Abstract
The Open-Source Tidal Energy Converter (OSTEC) project aims to design, construct, and deploy an
instrumented tidal turbine in a real marine environment, serving as a versatile testbed for research and
development. With a 2.5-meter rotor diameter and 26 kW rated power, the OSTEC turbine operates at meaningful Reynolds number scales and generates open-access datasets on power performance, mechanical loads, and tidal inflow conditions. A key focus of this project is the power take-off (PTO) subsystem, which plays a critical role in the energy conversion process of tidal turbines. This article outlines a structured methodology for designing and selecting a suitable PTO subsystem, using the OSTEC turbine as a case study. It emphasizes the main factors affecting PTO integration in marine energy devices and presents findings from the laboratory-based development, integration, commissioning, and testing of the PTO within the broader turbine system. The insights gained are intended to streamline future design and prototyping efforts, enabling more efficient and informed PTO subsystem selection in tidal energy applications.