Coastal infrastructures and most islands have specific energy needs, many suffer limitations to attain energy decarbonization, but they also have privileged access to the sea and its energy potential. SDK Marine is the wave energy division of Sendekia, a Spanish company funded in 2007 to innovate, produce and install equipment for the generation of renewable energy, sustainability solutions and the circular economy. SDK Marine’s mission is to harness wave energy to efficiently turn it into electricity, to make it convenient available and abundant to facilitate the energy transition of ports and islands. The solution is a Wave Hydro Turbine (WHT) working inside an Oscillating Water Column (OWC) which harness best the full energy of waves. Our technology transforms water movement directly to electricity, without any intermediate transformations and fully profiting its density and lack of compressibility. The patented unique turbine allows to equally profit from upward movement of water, as well as, from its descent. Our wave energy solution is compact and installed at shore and does not require offshore maintenance, nor any offshore expensive subsea high-voltage lines. Videos on the technology test prototype unit installed on the breakwater of the Mediterranean port of Cartagena, Murcia, Spain, can be watched at: Buoy at the pier of Cartagena: https://youtu.be/1J2IaTypjts Unusually high waves at Cartagena: https://youtu.be/px0epQbPdyM A short presentation can be seen at: https://youtu.be/RahaMeLfLfY


SDK Marine is the creator of the Wave Hydro Turbine (WHT) technology. Engineered based on over 20 years of hydropower track record and achieved innovations in the field. Hydroelectric technology directly applied to wave power.

Water is 800 times denser than air and it is not compressible like it. Direct interaction of water with the Power Take Off device and generator is the best option to maximize the capture maximum torque from the movement of waves.  Torque is greatly needed for the generation of electricity.

The SDK Marine’s technology and WHT is based on an innovation not seen yet in any other wave energy device in advanced state of development. The special patented turbine allows:

–       Continuous rotation in a single direction regardless of the direction of the waterflow in the column. It also allows maximum capture of power in both directions.

–       Torque rich rotation due to self-adjusting turbine blades in the adequate position against the water flow

–       Direct conversion from OWC water flow into rotational movement, avoiding derivatives such as hydraulic fluids, compression of air or others, as well as, eliminating additional energy losses in the chain of processes.

–       Maximization of the water movement amplitude inside the OWC thanks to the harnessing of resonance.

–       Profit from the mirror effect caused by the breakwater wall

Our technology has been proven to work in a Mediterranean port attached to the breakwater at the Port of Cartagena in Spain. It has withstanded storms in the previous test in the Mediterranean.   Our solution is perfectly suitable to be installed in ports such as Giglio’s and will surely meet this challenge requirements.

The SDK Marine wave energy solution is fully friendly, thanks to its features:

–       A very limited visual impact due to its size and since the bouy is made out of Hi performance concrete it blends with the port breakwater and structure.  The buoy for the Giglio Island application will be cylindrical and approximately 3 meters in diameter and 6 meters high.  The buoy floats with about 3,0 to 3,5 meters inside the water so only a maximum of 3 meters are visible above the sea level.

–       It takes almost zero usable ground space. It does not interfere with the navigation of ships coming to the port and it is comparably a compact renewable solution.  It will take under 400m2 to install 1 MWp

–       It has minimal environmental impact as it has minimal moving parts in contact with the water, it uses only biodegradable lubricants which are all contained in sealed compartments.  Materials selected for its fabrication are suitable for sea environments such as a concrete external structure, composite parts and special bushings are used

–       The at-shore energy generation minimizes the installation and operational CO2 footprint since no ships need to be used for operation. Also, no underwater costly high-voltage electric lines are needed

–       Turbine and moving parts are protected and designed in a way that avoid any harm sea life

The technology due to its buoyancy principle is works in the same fashion when placed at-shore by the breakwater or when it is placed off-shore.

Due to its modularity, our technology can be displayed from 100KW to multiple Mega Watts of installed capacity.  In an initial estimation, according to current efficiency and the available space in the external breakwaters of the Giglio Island Port up to 300 to 400 homes could be powered by the execution.


Our proposal is to study and execute the customization of the WHT set for the external breakwater of the port of Giglio.  Two (2) prototypes are proposed for the Installation and testing, de-risking and optimization to local sea conditions and Port needs.

Depending on Giglio’s port needs, they could be either installed by the port breakwater or offshore at 1 to 2 Kms off-shore close to the port

In the following image is a schematic representation of a possible installation in the Giglio port breakwater is shown for the at-shore execution.

In the following image is a schematic representation of a possible installation in front of the Giglio port shown for the Off-shore execution.

On a second phase of the project, once tested over 6 to 12 months, a rollout of optimized units would take place to multiply installed capacity, and thus, allowing the port to:

–       Minimize electrical dependence from the grid

–       Allow decarbonization of some of the current fossil fuel powered operations

–       Prepare itself for higher energy demand due to:

o   New and lowered emissions regulations

o   Electromobility

o   On-site production of green Hydrogen for truck load and sea transport


The current energy paradigm shift we are living will require all available renewable and sustainable sources of energy.  Sustainable according to the ESG taxonomy, not just limiting CO2 emissions, but also, avoiding harming the environment or other activities and optimizing resources needed.

The WHT from SDK is designed to maximize circular economy including recycled materials in the manufacturing processes.  Designed for the use of minimal carbon footprint materials available. The manufacturing process of the structural buoy, which is the biggest element of the solution, allows for a flexible construction site, close to commissioning location.  The process also, allows local assembly.  This in turn besides reducing transport cost and CO2 footprint, but also promotes local qualified jobs during manufacturing.    Foreseen maintenance operations allow more flexible local O&M contracts, thus fostering long term local jobs.

A rolled-out installation by the Giglio port could supply energy to an estimated of 300 to 400 homes.  This in turns will also offset its own carbon footprint in less than 11 months.

An extended installation off-shore could be sized to supply all the energy needed in the island and sufficient energy for the generation of green hydrogen for the future decarbonized sea transport.

Giglio could become the first fully decarbonized island in Italy with a state of the art compact and scalable solution


Sendekia, a Spanish company funded in 2007 by engineers with a vast experience and international track record in Hydropower and deep knowledge in design, R&D, product development and manufacturing

Sendekia S.L. was founded with the mission to innovate in construction and energy solutions.  Back in the days renewable energy equipment where developed such as single and double axis solar trackers.  Later, solar powered parking lots roofing with electric vehicle charging stations. Other technologies were developed such as Hydro Low Head for variable flow, speed and pressure solution to improve efficiency and profitability of mini-Hydropower plants. Circular economy projects and technologies have been created such as a recycled material to greatly enhance resistance of concrete.

In 2013 the SDK Marine unique turbine rotor was born.

The SDK Marine technology has received EU funding by the Marinet Fund for testing and won the support from Repsol in a 2-year incubation program that ended in the real condition test in the port of Cartagena, Murcia.

A video of the testing can be seen at: https://www.youtube.com/watch?v=zJav2KVa0PU

Since 2019 SDK Marine has advanced in the preparation of the new generation of the WHT which includes various optimizing improvements, allowing for a considerable increase in wave matrix adaptability, as well as, widening the power matrix and increasing the power output.

During this period new partners have come to collaborate with SDK Marine, such as Danfoss for the power electronics, Wavec, for the numerical analysis and adaptation to new executions and conditions.

Since 2020 SDK is in conversations with the Balearic Island institutions in order to set up a prototype test in a Balearic port. The test is intended to prove production and reach commercial state of the solution

Recently Wavec, Danfoss, TYPSA and SDK Marine participated in a Consortia as a tenderer in the Europe Wave program for public purchase of an off-shore pre-commercial wave energy solution.

The team:

Manuel Grases Galofré:

Founder and CTO of Sendekia and SDK Marine, Mechanical Engineer and Hydraulic Engineer and Master in Mathematical Models in Hydrology from the University of Grenoble, France. Researcher and Inventor Manuel has more than 35 years of experience, among others, as part of the development of engineering projects and construction of facilities such as Aqueducts, River Bridges, Tunnels, Hydroelectric Dams (INGA dams in Zaire and Guri In Venezuela)., a company that creates and develops technologies for and for the generation of renewable energies and inventor of the patented turbine for continuous motion marine waves. Inventor of the continuous motion marine waves turbine, the base technology for this project, has Carried out the coordination of the complete R&D process of the Wave Hydro Turbine at-shore solution

José Manuel Grases Mendoza:

Chief engineer and Founding member of Sendekia and SDK Marine. Industrial engineer from UPM University of Madrid with a wide range of understanding in different engineering fields, 3D printing, product design, machine design, R&D, structures, electro mechanics, offshore engineering and wave energy. With proven track record in different engineering multinational organizations and major industrial projects. Savvy researcher and product developer.

Founding member of Sendekia, was Chief Engineer during the R&D of the continuous movement wave turbine, as well as, responsible for the manufacturing of the Cartagena prototype and test.

Antonio Canyellas:

Chief Commercial Officer in SDK Marine: Entrepreneur and Business Owner, with over 25 years of international business development track record. He has built international sales organizations and distribution channels for tech based and industrial equipment solutions. Natural from the Mallorca. He joined SDK Marine to attain initial pilot plants and to drive commercial growth

Guillermo Souto Zirovnik:

CEO in SDK Marine. Renewable energy professional with over 25 years of proven track record international business development with previous experience in different industrial sectors including machinery and industrial energy back-up services. Launched new commercial operations from zero. Holding a solid education as Industrial Engineer and MBA.

As consultant, he has managed complex projects to optimize and restructure business units, leading multidisciplinary teams. Leaded industrial startups internationally.

Technically and financially savvy. Business integrator. Focused on technical B2B business solutions. He joined Sendekia to lead the final stages of development to turn the product into an industrialized and commercial product and to drive the company growth.