; EU27; survey; safety; sustainability; energy dependence; pollution perceptions; cross‑country comparison; replication *Change policy.* Any corrections will be listed here with date stamps; tables will maintain variable labels for backward compatibility.