Rural communities in developing economies often remain beyond the reach of national grids, making decentralized renewable solutions critical for social and economic progress. This study evaluates the performance of an ultra-low-cost hydrokinetic turbine designed for shallow, slow-moving rivers typical of remote regions. A 1 : 5 scale prototype was fabricated using locally available materials and tested in a controlled laboratory flume across flow velocities of 0.4 – 1.2 m s⁻¹. Key performance metrics—power coefficient (Cₚ), tip-speed ratio (TSR), and start-up behavior—were recorded via torque transducers and flow probes. Results show a peak Cₚ of 0.31 at a TSR of 2.8, delivering a specific power of 38 W m⁻² at 1.0 m s⁻¹, sufficient to meet basic household lighting and phone-charging needs. The turbine demonstrated reliable self-starting at velocities as low as 0.35 m s⁻¹, indicating suitability for perennial low-head watercourses. A cost analysis projects a levelized cost of electricity of USD 0.07 kWh⁻¹ when scaled to full size and produced using community-level manufacturing facilities. These findings confirm the viability of simple, repairable hydrokinetic devices for accelerating rural electrification, reducing reliance on diesel generators, and supporting sustainable development goals in underserved regions.