Sharks and seaweed inspire green energy
Researchers in Australia are looking to sea plants and shark tails as inspiration for ways of extracting energy from ocean waves and tides
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Dr Tim Finnigan at the University of Sydney has formed a company, BioPower Systems, to commercialise the technologies. The wave energy system is called “bioWave” and has long, vertical blades that sway back and forth. Dr Finnigan says that it, “Is the only wave energy system that captures a wide swath of incident wave energy without using a large rigid structure. It is also the only such device that absorbs energy over the full water depth and continually self-orients with the wave direction”.
The blades are attached to an “O-Drive” generator, which uses a single stage reciprocating gear mechanism with a direct-drive synchronous permanent magnet generator and a high-inertia flywheel. In extreme wave conditions, the generator is back driven to ensure that the blades assume a safe position lying flat against the sea bed. Systems are being developed for 500kW, 1000kW and 2000kW capacities.
The shark tail machine is called, “bioStream” and mimics the shape and motion characteristics of shark, tuna and mackerel tails, but is a fixed device, designed to be used in a moving stream or tidal flow. In this configuration the propulsion mechanism is reversed and the energy in the passing flow is used to drive the device motion against the resisting torque of the generator.
More information from BioPower Systems
