Experiments in the ocean: Development of a small-scale sea trial tidal turbine test rig

A system for generating renewable energy from fast flowing rivers has been designed in a previous project. It uses a purely mechanical system to pump pressurised water to shore. Here we describe the development of a 0.9m version of this system, designed for installation in a tidal estuary. The system is fully instrumented to allow power take off and control system testing and experiments. The main components which are of particular importance are: power take off, valves, chassis, safety braking, rotor blades, mooring, and sensors. Prior to deployment at the Marine Energy Test Area, Wales, UK, a laboratory test rig is used to test the power take off, valves, and sensors, with a motor replacing the rotor blades. Specification of the rotor blades and performance predictions of the system is achieved using a computationally efficient numerical model; blade element momentum theory. Final design drawings will be openly available which will facilitate application of the design and improvements by other collaborators. The remote river energy system design presented here is a platform to facilitate prototype technology trials to further develop the concept.