Potential of renewable energy technologies for rural electrification in Southeast Asia: A review

Rural electrification remains a significant development challenge in Southeast Asia, where over 45 million people still lack access to reliable electricity. This review uses a comparative analysis of empirical data and policy interventions across the region to evaluate the potential and barriers of renewable energy technologies (RETs) including solar, wind, biomass, and small-scale hydropower. The study aims to synthesize regional implementation outcomes, identify enabling frameworks, and highlight scalable hybrid solutions. Methodologically, over 100 published sources were reviewed to extract quantitative and qualitative data from key case studies in countries such as Vietnam, Indonesia, and the Philippines. Results show that solar PV systems, with a cost decline exceeding 80 % in the past decade, represent the most viable off-grid solution. Vietnam will achieve over 16 GW of installed capacity by 2022. Biomass energy contributes up to 15 % of rural energy use in Indonesia and Thailand, while small hydropower accounts for 20 % of rural generation in Laos and Vietnam. Hybrid renewable energy systems (HRES), integrating solar, wind, and biomass, reduce costs by up to 30 % compared to standalone systems and enhance supply reliability. However, deployment remains hindered by upfront costs (e.g., over $2500 per household for solar), limited technical expertise, policy inconsistencies, and socio-cultural resistance. The novelty of this review lies in its regional synthesis of RET policy impacts and its proposal of a diagnostic framework linking technology choice with socio-economic conditions. In conclusion, targeted subsidies, capacity-building, and community-driven models are crucial to overcoming barriers and unlocking RET's potential for inclusive, resilient, and sustainable rural electrification in Southeast Asia.