For engineers looking to install solar farms in the ocean, there are many obstacles to consider, from saltwater corrosion and rough seas to safe mooring and difficult maintenance. The humble barnacle can also prove a major challenge. Indeed, a solar farm installed in Singapore’s Johor Strait, near the town of Woodlands, was hampered by barnacles that attached themselves to the floating pontoons supporting the solar panels, adding significant weight and reducing the solar farm’s overall buoyancy, according to environmental news site The Pulse.
Singapore is turning to offshore solar for the obvious reason that it simply does not have enough land for large-scale solar farms. Completed in March 2021, the 5 MW Woodlands Solar Farm has 13,312 solar panels mounted on more than 30,000 floats and covers approximately 12 acres. The system has been carefully designed for marine conditions, with a constant tension mooring system to keep the array stable in waves and currents. It is built to produce around 6 million kWh of electricity per year and avoid around 4,258 tonnes of carbon dioxide emissions.
The developers of the facility were always aware of the risk of disruption to marine life, with barnacles specifically identified as one of the challenges of the seawater-based project. The engineers also knew that other marine growths, such as algae and mussels, would be a problem and so set about designing and testing the system accordingly. The challenge now is to find a cost-effective way to control this growth over the coming years.
Preventing marine growth from solar farms
Preventing marine growth in solar farms may involve regular inspections and cleaning, as well as the use of designs and surface coatings to discourage organisms from colonizing the pontoons. Another idea is to integrate monitoring systems that can track changes in the weight and buoyancy of floating platforms, giving operators an early warning if barnacles and other marine life begin to have a negative effect on the condition of the installation.
Saltwater corrosion, on the other hand, is a marine challenge that engineers have already found ways to manage. For example, researchers found that modified epoxy and graphene-zinc coatings continued to provide good protection after 18 months in ocean water. Unlike corrosion, which can be effectively combatted using protective coatings and other engineering measures, marine growth cannot be avoided as easily. It can and will likely continue to come back, meaning floating solar farm operators will need to factor it into the installation’s ongoing maintenance schedule after it comes online. The hard truth is that if the problem becomes too costly to control, it risks undermining the benefits of offshore power generation.
The presence of marine life does not always have to be a problem for floating solar farms, as demonstrated by a floating solar farm in the Netherlands, which benefits the underwater ecosystem without interfering with the operation of the installation. Likewise, terrestrial solar farms can also have a positive effect on local wildlife.
The world’s largest open water solar farm doesn’t actually float
Unlike the one in the Strait of Johor, Singapore’s largest floating solar farm does not face the same challenges as it sits on a freshwater reservoir. The Tengeh Floating Solar Farm opened in 2021, with a 60 MWp installation comprising more than 122,000 solar panels covering approximately 111 acres. But freshwater solar farms can still experience organic growth and therefore need to be regularly inspected and cleaned.
The world’s largest deep-sea solar farm in terms of production capacity is currently in China, a world leader in the development of offshore wind farms. But above all, it is not a floating installation. Fully connected to the grid in December 2025, the 1GW HG14 project off Dongying, about 200 miles southeast of Beijing, includes thousands of solar panels mounted on steel platforms attached to the seabed, placing the panels above the water rather than on it. This gives it a significant advantage over floating solar installations in that, although marine life can still attach to the structure, the added weight does not drag the solar panels lower into the water.
As for floating Offshore solar installations, the largest in terms of production capacity are currently in Taiwan. The Changhua complex has a capacity of approximately 440 MW and covers 857 acres, an area larger than New York’s Central Park. As expected, the project faces many of the same challenges as the Singapore farm, including salt water, marine life, tides, debris, waves and high winds.
