Marine energy developers have often faced a choice between two very different approaches to placing their technology in the water. One option is to fix the system to the seabed. The other is to mount it on a floating platform at the surface. Each approach comes with its own engineering challenges and environmental considerations.
In recent years, the advantages of surface-mounted platforms have become more widely recognized. Independent assessments and real-world trials have highlighted how floating designs can reduce costs, simplify maintenance, and open new opportunities for clean energy production in both tidal and river environments.
Lower Costs in Construction and Operation
A fixed installation typically requires heavy subsea construction and specialized vessels, for deployment. These activities drive up capital costs and can delay project timelines. A floating platform, by contrast, can be built using simple hull designs such as barges and can be assembled and tested in a shipyard before deployment.
Ray Hunter, Director at Uaine Gorm Power Associates, notes that the host vessel in this type of system can be far less expensive than complex contoured units designed for fixed installations. This reduced complexity is not only easier on budgets but also shortens the time needed to get from design to deployment.
Easier Access for Maintenance
Maintenance is a significant driver of lifetime costs for marine energy projects. In fixed seabed systems, even simple repairs may require divers, remotely operated vehicles, or large lift vessels. Deployment in strong tidal streams means only short time windows (slack water) are open to conduct work underwater safely. A surface-mounted platform changes that equation.
Because the primary components are accessible from above, technicians can carry out inspections, part replacements, and even turbine servicing using small service boats. Hunter emphasizes that most maintenance tasks can be performed quickly and at low cost without removing the system from the site. This ease of access improves uptime and allows operators to respond promptly to any performance issues.
Improved Survivability and Reliability
The marine environment can be harsh, with strong currents, storms, and debris posing constant threats. Floating systems can incorporate features such as hinged mounting arms, articulated joints, and flexible mooring arrangements that allow them to ride out extreme conditions without damage.
The Offshore Renewable Energy Catapult Technology and Research Innovation Centre has reported that placing the power take-off equipment above the surface reduces exposure to saltwater corrosion and simplifies the protection of electrical systems. By reducing the risk of damage and making repairs more straightforward, surface-mounted designs can deliver higher reliability over the life of the project.
Adaptability to Different Sites
Fixed seabed devices often require specific depth and seabed conditions. In contrast, a floating platform can be adapted to a variety of depths and can be relocated if conditions change or if a more productive site becomes available. This flexibility allows project developers to respond to environmental studies, permitting requirements, or evolving energy needs without starting from scratch.
In the case of the Archimedes screw turbine, the low impact of the floating arrangement allows for installation in sensitive habitats while avoiding disturbance to the seabed.
Expanding the Role of Floating Marine Energy
Surface-mounted platforms are proving that marine energy does not have to be locked into one approach. By addressing the cost, maintenance, and environmental challenges that have slowed the sector in the past, they are helping to bring more projects from concept to reality.
For communities seeking clean, predictable, and locally produced power, floating marine energy systems offer a promising and practical path forward. With continued testing and refinement, they can play a central role in making marine energy a dependable part of the global renewable mix.
