This document summarizes research on financing off-grid energy access. It finds that third party financing has increased adoption of technologies like rooftop solar in the US. Pilot projects in Millennium Villages using pay-as-you-go microgrids demonstrated that most customers maintained positive balances over 90% of the time. Data from these projects can provide insights into technical improvements and their costs. The document also discusses the importance of considering reliability versus cost in system design and examines how financing structures and perceived returns affect adoption and payback periods for different technologies.