Spanish scientists, led by the University of Oviedo, have introduced a groundbreaking offshore floating photovoltaic (PV) system called HelioSea. The system uniquely combines a dual-axis solar tracker with a mini tension leg platform (TLP), presenting a novel solution for harnessing solar energy in challenging marine environments.

At the heart of HelioSea is the tension leg platform, a structure known for its stability in offshore drilling platforms. The TLP comprises a buoyant hull, vertical cylindrical columns, submerged horizontal pontoons, and tubular member bracing. Taut tendons or tethers vertically moor the platform, ensuring structural stability in the dynamic marine environment.

Designed to withstand erosion, abrasion, UV-induced deterioration, temperature fluctuations, humidity, and saltwater corrosion, the TLP incorporates a robust dual-layer protective system via hot-dip galvanization. This design ensures durability and reliability in harsh offshore conditions.

The HelioSea prototype, with a 75 kW capacity, hosts 138 bifacial PV panels strategically arranged on a top-of-pole mount. Vertical and horizontal dual-axis trackers automatically adjust panel angles throughout the day, optimizing energy capture in offshore environments.

A notable feature is the system's modular design, allowing separate assembly of the TLP and top-of-pole mount, facilitating easy transport offshore. The reduced dimensions enable shipping on a small barge, adding flexibility to deployment strategies.

HelioSea boasts a capacity density of 64 MW/km2 and a competitive levelized cost of energy (LCOE) ranging from €0.16 to €0.27/kWh. These metrics align with offshore floating wind systems and surpass other marine renewable energies, making HelioSea a promising contender in the renewable energy landscape.

Currently in the early stages of development with a Technology Readiness Level (TRL) of 3, HelioSea has undergone wave tank testing to confirm stability and structural verification. As the concept advances, the TRL is expected to increase, moving HelioSea closer to full commercial application.

Based on: https://www.pv-magazine.com