Japanese develop tidal current-powered smart buoy for ocean data collection

Nagasaki University and Kyocera Corporation have jointly developed a smart monitoring buoy which exploits tidal currents to generate its own energy for continuous ocean data collection.

Image showing Energy Harvesting Smart Buoys (Courtesy of Kyocera)
Energy Harvesting Smart Buoys (Courtesy of Kyocera)

The new smart buoy combines tidal-current power generation technology from Nagasaki University and the Internet of Things (IoT)-related technology from Kyocera.

Prototype buoys are said to be able to collect a wide range of data on the marine environment using self-generated energy.

The partners conducted a pilot test for nine days during spring tide to low tide in the tidal cycle. The test used 21 sensors to collect data on acceleration, temperature, flow velocity, and current direction, amongst others, which was then transmitted to the cloud.

The average amounts of electricity generated during the experiment reached 16.3Wh, and consumed on average 15.2Wh, the partners said.

Two prototypes have been developed, each equipped with two different tidal-current power generation systems.

In the SLTT prototype, short for small lens-type tidal turbines (pictured left), the buoy and power generation are separate, and a diffuser is installed around the turbine. In addition to protecting the turbine, the diffuser has the effect of increasing the flow of water for better power generation.

The VTT iteration, short for vertical-axis tidal turbines (pictured right), directly connects the power generation element to the buoy. Its AI-guided design incorporates a tilted axis to optimize turbine rotation amid heavy ocean swells and waves, according to developers.

To promote ongoing ocean monitoring, the project partners plan to add additional sensors to the buoys, including those measuring temperature-related salinity variation, chlorophyll turbidity, and temperature-related variations in dissolved oxygen concentrations, to name a few.

Performance and operation will be improved, along with a reduction in size and weight, in commercial versions, the partners noted.

Kyocera will also build an IoT platform to store collected data, and ongoing testing will be conducted mainly in Nagasaki Prefecture.