Madrid researchers closer to cracking deepwater tidal challenge

Researchers from the Polytechnic University of Madrid (UPM) have developed procedures and designs to extract power from marine currents in deep areas while at the same time optimizing the cost of energy production.

One of the disadvantages posed by new devices designed to take advantage of the energy of marine currents at high depths is their high cost of manufacturing, installation and maintenance, according to UPM.

To address this problem, members of the Technological Research Group in Marine Renewable Energy (GITERM) of the UPM have developed a method for analyzing the lifecycle cost of a power generation parsk based on these devices – which can be used in early design phases, according to UPM.

“It is estimated that around 80% of the energy of currents is located in areas of more than 40 meters deep, so it is necessary to use new designs of devices that can operate in these areas where the cost of a large structure fixed to the sea bottom makes the first generation solutions unfeasible,” the UPM said.

On contrary, the second generation tidal technologies have anchoring systems with a fixed base or anchor in the bottom and a series of cables that hold the device to the seabed, according to UPM.

Amable López, a researcher of the GITERM group, said: “Our GESMEY device, patented by the University, has been the first sea-tested design in the world to work fully submerged. Thanks to the cost analysis tool developed, we have been able to evaluate different design alternatives with a final objective: to reduce as much as possible the cost of energy production and to make this renewable source competitive – from both technical as well as economic point of view.”

These economic analyzes are integrated into the development of new anchoring systems that are simpler and more robust – as shown in a paper published this year in the Ibero-American Journal of Automation and Industrial Computing.

Simulation of the operation of a Hive-TEC device with its anchoring system (Image: UPM)

For the development of these systems, powerful simulation and control tools have been used, which were also developed within the GITERM group, the UPM said.

Thanks to these procedures and tools, the initial design of the GESMEY device and its anchoring system has evolved from generators with a large rotor – similar to that of wind generators – to generators with several rotors, such as the Hive-TEC device, according to the UPM which also patented the device.

The employment of new methods has resulted in lowering the estimated cost of energy produced by Hive-TEC by 30%, the UPM informed.

The GITERM group added it is continuing the work to achieve a successful commercialization of tidal renewable energy devices since the potential to generate electricity from marine currents is enormous.