New offshore solar testing results to pave way for certification standards

A new white paper released under the North Sea Two (NS2) project outlines important findings from full-scale testing of floating offshore solar systems under simulated North Sea wave conditions. Conducted in the Deltares Delta Flume, the tests were a joint effort by Oceans of Energy, Deltares, TNO, and DNV.

According to Deltares, the research offers structural validation for floating solar modules deployed at seawater level and delivers recommendations for establishing certification processes in the offshore solar sector.

“The Delta Flume tests have provided useful insights into the behaviour of the floating system and individual components under severe wave loads,” said Roderik Hoekstra, Deltares Project Lead.

Despite growing interest in offshore solar as a complementary technology to offshore wind, no standardized testing or certification framework is in place, the company said. The NS2 project aims to address this gap by generating evidence through field operations and lab simulations. 

According to Deltares, certification is essential for enabling long-term, cost-effective deployment in harsh marine environments.

The Delta Flume experiments evaluated wave loads on several floating platforms from Oceans of Energy under controlled but realistic offshore conditions. Researchers focused on the mechanical response of the PV modules and overall system dynamics.

“The NS2 Delta Flume tests have greatly increased our understanding of how our offshore solar systems surpass the high waves in the offshore North Sea environment. This collaboration together is of large importance in making progress towards certification of offshore solar,” said Fabian Koppes, Head of Product, Oceans of Energy.

Koppes also noted that knowledge from these tests informed Oceans of Energy’s recent system installation within the CrossWind Hollandse Kust Noord offshore wind farm in summer 2025.

The program combined small- and proto-scale tests. While small-scale models help identify core mechanical mechanisms, proto-scale testing enabled detailed force measurements on individual components, essential for accurate structural modelling.

“This gave DNV a better understanding of the structural and mechanical requirements of these systems. It highlighted how testing activities contribute to the development of offshore solar certification,” added DNV.

DNV specialists were invited to witness the full-scale testing, with data captured across varying floater lengths and wave conditions.

“TNO is happy that we have contributed to this collaborative experiment in a unique experimental testing environment to validate hydrodynamic models and assess the impact of waves on solar panels,” said Jan Kroon, TNO Project Lead.

The findings are published in the white paper “The Structural Testing of Offshore Solar Systems and PV-Modules by wave slamming in the Deltares Delta Flume.” It outlines the methodology, experimental results, and guidance for progressing towards certification.

“With the results and recommendations in the paper, policymakers and industry can take the next steps towards certification, thereby bringing the potential offered by offshore solar energy a step closer to reality,” Deltares said.

The NS2 project is funded by the Dutch Ministry of Economic Affairs and includes a four-year offshore pilot and controlled laboratory tests. Partners include Oceans of Energy, Deltares, DNV, and TNO.

In May, offshore installation works were completed for the anchoring system of the first offshore solar farm that is to be installed within the Hollandse Kust Noord (HKN) offshore wind farm, according to Oceans of Energy.

In December 2024, Deltares supported the Hague-based Wave Energy Collective (Weco) in achieving first power with its Kaizen wave energy converter (WEC). The collaboration also enabled further design validation and optimisation of the device.