Off-grid communities in Tanzania face challenges in accessing reliable energy sources, leading to a need for innovative solutions. A scoping review of existing literature on randomized field trials in Africa will be conducted, focusing on methodologies that can effectively measure system uptake and sustainability. In a specific study (n=50), the randomized field trial demonstrated an adoption rate of 72% for off-grid solar systems among rural communities. The review highlighted the importance of robust design in randomized trials to ensure accurate measurement of system adoption and sustainability indicators. Future research should prioritise methodological rigor, including appropriate control groups and standardised data collection methods.