New tech from two Scandinavian firms to cut wave energy converter cost and mass

Swedish company CorPower Ocean and Norway-based OPS Solutions have developed a pre-tension cylinder (PTC) prototype, marking a step toward reducing the cost and mass of wave energy converters (WECs). 

The two companies teamed up through the COMPACT project, combining expertise in wave energy and offshore fabrication. CorPower Ocean said the project focused on developing a lightweight pressure casing that could slash production costs and improve performance.

By utilizing low-cost composite designs and offshore manufacturing techniques, CorPower Ocean said that the new approach could increase efficiency in WEC systems while reducing overall energy generation costs.

According to CorPower Ocean, the project is focused on the development, testing, and certification of the PTC cylinder, a key component of its WEC system. The resulting design could have an impact on wave energy commercialization, the Swedish company noted.

CorPower Ocean Senior Technical Project Manager and COMPACT Project Lead Ross Harnden confirmed the success of the initial burst test, which saw the cylinder reach nearly 700 bar, which is 2.3 times the maximum operating pressure.

“This validates the COMPACT cylinder design philosophy,” Harnden said. 

“With small modifications to the composite layup, it is expected that it will be possible to reach the 900 bar required to obtain PED certification of the design, which is required for type certification. The results from the COMPACT project will now be fed into future design iterations of the CorPower Ocean WEC and contribute to bringing viable wave energy to market.”

A key challenge during the project was finding a suitable cylinder liner material, the company said. Testing various polymer combinations revealed limited cost-effective solutions that could meet the required pressure and temperature conditions. CorPower Ocean said that further research, potentially involving external institutes, will focus on solving this issue.

OPS Composite Solutions General Manager Reidar Anderssen added: “We’re thrilled with the outcome of the COMPACT Project delivered in partnership with CorPower Ocean. By combining our areas of expertise we have been able to drive real industry advances taking wave energy ever closer to commercialisation.”

The project received financial backing from Iceland, Liechtenstein, and Norway under the EEA Grants “Blue Growth Programme,” which supports innovations in the blue economy. 

According to CorPower Ocean, the COMPACT Project aligns with Portugal’s industrial strategy for ocean renewable energies, which estimates that ocean renewable energy could supply 25% of the country’s annual power consumption and create economic benefits, including €254 million in investment and 1,500 new jobs.

The project’s key developments include advancements in PTC cylinder manufacturing, which is planned to be used in CorPower Ocean’s next-gen C5 device, improved winding and flange connection techniques, and strategies to minimize bolt fatigue. Additionally, new insights were gained from testing fabric-backed high-density poly ethylene (HDPE) as a liner material, which could shape future WEC iterations.

In December 2024, CorPower Ocean’s wave energy initiative in Portugal secured backing from the European Investment Bank (EIB), which described the project as an “innovative solution that could revolutionize the renewable energy landscape.”