Multi-use marine energy platforms: wave and tidal power

The ocean stores inexhaustible energy: waves have the potential to generate more electricity than current global consumption (PierNext).

The potential of marine energy

The oceans store inexhaustible energy that current technology can convert into clean and predictable electricity. Wave energy harnesses the constant force of waves to generate up to 29,500 TWh annually —exceeding global electricity consumption in 2022—, while tidal energy uses the cyclical and predictable movement of tides 24 hours a day. Both technologies are evolving towards multi-use platforms that combine multiple renewable sources in a single installation, maximizing profitability and transforming marine infrastructure into authentic energy microgrids.

In a context marked by the urgency of decarbonization and technological innovation, multiple international projects are harnessing the energy potential of waves and tides. Wave energy leads this revolution due to its greater generation potential, attracting significant investments in technological R&D.

We analyze at PierNext the latest innovations in marine energy and their real applications with the perspective of ongoing examples and the context of an expert in marine sciences.

Wave energy: harnessing the force of waves

It is calculated that wave energy, which harnesses the force of waves, has the potential to generate up to 29,500 TWh per year (that is, slightly more than what was consumed worldwide in 2022).

The Basque success case: Mutriku

The Mutriku wave power plant in the Basque Country represents a global technological milestone. This installation produces 300,000 kWh annually and has reached an accumulated electrical production of three million kWh. As the world's oldest commercial wave energy plant and the one with the most operating hours, Mutriku became the first installation to achieve this historic production figure.

Tidal energy: harnessing the force of tides

Tidal energy harnesses the force of tides to generate electricity continuously and predictably. During the 24 hours of the day and seven days of the week, the large oceanic water masses move following regular cycles that allow precise energy planning.

Featured projects in Europe

The MeyGen project already supplies energy to nearly 4,000 homes on the north coast of Scotland, demonstrating the commercial viability of this technology. In parallel, Magallanes Renovables, a company with Galician roots, develops an ambitious project that aims to supply electricity to 11,000 homes in Wales from 2026, consolidating Spanish technological leadership in tidal energy.

Converter technology: kinetic and gravitational energy

Marine energy capture systems use specialized converters that harness the kinetic or gravitational energy of water. According to the International Renewable Energy Agency (IRENA), these devices employ different mechanisms: from converters that trap air pockets to drive turbines, to systems that directly use wave movement or water height differences.

Technical differences between systems

"To harness the energy generated by a wave, a vertical turbine is installed with several anchors and a flexible device —like a buoy— that floats on the surface. The up-and-down movement of waves displaces this structure, generating mechanical energy," explains Sergio Trigos,, professor of the Master's in Renewable Energy at the International University of Valencia (VIU).

"Tidal systems work differently: turbines are oriented horizontally to capture tidal flow. They have a dynamic rotor that, when rotating, activates an inverter that transforms movement into electricity," adds the expert.

The profitability challenge

Despite their potential, these projects face significant challenges: high investments less attractive than wind or solar, continuous complex maintenance, and the need for specific climatological conditions that limit viable locations.

This reality drives the development of dual or multi-use structures: installations that leverage marine infrastructure for multiple energy activities, optimizing investment and maximizing economic return.

Key points

What is wave energy and how does it work?

Wave energy harnesses the force of waves through converters with vertical turbines and floating devices like buoys. It has the potential to generate up to 29,500 TWh annually, exceeding global electricity consumption.

How does tidal energy differ from wave energy?

Tidal energy uses horizontal turbines to capture tidal currents (predictable 24/7 movement), while wave energy uses vertical turbines for waves (less constant movement but with greater energy potential).

What are multi-use marine energy platforms?

They are hybrid installations that combine multiple renewable sources (waves, tides, wind, sun) in a single structure, maximizing profitability and better leveraging investment in marine infrastructure.

The trend towards multi-use and multifunction

The concept of multi-use structures is transforming marine infrastructures into energy microgrids that simultaneously harness different renewable sources. According to Sergio Trigos, these hybrid projects optimize marine space: the submerged part captures the force of waves and tides, while the surface harnesses wind energy.

"Practically every day there is wind, so continuous wind energy is harnessed. Simultaneously, when there are waves or tidal movement, wave or tidal energy is generated. This trend leads in Nordic countries like Sweden and Norway —with ideal coasts and climate— and is rapidly expanding in Latin America, combining multiple sources of sustainable energy," explains the VIU expert.

Success case: NoviOcean

The Swedish company NoviOcean develops a hybrid energy plant that integrates solar, wind and wave energy in a single structure. Its installation is shaped like a raft 38 meters long by 6 wide, completely covered with solar panels and vertical wind turbines. After starting prototype testing in 2019, the company has received funding from the EU LIFE program for the complete deployment of its offshore technology.

Synergy between marine energy and aquaculture

Blue Growth Farm represents the perfect integration between renewable energy and marine food production. This pilot project, funded by the EU Horizon 2020 program, is defined as "a multifunctional, efficient, cost-competitive and environmentally friendly offshore farm".

The installation combines wind and wave energies to power a fully automated aquaculture system, structured around a central pool, storage areas, and a deck that integrates a 10 MW wind turbine along with several wave energy converters (WEC).

Specialized technology for marine farms

E-Wave Technologies has developed a different approach: wave energy converters designed specifically for the aquaculture industry. This sectoral collaboration has resulted in systems optimized to supply clean and accessible energy directly to marine farm infrastructures.

"This technology allows aquaculture companies to save costs and optimize energy resources. The generated electricity powers essential machinery, lighting systems and facility automation. It is already implemented in Ecuador and Honduras —major aquaculture exporters— and is expanding through Nordic countries," explains Trigos.

Challenges and opportunities of marine energy

The Mutriku wave power plant —Spain's largest and Europe's commercial pioneer— marks the path to harness marine energy potential. This success drives new Spanish port projects, such as future installations at Port Adriano (Mallorca)and Granadilla (Tenerife).

Advantages for port infrastructures

"For ports it represents a double opportunity: energy self-sufficiency and selling surpluses to the electrical grid, significantly reducing operational costs. Additionally, it adds value for companies in the port environment," explains Trigos. These advantages include greater sustainability and acceleration of energy transition, although technical, economic and regulatory challenges persist.

Technical and environmental challenges

"Offshore installations face constant mechanical wear from saltwater action and extreme temperatures. Environmental impact also requires innovative solutions, such as artificial marine habitats integrated in wind farms to preserve biodiversity," notes the expert, referring to the Éoliennes Flottantes du Golfe du Lion project by Ocean Winds.

Regulatory framework and financing

"The high investment cost makes these projects less attractive than solar or terrestrial wind energy. Tax incentives and regulatory benefits would be key for ports making significant investments, generating a positive multiplier effect on environment, society and local economy," concludes Trigos.

The future of multi-use platforms

Wave and tidal energies are experiencing a fundamental transformation towards integrated energy ecosystems. Multi-use platforms not only solve the profitability challenges that have historically limited these technologies, but also open new business possibilities by combining electricity generation, aquaculture and other marine activities.

With a global potential of 29,500 TWh annually and consolidated success cases like Mutriku, marine energy positions itself as a key piece of decarbonization. The development of favorable regulatory frameworks and technological maturation promise to accelerate the implementation of these energy microgrids that will transform our oceans into inexhaustible sources of clean energy and sustainable economic activity.

The marine energy revolution is no longer a future promise: it is a reality taking shape.

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