Researchers at the Group of R&D GITERM at the Higher Technical School of Naval Architecture and Ocean Engineering of the Universidad Politécnica de Madrid working with the Astilleros Balenciaga company and the Fundación Centro Tecnológico Soermar have built and tested a prototype of a device to harness energy from ocean currents that is able to work in deep water.
The team works together in the PROCODAC project, focused on the design, construction and testing in a marine environment of an experimentation prototype. They’re working at a one in ten scale of what would be an industrial unit able to provide 1 megawatt of electricity.
The test results as described by the university press release are described as very successful and have confirmed that this prototype can produce the expected energy and to be maneuvered by remote control, two items of great interest for use it in future underwater power plants.
The difference of the new work compared to older efforts is the first generation of systems of harnessing energy from ocean currents was only feasible in areas of maximum depth of 30-50 meters, because the generators were joined at the bottom, and maintenance was expensive.
The team’s second-generation systems came out anchoring systems with diverse solutions that allow us a submerged operation with the possibility to put afloat the main elements for its maintenance.
The main unit of the prototype is built as a structure of stainless steel with a central body and three peripheral parts joined by arms. The generator, the multiplier, and the instrumentation system are inside while the rotor that captures ocean currents is outside.
The photo above shows the 1/10th scale prototype held by a hand. The photo offers an estimation of scale but the unit appears to be suspended by a cable fully out of the water.
During the development of the project, tests of integration and the tuning were conducted in the LEEys Lab of the ETSIN and at the shipyard. They also conducted sea trials divided into tests of maneuvers and trailing. The project was complemented with a research on hydrodynamics and structures as well as maneuvers and energy control. These studies were embodied in various numerical simulations.
The test results have confirmed that the prototype has accomplished the objectives by reducing costs of construction, installation and maintenance. The development and construction of these units of marine renewable energy production are being shown as affordable for a medium sized shipyard.
The Spaniards look to be on to something worth pursuing. There is a massive energy store in the moving water of currents. The harvesting could be well worth the effort.
As with many renewable energy projects the harvest might be the easy part. Getting useful energy ashore could prove to be a research effort that needs attention as well. Not all currents and not all shorelines are going to have economically worthy matches. But for those that do, ocean current power, a steady unrelenting source, would be more attractive than the intermittent wind.