Wattlab Launches SolarDeck: Plug-and-Play Solar Power for Seagoing Vessels

Wattlab, a Dutch specialist in maritime solar technology, has introduced its new SolarDeck system to the seagoing shipping market. SolarDeck features modular, deck-mounted solar panels that help reduce fuel consumption and CO₂ emissions, with an estimated return on investment of 3–5 years. Installed on a seagoing general cargo vessel, it also offers substantial financial advantages under the Fuel EU Maritime and EU ETS regulations.

Since its founding in 2017, Wattlab has focused on inland shipping with its Solar Flatrack system—modular, stackable panels with integrated inverters—used on over 25 vessels. Now, aiming to lower fuel costs and support maritime decarbonization, the company is moving into the seagoing sector with SolarDeck.

“At all times during the design of SolarDeck, we prioritised the shipowner’s requirements. We know that ‘time is money’. That’s why the SolarDeck can be installed in a minimum amount of time using container twist lock fittings. It also does not impact normal loading and unloading procedures,” says Wattlab CEO Bo Salet. “However, we also know – for cargo shipowners especially – that ‘space is money’. In the event of a deck load such as offshore wind blades, the ship’s crew can store the SolarDeck inside the volume of a 20-foot container, thus freeing up the deck for cargo.”

Development and Testing

Developed in collaboration with TNO (the Netherlands Organisation for Applied Scientific Research) and international shipping firm Vertom, SolarDeck has undergone 18 months of testing aboard Vertom’s 7,280dwt dry cargo vessel Anette. The project was co-financed by the EU’s Just Transition Fund. The tests confirmed SolarDeck’s durability and effectiveness in maritime conditions.

“The test results show that SolarDeck performs well in the tougher environment – in terms of salinity and rougher sea states – of coastal shipping. Because salt water can drain freely from the solar panels, there’s no chance of a salt crust forming. As such, SolarDeck generates the expected power output levels,” Salet explains. “Furthermore, the system is robust enough to withstand storms as well as the usual day-to-day activities on board a seagoing cargo ship – while staying safe at all times.”

Impact and Savings

On a 119-meter-long and 14-meter-wide vessel like Anette, SolarDeck is expected to cut 20 metric tons of fuel and 68 metric tons of CO₂ emissions annually. These reductions also improve EEXI and CII scores, and for larger ships, the benefits scale accordingly.

“We are excited to introduce SolarDeck to the seagoing shipping industry – to show shipowners what this system can mean to their operations,” Salet concludes. “SolarDeck isn’t just a green upgrade. With a return on investment of 3 to 5 years, it’s a smart investment.”

EU Support

The SolarDeck pilot has been supported by the European Union’s Just Transition Fund, part of the EU Green Deal’s broader goal of reaching climate neutrality by 2050.