Open Sea Operating Experience to Reduce Wave Energy Cost

EU_flagThis project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 654.444


millions of euros


years of data


cost reduction

Follow us in


The project

Wave energy is forecast to have the potential to supply some 10% of European electricity needs; about half today’s total renewable generation. Due to its phasing, wave power complements solar and wind power and thus facilitates the practical integration of more renewables in the European grid.

Europe is currently the world leader in wave energy and thus there are significant opportunities for green jobs associated with its development and deployment. Wave energy costs remain high compared to con-ventional forms of energy. There has been very limited open-sea experience to fully understand the challenges in device performance, survivability and reliability. The limited operating data and experience that currently exists are rarely shared, since it is often partly private-sponsored. OPERA will remove this roadblock by delivering, for the first time, open access, high-quality open-sea operating data to the wave energy development community.

OPERA will collect, analyse and share open-sea operating data and experience to validate and de-risk several industrial innovations for wave energy, taking them from a laboratory environment (TRL 3) to a marine environment (TRL 5), opening the way to long term cost-reduction of over 50%

Floating OWC Wave Energy Converter development has received 2.5M€ funding from the Basque Energy Agency under the Pre-commercial Procurement Contract DIRTEC/14/008


To collect, stream and publish 2 years of open-sea operating data of both a floating WEC and a shoreline wave power plant


To de-risk innovations that lower mooring cost over 50% and enhance survivability


To increase OWC power production 50% and improve reliability


To advance predictive and latching control to enable 30% increase in power production


To advance standards to reduce business risk and give access to lower cost capital

To reduce uncertainty, frequency, risk and cost of offshore operations

To improve risk management and cost estimation with real data

To maximise impact on the entire value chain and society for wave energy

Exploitable results

Floating OWC Device: The buoy hull moves in the opposite direction to the water column inside the spar for the most typical wave periods. The oscillation in the column drives a low speed air turbine that is placed above the sea level. The rotor is the only moving part of the turbine resulting in higher reliability and more cost-effective production.

See Video

Novel bi-radial turbine: A novel radial self-rectifying impulse air turbine for use in Wave Energy Converters that is both mechanically simple and reliable. Exhibiting reduced pressure losses in comparison with current designs, this turbine is extremely compact axially, has the highest known efficiency amongst air turbines, over 70%, and a silent operation. The possibility of increasing the rotational inertia can easily be achieved to enable kinetic energy storage. The design includes a cylindrical axially-sliding stop valve in series with the turbine.


Advanced control algorithms: Several studies have shown the great potential of using advance information on incoming wave in controlling WECs. Predictive control uses incoming wave information for control, applicable to all WECs.  Latching (valve control) is specific to OWC.


Shared mooring systems: Shared mooring systems have long been used in aquaculture farms, where they can reduce mooring costs by nearly 50% in large farms at deeper deployments. Similar cost reduction is expected in deployment of over five devices for wave energy.


Elastomeric mooring tether: Compared to conventional mooring ropes, elastomeric tethers have load-extension characteristics that permit very significant reduction in peak loads and fatigue loads within the mooring system and at the hull connections thus reducing the costs of these structures whilst improving reliability.


Project development services: These services involve open-sea testing and validation services, guidelines and standards for ocean energy, services related to the engineering and construction of wave energy farms and seakeeping, installation and O&M services.


Project Structure

Test Facilities

LABORATORY TEST: The cost-reducing innovations for open-sea wave will undergo thorough lab-testing in order to de-risk them. The biradial turbine will be tested in test rig in which a centrifugal fan provides the pressure drop. The elastomeric tether will be tested in a purpose built test rig that aims to replicate the forces and motions that it will be subjected to in offshore applications. The turbine is connected, via a torque meter, to a motor-generator, which controls the speed using a stepless variable speed controller. Finally, the advanced controls will be tested in rotary test rigs which mimics the mechanical output of Ocean Energy Devices. It comprises a generator and a supervisory control system to optimise the control-law of the power take-off.

MUTRIKU OWC Plant: Mutriku Oscillating Water Column plant is the first multi-turbine wave energy facility in the world. It is integrated with the breakwater of Mutriku (Basque Country, Spain) and it has 16 air chambers and 16 sets of “Wells turbines + electrical generator” of 18.5 kW each. The plant was connected to the grid in July 2011. One of the air chambers is able to host new concepts of air turbines, electrical generators or control systems to be tested without grid-connection.

BiMEP: BiMEP is an open sea test centre of 5.2 km2 with depths going from 50 to 90m. It is located in an area with high energy potential (21kW/m) and its proximity to the nearest port (1 nmi) guarantees fast access. The area has a strong and nearby coastal utility grid (132kV-20MW capacity). Bimep is equipped with four berths of 13,2kV/5MW each connected to the grid, environmental monitoring services and 24/7 surveillance and emergency response.


Design of oscillating-water-column wave energy converters with an application to self-powered sensor buoys

J.C.C. Henriques*, J.C.C. Portillo, L.M.C. Gato, R.P.F. Gomes, D.N. Ferreira, A.F.O. Falc~ao
LAETA, IDMEC, Instituto Superior Tecnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal


The quest for conquering the ocean and understanding its behaviour has been a challenge with increasing needs for innovation and technology investments in many areas of strategic value for the promotion, growth and competitiveness of the marine economy worldwide. Current oceanographic buoy systems are limited to low power levels and intermittency of data acquisition and transmission, among other aspects that need to be overcome to comply with new and more demanding applications. The development of marine activities requires more powerful and reliable data-acquisition systems to guarantee their future sustainability. This work presents a new systematic methodology for optimum design of wave energy converters. The methodology was applied to design two self-powered sensor buoys for long term monitoring based on the oscillating-water-column principle. The optimisation focussed on buoy hydrodynamic shape, sizing and selection of the turbine and the generator, as well as the control law of the generator electromagnetic torque. The performance was assessed through the use of the power matrix and a set of performance indicators. These performance indicators were defined to allow a simple comparison between different wave energy concepts. The results confirm the applicability of the designed buoys for a next generation of oceanographic monitoring systems.

Elsevier – Energy – Volume 112, 1 October 2016, Pages 852–867


Follow us inLinkedIn-02


OPERA Consortium awarded the Yoshio Masuda Memorial Price at EWTEC 2017

OPERA received the Yoshio Masuda Memorial prize for its contribution to the 12th European Wave and Tidal Conference (12th EWTEC). This Conference was focused to the commercialisation of the marine energy sector with over 500 delegates presenting over 300 scientific presentations over four days. Opera consortium was awarded for its multiple high-quality conference publications that informed about the developments of the OWC systems in the Mutriku Wave Power plant and the OCEANTEC’s MARMOK-A-5.

read more

First practical experiences of open-sea operation. Workshop at the Bilbao Marine Energy Week 2017

The first industrial workshop of OPERA has taken place at the framework of The Bilbao Marine Energy Week (March 2017). Around 80 persons attended this workshop aimed at learning from the first practical experiences of open-sea operation, identifying common challenges, best practices and needs. The workshop brought together technology and project developers, marine contractors and test sites/pilot projects as catalysers of experience generation.

read more

First OPERA video already available

Olatz Ajuria, project leader at the Basque Energy Board (EVE), introduces OPERA and its main objectives, along with the deployment activities of OCEANTEC’s MARMOK-A-5 device at BiMEP. Led by TECNALIA, the OPERA project will collect, analyse and share open-sea operating data and experience to validate and de-risk four industrial innovations for wave energy opening the way to reduce cost by 50% in the long term.

read more


2018 · June · International Conference on Ocean Energy (ICOE)
Date: June, 2018



Place: Normandy

Link to the event information

2017 · August, 27 - September, 2 · EWTEC2017 - 12th European Wave and Tidal Energy Conference
Date: August, 27 – September 2, 2017



Place: Cork, Ireland

Link to the event information

The latest in the foremost bi-annual scientific conference series on Wave and Tidal Energy will return to the historic city of Cork, Ireland:

  • Scientists and experts in the fields of marine renewable energy will reveal their latest advances
  • Exhibitors will present exciting new products and services
  • Abstract submission open from October 2016
  • A selection of the submitted papers will have the opportunity to be published in the International Journal of Marine Energy (IJoME)


2017 · March, 27-31 · III Marine Energy Week
Date: March 27-31, 2017



Place: Bilbao, Spain

Involved Partners: TECNALIA, EVE

Link to the event information

2017 · January 20 · 2017 Maynooth University Wave Energy Workshop
Date: Friday, January 20, 2017 – 08:30 to 18:00

Place: Glenroyal Hotel, Maynooth

Involved Partners: TECNALIA, EVE

Link to the event information

2016 · November, 8-9 · Ocean Energy Europe 2016 Conference & Exhibition (OEE2016)
Date: 8 and 9 November 2016

Place: Brussels

Link to the event information

 will OEE2016 offer?

  • A busy 1250m2 exhibition hall, showcasing the latest projects and products from the key players in ocean energy
  • A topical, high-quality conference programme with a strong focus on finance, featuring high-level politicians and decision-makers, and the biggest names in the industry
  • Unrivalled networking opportunities with 400+ professionals from across Europe and beyond, representing all parts of the value chain
  • A broad range of side events, including the Ocean Energy Forum’s grand finale, taking place alongside the main event

The key players in the ocean energy sector will be there in force at OEE2016.

Visit OPERA at the stand 24 in the OEE2016

2016 · June, 1-2 · Seanergy
Date: June 1-2, 2016



Place: Biarritz, Halle d’Iraty

Involved Partners: TECNALIA, EVE, OCEANTEC

Link to the event inform


2016 · May, 3 · From Seaenergies to Seanergy - Workshop #4
Date: May 3rd, 2016



Place: Tecnalia, Parque Tecnológico de Zamudio

Involved Partners: TECNALIA, EVE

Link to the Workshop #4 information

2016 · Febr, 23-25 · ICOE 2016 - Edinburgh
The 6th edition of the International Conference on Ocean Energy (ICOE) has taken place on the 23th to 25th of February 2016 in Edinburgh. ICOE 2016 is organised and hosted by RenewableUK.



Link to the event:

For more information please contact

Mr. Pablo Ruiz-Minguela (Tecnalia)

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 654.444