## 2 Methodology for Literature Search and Bibliometric Analysis  
The bibliometric analysis covers the period from 2005 to 2024, selected due to a notable rise in publications on renewable energy strategies for drought mitigation since 2005. This period captures the initial research interest and the recent acceleration in scientific output. Unlike systematic reviews, bibliometric analysis maps the structure of scientific knowledge in a domain. A literature search was conducted using Scopus, chosen for its extensive multidisciplinary coverage, structured indexing, and advanced bibliometric tools that facilitate trend evaluation, keyword co-occurrences, and collaboration networks. Additional references from key journals not indexed in Scopus were manually selected through citation tracking to ensure a comprehensive analysis. Combining data from Scopus with additional references provides a broader perspective, capturing both widely cited works and emerging contributions. This methodological approach enhances the robustness of the findings and ensures accurate reflection of scientific developments in the field. The search terms were carefully structured using Boolean operators to ensure that the selected documents addressed the intersection of renewable energy, extreme drought conditions, and their impact on electrical systems. While an initial search yielded over 500 articles, only 82 met the criteria of simultaneously covering these three thematic areas. This targeted selection highlights the existing research gap in the field. Additionally, some references were added based on citations within the selected documents, further strengthening the analysis. The dataset for this bibliometric analysis was obtained from a single advanced search query in Scopus. The search used Boolean operators (AND, OR, NOT) to structure thematic groups and dependencies between keywords. The full search string used in Scopus was as presented below. TITLE-ABS-KEY ((\"Renewable energy\" OR \"Renewable energies\") AND (\"Drought\" OR \"Water Scarcity\" OR \"Water Resource Management\" OR \"Sustainable Water Management\" OR \"Mega-drought\") AND ((\"Solar\" OR \"Photovoltaic\") OR (\"Wind\")) AND ((\"Green hydrogen\" OR \"Hydrogen\") OR (\"Optimization\" OR \"Improvement\" OR \"Enhancement\" OR \"Maximization\" OR \"Minimization\" OR \"Efficiency\" OR \"Fine-tuning\"))) AND (LIMIT-TO (DOCTYPE, \"ar\") OR LIMIT-TO (DOCTYPE, \"re\") OR LIMIT-TO (DOCTYPE, \"cp\")) AND (EXCLUDE (EXACT KEYWORD, \"Desalination\")). Figure 1 illustrates the logical framework for constructing this search query, showing the theme. Although the study of hydrogen is planned for a later phase, it is included in this review as a forward-looking projection, underscoring the relevance of related articles for future research endeavors [21; 22; 23; 24; 25]. Its inclusion anticipates the potential to enhance  
renewable energy production through hydrogen, providing a preliminary view of future research lines that complement the current objectives. The thematic sets and subsets used in the search include:  
* Renewable Energy (Set): \"Renewable energy\" and \"Renewable energies\";
* Drought (Set): \"Drought\", \"Water Scarcity\", \"Water Resource Management\", \"Sustainable Water Management\" and \"Mega-drought\";
* Photovoltaic Sources (Subset of Non-Conventional Renewable Sources): \"Solar\" and \"Photovoltaic\";
* Wind Sources (Subset of Non-Conventional Renewable Sources): \"Wind\";
* Optimization (Subset of Research Lines): \"Optimization\", \"Improvement\", \"Enhancement\", \"Maximization\", \"Minimization\", \"Efficiency\" and \"Fine-tuning\";
* Hydrogen (Subset of Research Lines): \"Hydrogen\" and \"Green hydrogen\";
* Desalination (Excluded Subset of Research Lines): \"Desalination\" was explicitly excluded from our search query to ensure that the retrieved documents primarily addressed renewable energy strategies rather than water treatment technologies. However, the exclusion applied only to articles where \"Desalination\" was a significant keyword or thematic focus.