Wave energy: supplementing the energy transition 

Validating and optimising wave energy converters

Wave energy converters (WECs) are not developed at Deltares itself. Deltares supports those inventors and developers, as well as investors, from our independent position. For example with questions about conditions in the nearshore area.

WECs are suitable for all open waters around the world. However, the best location for them does depend on the design of the devices. WECs must also be able to cope with factors such as storms and salt water. This is difficult and it requires a multidisciplinary field.

Using our unique research facilities, we help WEC inventors, developers and investors to validate and optimise the operation of single or multiple devices. Or we study the interaction when you put several of them together. We use our research facilities and our knowledge of wave development and wave propagation here.

‘By testing and validating WECs in the development phase in the controlled environment of the facilities, we avoid the challenges of testing on the open sea. That saves time and money,’ says project leader Jan Kramer as he explains the benefits of testing in the research facilities. ‘That’s because, at this stage, you can introduce new insights relatively easily and try them out immediately. You can also be sure that you can expose the WECs to extreme wave conditions. That’s not always the case during field tests.’

Future perspective of wave energy

Ensuring that wave energy can be used widely: that is the Deltares goal in collaboration with current developers and future stakeholders. Wave energy is still in the development phase. We can already test and verify how scale models work at different technology readiness levels in different conditions.

To determine, for example, the effects after the installation of multiple WECs, larger-scale research with one or more devices is needed. Positive effects, such as working with offshore wind (synergy) and creating new habitats, as well as negative effects such as the possible reduction of efficiency, may play a role here.

More extensive testing and research for energy from waves helps to determine whether this option can make a meaningful contribution to the energy transition. Deltares is eager to connect with developers and investors to take the next step.

Wave energy is still in the development phase, with different parties and at different technology readiness levels. Research is needed to determine what, and particularly how large, the benefits may be. Wave energy could therefore also become interesting for energy, oil and port companies.

Project leader Jan Kramer about the future of wave energy

Co-creation and use of knowledge 

Co-creation and making knowledge usable is an integral part of our approach. Deltares:

• Makes its knowledge available for universities and other institutes, with whom it seeks to collaborate.
• Tests and validates new and existing WEC concepts, for example in our facilities.  
• Models wave development and wave propagation from large-scale to detailed levels with software such as SWAN, PHAROS, CFD (StarCCM and OpenFoam) 
• Deploys measurement and monitoring techniques. Examples include measuring waves, forces (pressure), flow velocities, displacement, etc. 
• Studies the impact of WEC farms on the locality, nature and the coast (scour studies, ecological and morphological impact studies).  
• Advises on the technical feasibility and technical development of WECs and WEC farms. 

Deltares projects in the field of wave energy

Slow Mill tests in the Delta Basin

Three different studies have been conducted at Deltares for the Slow Mill project. In the process, one scale model of the Slow Mill device was tested in the Delta Flume. Several WECs are needed to use wave energy. An initial study was conducted in the Delta Basin with five Slow Mill devices. That involved examining the interactions in a configuration and the effect of the devices on the wave field.  Following on from that, an initial numerical study was conducted to determine the morphological effect of a line of Slow Mill devices offshore Texel.

Dutch Wave Energy tested in the Delta Flume

During the summer of 2020, tests were conducted in the Delta Flume to validate computer models, and the efficiency and operation of the prototype developed by Dutch Wave Energy. It emerged that the prototype worked well and the efficiency of the WEC exceeded expectations. As a result, Dutch Wave Energy is now one step closer to its mission of unlocking wave energy. And of putting this form of power on the map in the Netherlands.

By conducting efficiency tests in the Scheldt Flume, Deltares has helped WeCo, a young start-up, to make progress with their WEC design. Watch the video below for Luc and Eert’s story. As the winner of the SME facilities challenge, WeCo had the opportunity to use the Deltares knowledge and facilities free of charge.

Energy Harbour

Deltares thought up the concept of the “Energy Harbour”: we use our knowledge to concentrate wave energy in a particular spot rather than repel it. An energy harbour is a conceptual idea targeting the creation of the “ideal” local wave conditions for producing wave energy. This method allows us to make specific areas along the coast more economically interesting for this form of energy production.