Tidal energy is one of the most promising renewable energy sources, although less developed compared to others like solar or wind power. It is based on harnessing the tides, the movement of water generated by the gravitational pull of both the Moon and the Sun on the Earth. Although this energy has immense potential, cost and technological challenges have hindered its development globally.
Thanks to a European Union-funded project called FLOTEC (Floating Tidal Energy Commercialisation), significant progress is being made. This project has succeeded in manufacturing a turbine that is not only efficient but is approaching performance levels similar to offshore wind turbines. The project has served as an example of the path that developments in this sector must follow to make tidal energy a viable and competitive option in the near future.
Development of an efficient turbine
The FLOTEC project has manufactured a turbine that has marked a milestone in the history of tidal energy, generating more than 18 MWh in a 24-hour period of continuous operation. This level of efficiency is remarkably close to the performance of offshore wind turbines, opening up a world of possibilities for the commercialization of tidal energy.
This achievement is significant, as, until recently, tidal energy had not evolved as much as other renewable energies. The advantage of tidal turbines is that they take advantage of the greater density of water compared to air, allowing more kinetic energy to be captured with each rotation of the blades.
One of the key improvements that has allowed the efficiency of the turbine developed by FLOTEC to increase has been the increase in the rotor diameter, from 16 to 20 metres. This change has increased energy production by 50%, a crucial leap forward in making this technology an energy-efficient option.
Advantages and challenges of tidal energy
The main benefit of tidal energy is its predictability . Unlike other renewable sources such as solar or wind power, tidal energy has the advantage that tides are predictable events, allowing for efficient planning of electricity production.
However, the challenges to its full development are considerable. The marine environment is complex, requiring robust engineering capable of withstanding extreme conditions such as saltwater corrosion, biofouling (the accumulation of organisms on surfaces), and cavitation erosion. Furthermore, constructing underwater infrastructure entails high installation and maintenance costs.
Another key challenge is environmental impact . The turbines must be designed to avoid negatively impacting marine life, such as mammals or fish. In this regard, the FLOTEC project has made significant progress by integrating technologies that minimize these impacts, which is essential for obtaining regulatory approvals and minimizing public objections.
Tidal energy projects around the world
One of the most significant projects in terms of scale is the MeyGen tidal power system in Scotland, which represents the largest array of operational multiple turbines in the world. This 6 MW system has exported almost 25 GWh of electricity to the National Grid since its Phase 1A installation, covering the average annual consumption of approximately 3.800 British homes.
In terms of innovation, the ELEMENT project has also made significant contributions, developing an intelligent control system that optimizes turbine performance by anticipating and better managing the mechanical loads that affect their operation. This type of technology could increase turbine lifespan and reduce energy costs by more than 17% over their entire lifecycle.
Future initiatives and developments
Another significant advancement is the Orbital Marine Power O₂ turbine, considered the most powerful in the world with a production capacity of 2 MW . This technology is already operational in the Orkney Islands, UK, and has the capacity to supply 2.000 homes annually, in addition to contributing to the production of green hydrogen through electrolysis.
The EU-funded D2T2 project has also made progress in reducing operating costs by eliminating gearboxes in turbines and using a direct drive system, enabling electricity generation with low-speed currents. This technological advancement has reduced tidal energy production costs by 30%. Similar projects, such as NEMMO, are improving blade materials to resist erosion and the effects of biofouling in complex marine environments.
Tidal energy, although still in its early stages compared to other sources, is a technology that has the potential to become one of the main renewable energy sources of the future. Current research efforts and advances in efficiency are paving the way to a cleaner and more sustainable future, in which renewables play an increasingly predominant role. Thanks to its predictability, tidal energy offers significant advantages over other renewables and with adequate infrastructure and greater investments, it could go from being a promise to a tangible reality.