BACKGROUND Modern energy enables health service delivery. Access to electricity is, however, unreliable in many health facilities in developing countries. Little research has explored the relationships between energy and service delivery. METHODS Based on extensive literature searches and iterative discussions within the research team, we first develop a conceptual framework of the role of energy in health facilities. We then use this framework to explore how characteristics of electricity supply affect distinct energy uses in health facilities (e.g. lighting), and how functional or non-functional lighting affects the provision of night-time care services in Malawi. To do so we apply descriptive statistics and conduct logistic and multinomial regressions using data from the Service Provision Assessment (SPA) of the Demographic and Health Surveys (DHS) for all health facilities in Malawi in 2013/2014. RESULTS The conceptual framework depicts the pathways from different energy types and their characteristics, through to distinct energy uses in health facilities (e.g. medical devices) and health-relevant service outputs (e.g. safe medical equipment). These outputs can improve outcomes for patients (e.g. infection control), facilities (e.g. efficiency) and staff (e.g. working conditions) at facilities level and, ultimately, contribute to better population health outcomes. Our exploratory analysis suggests that energy uses were less likely to be functional in facilities with lower-quality electricity supply. Descriptive statistics revealed a critical lack of functional lighting in facilities offering child delivery and night-time care; surprisingly, the provision of night-time care was not associated with whether facilities had functional lighting. Overall, the DHS SPA dataset is not well-suited for assessing the relationships depicted within the framework. CONCLUSION The framework conceptualizes the role of energy in health facilities in a comprehensive manner. Over time, it should be empirically validated through a combination of different research approaches, including tracking of indicators, detailed energy audits, qualitative and intervention studies.