“The Dikwe wave energy-generating system is in action off the coast of France”
ENERGY POSITIVE BREAKWATER SYSTEMS
https://interestingengineering.com/innovation/france-wave-energy-breakwater-system
Wave-powered panels turn sea walls into giant electricity generators
by Ameya Paleja / Jun 20, 2025
“Construction of the first full-scale breakwater system for harbors that doubles as a wave-based energy generator has begun in Boulogne-sur-Mer, northern France. The project is a collaborative effort between French institutes Ifremer and GEPS Techno, with construction responsibilities being handled by UK-based Legendre Group. In a bid to move away from fossil fuels, scientists are looking for cleaner approaches to meeting our energy demands. While wind and solar power projects are being scaled up, they also have intermittency issues, where power production stops when the sun does not shine, or the wind does not blow. Alternate renewable energy technologies such as tidal and wave energy generators tap into more consistent energy sources. Interesting Engineering has previously reported how different designs of wave energy generators are being trialed in various parts of the world. One such project is Dikwe, which serves the dual purpose of safeguarding coastlines as well as generating clean energy.
Dikwe is designed to be an ‘energy-positive’ breakwater system. Large vessels parked in the shallow waters of harbors need protection from powerful waves. Similarly, coastlines undergo constant erosion and need to be protected as infrastructure is built close to them. Breakwaters are manmade structures that protect against currents and tide surges. These structures have been built since antiquity, but have always served a single purpose. With Dikwe, researchers have added a low-carbon energy generation system to the breakwater, making it energy-positive. The energy generation system comprises a flap that oscillates with the incoming waves. The flap is connected to an energy capture device that converts wave energy into electricity. The concept was first developed at ifremer, the French institute for marine research and then developed over a decade to reach its full-scale demonstrator level.
In 2012, GEPS Techno approached Ifremer for its expertise in marine research to develop an energy-generating device that does not harm the marine ecosystem. With technical input from Ifremer, GEPS Techno first developed the Dikwe energy harvester concept digitally before hitting the waters with a prototype. The first tests were carried out with a 1/15th scale prototype at Ifremer’s Deep Wave test facility in Brest; over the years, the project was scaled up, and a 1/4th scale prototype at nearly 15 feet (4.5 m) was tested in July 2022, with Ifremer handling the wave measurements. Following the success of the tests, Legendre Group teamed up with GEPS Techno in a joint venture dubbed Wave-Op that works to use port infrastructure to generate energy as well. “This strategic entity aims to develop solutions that protect coastlines while recovering wave energy,” the joint venture said in a press release. “It will be a central player in the deployment of Dikwe technology on port breakwaters while paving the way for new applications.” Legendre Group is now constructing a full-scale technology demonstrator in Boulogne-sur-Mer in northern France. “This demonstrator serves as a tangible example of a new generation of energy-producing port infrastructure.”
“The screw-like design of the tidal energy generator”
ARCHIMEDES SCREW
https://interestingengineering.com/energy/screw-like-tidal-energy-generator-uk
Screw-like tidal power generator made from plastic trash
by Ameya Paleja / May 31, 2025
“Spiralis Energy, a London-based startup, wants to trial a screw-like tidal power generator and has bid with the States of Alderney in the English Channel to test its setup. The energy generator is made from recycled plastic waste, making it an attractive option among renewable energy sources. With an increased demand for tapping into energy sources that do not result in carbon emissions, innovative technologies have started to emerge. Among these are ways to trap the energy of the tides, which has largely remained out of humanity’s reach. Unlike wind and solar energy, which are more predictable and easy to work with, tapping into tidal energy needs sophisticated equipment that can generate energy from the slightest motions of the waves. Interesting Engineering has previously reported on a wide range of tidal wave energy generator designs that aim to tap into this continuously available source. Still, a screw-like design has been a surprise for us, too.
Spiralis calls its tidal energy generator the Axial Skelter, and it consists of a large Archimedes screw that has been used in other power generators before. The team says that it has modified the screw by adding the aerofoils to the design. This has been done to increase the torque generated by the screw and is intended to deliver greater energy output from the system. Even though the screw needs to be submerged in the water, the power generation happens above the water in drier conditions, making it easier to work with. The screw design is modular and can be easily 3D printed at a location where facilities are available before shipping the generator to the site of installation. The team has ensured that the generator uses recycled plastic waste, helping address another concern. If case a portion of the screw breaks off during operation, the modular section can be removed and replaced with another 3D-printed modular component, making it easy to repair the generator, even if located in remote locations.
Spiralis has reportedly approached the States of Alderney, an Island in the Bailiwick of Guernsey, the northernmost of the Channel Islands. As per its proposal, the startup will test two Axial Skelters, each about 66 feet (20 m) long, during the winter months. As seen in the video above, the Axial Skelters will be mounted on floating platforms but are not looking to generate any power during these tests. Instead, the setup seeks to understand the tidal flow of Alderney waters in the colder months. The local government of Alderney is likely to charge Spiralis a small fee for using its waters for testing. If the testing is successful, Spiralis might also set up an office in the region and supply energy to the local grid at a discounted price. As per Spiralis’ website, Axial Skelter can deliver the lowest energy cost among other energy generation options worldwide. The company tested a prototype of its technology in May of this year, and its full-size generator has a power output of 500 kW at 3.5 m/s. If the tests go well, it could also put Alderney on the map for tidal energy testing sites, a promising way to harness clean energy.”
WAVE ENERGY CONVERTER
https://interestingengineering.com/water-pendulum-tech-wave-power
French startup wave energy tech turns sea motion into electricity
by Georgina Jedikovska / Jul 08, 2025
“A French wave energy company has secured a multi-million dollar funding round to advance its pioneering technology, aiming to deploy a full-scale demonstrator and fast-track international expansion. Bordeaux-based Seaturns raised USD 2.9 million (EUR 2.45 million) to advance and industrialize its wave energy technology. The round, which was conducted primarily via the climate tech investment platform Keenest, drew support from 1,543 individual backers and key institutional investors. “We warmly thank the 1,543 investors who have placed their trust in us,” Vincent Tournerie, founder and president of Seaturns, emphasized. “This support is critical for deploying our full-scale demonstrator and accelerating our industrial development.” According to officials, the support follows the company’s nearly decade-long effort to develop a patented wave energy solution designed for simplicity, resilience, and scalable production.
Seaturns’ breakthrough quarter-scale prototype recently completed 18 months of rigorous testing at Ifremer in Brest, France. It reportedly yielded promising results in both electricity generation and system durability. The SEM-REV site, operated by the OPEN-C Foundation, features subsea infrastructure, environmental monitoring systems, and technical support, all of which are resources designed to minimize industrial and environmental risks ahead of market deployment. Harnessing ocean wave motion to generate electricity, the technology features a cylindrical wave energy converter (WEC) that moves horizontally with the motion of ocean swells, a movement known as surge. Using a patented anchoring system, the device converts this surge into a pitching motion, enabling efficient energy capture.
Designed for cost efficiency, the WEC supports simplified offshore installation, low-maintenance operation, and reduced environmental impact. It aims to lower production and operating costs compared to conventional wave energy technologies. Inside the converter, a water pendulum and two air-filled chambers, positioned at the top and separated by a vertical axial divider, generate airflow through pressure cycles driven by the floater’s pitching motion. This airflow powers a turbine directly coupled to a generator, producing electricity.
“Seaturns’ wave energy tech combines performance, simplicity, and cost control”
The company stated that the funds raised will be allocated to three main strategic objectives, including deploying a full-scale demonstrator at the SEM-REV offshore test site in summer 2025, beginning industrial-scale production, and expanding commercialization efforts in global markets. Renan Labrunie, chief operating officer at Keenest, praised the technology’s impressive performance during trials that concluded in February 2025. “We are thrilled to support them in this new phase of development – this project we’ve been following for a long time, and it fits perfectly within our investment focus on climate and carbonization,” Labrunie said.
“I invested in Seaturns because we are developing a high-potential emerging technology for Europe’s energy mix,” Lawrence Sigaud, deputy CEO of Seaturns, said in a press release. “We are providing a concrete solution to decarbonization challenges and actively preparing for industrial scale-up.” Seaturns initiated a fundraising campaign to advance its wave power technology following years of research, development, and testing earlier this year. It then signed an agreement with Fondation OPEN-C to deploy a full-scale demonstrator at the SEM-REV offshore test site near Le Croisic, with installation planned for summer 2025. Apart from Open‑C, its main partners include Bpifrance, Horizon Europe, i‑Nov, Nouvelle‑Aquitaine, and Ifremer.”
PREVIOUSLY
TIDAL POWER
https://spectrevision.net/2007/10/20/tidal-power/
OCEAN POWER
https://spectrevision.net/2014/04/18/ocean-power/
RAIN POWERED
https://spectrevision.net/2016/04/29/rain-powered/
SOLARPUNK
https://spectrevision.net/2020/10/08/solarpunk/
OSMOTIC POWER
https://spectrevision.net/2023/07/04/hygroelectricity/
RAIN POWER (cont.)
https://spectrevision.net/2025/04/23/rain-power/