Grid extension vs. off-grid systems in rural Areas: Methodologies, tools, and criteria for decision-making

Achieving universal electricity access in rural areas remains a complex challenge in many developing countries, particularly for communities located within reach of existing distribution infrastructure but not yet connected. In such contexts, decision-makers must often choose between extending the main grid and deploying off-grid systems. This study presents a structured scoping review based on bibliographic sources, aimed at identifying how decision-making processes are supported in selection of rural electrificationstrategies, when both options are technically and economically viable. Following the PRISMA-ScR guidelines, a multi-phase filtering strategy was applied to the Scopus database, covering literature published between 2013 and 2024. A total of 3780 documents were initially retrieved, from which 136 were selected for in-depth analysis. Data extraction, co-citation mapping, keyword clustering, and thematic coding were used to classify the literature into five decision-related domains: technology selection, network configuration, system optimisation, policy frameworks, and multi-criteria methodologies. The review identifies recurring methodological patterns and systematises the decision-making criteria most frequently applied in rural electrification planning. It highlights that current approaches often treat grid extension and off-grid alternatives within isolated frameworks, despite their coexistence in practical planning scenarios. The analysis reveals significant gaps in the integration of technical, economic, social, environmental and institutional dimensions, as well as in the use of unified indicators that enable meaningful comparisons. These findings emphasise the need for more comprehensive frameworks that reflect the complexity of electrification choices in grid-adjacent rural areas and support more consistent, evidence-based planning processes. • A scoping review of 136 studies assesses decision-making in rural electrification planning. • Literature is categorised across five thematic domains using bibliometric and qualitative methods. • Decision-making tools lack integration of institutional and social dimensions. • Criteria used across studies remain heterogeneous and rarely comparable. • Findings reveal fragmented frameworks for planning trade-offs between grid and off-grid options.