Wattlab Proves Viability and Scalability of Solar Power for Bulk Carriers with Solar Flatrack

Following successful pilot projects and the first full-scale installation on the seagoing vessel Vertom Tula, Wattlab is now advancing its Solar Flatrack solution for the international bulk shipping market. Currently, Solar Flatracks can be deployed on vessels up to the Supramax segment. In parallel, Wattlab has begun developing seaworthy solar solutions for Panamax and even Capesize bulk carriers

Dutch maritime solar technology company Wattlab, a specialist in solar power for shipping, has demonstrated through the successful deployment of its Solar Flatrack system that solar energy can be a practical and scalable component of onboard energy supply, particularly for a vessel’s hotel load. Results from two pilot projects and the first full-scale installation on a coaster confirm that the system performs reliably at sea while directly contributing to fuel savings and emission reductions.

From Pilot to Practice

In collaboration with TNO and shipping company Vertom, Wattlab first tested the system on the Vertom Anette. Insights gained from this trial were applied to the Vertom Tula, where 44 Solar Flatracks now reduce approximately 20% of the onboard hotel load. The project received co-financing from the European Union’s Just Transition Fund (JTF), part of the European Green Deal aimed at achieving climate neutrality by 2050.

Bo Salet, CEO and co-founder of Wattlab, stated:

“With this step, solar power at sea is no longer an experiment, but a working solution. The pilot projects provided crucial lessons on usability, technical performance, crew operation, and seaworthiness. This knowledge has significantly upgraded the Solar Flatrack system.”

No Impact on Operations

A key concern for shipowners is the effect of solar installations on daily operations, especially during deck cargo handling. Wattlab’s Solar Flatrack system is designed to ensure that:

• Panels can remain in place during loading and unloading.

• The system can be easily disconnected and stacked if necessary.

• Units can be compactly stored within the footprint of a single 20-foot container.

These features ensure that vessels maintain full operational flexibility.

Scaling Towards Larger Bulk Carriers

With current technology, Wattlab can deploy solar systems on coasters and vessels up to the Supramax segment, particularly on ships with foldable or stackable hatch covers. Based on these results, development is underway for larger vessel classes, including Panamax and bigger bulk carriers.

Salet added:

“Market interest is growing rapidly. We have already engaged with more than 200 international parties interested in applying Solar Flatracks across their fleets.”

Supporting Energy Transition and Regulatory Compliance

By reducing fuel consumption, solar energy directly lowers CO₂ emissions and enhances performance metrics such as CII and EEXI. The technology also supports compliance with European regulations, including FuelEU Maritime and the EU ETS, while reducing shipowners’ exposure to volatile fuel prices.

With an expected return on investment of 3 to 5 years, Wattlab positions Solar Flatracks as a financially viable solution for decarbonizing both existing and new vessels.