Lagoon 51 – 3020Wp SP series

Launched in 2022, the Lagoon 51 catamaran is equipped with a bespoke 3,020Wp solar array. The walkable panels were designed for the anticipated shade and provide enough energy to run all electrical systems on board self-sufficiently. For the successful collaboration between shipyard and our design team, she is currently among the three finalists for the Boatbuilder Awards.


Modern 3D CAD – systems not only allow the adjustment to complex contours, they also let the shipyard and designer experience the visual appearance of the system before installation. In an intensive exchange with Lagoon Catamarans, surfaces on the saloon superstructure were selected to be fitted with solar panels.

Based on the 3D model, these were examined for double curvatures. The remaining areas were used to create the contours of the solar array, taking into account the shadow sources on board and the styling of the catamaran.

79 panel-integrated bypass diodes, optimized string layouts and 14 separate MPP control circuits were implemented for maximum shade tolerance. The bypass diodes bridge shaded areas of the solar array and, in combination with the MPPT controllers, ensure that the array delivers the best possible energy yield even in difficult lighting conditions.

Verification – 1:1 paper templates

After approval of the 3D renderings by the shipyard, the entire system was plotted in paper form to be tested on board the first Lagoon 51. This reveals potential problems that may be overlooked in a purely digital design process. In addition, the paper templates allow the visual impression of the system to be experienced in real terms for the first time.

After incorporating the resulting corrections (cable positions and various changes to the panel outlines), the system was ready to be put into production.


Solbian’s proprietary wiring solution on the backside of the panels with optimized cable positions enables fast and uncomplicated installation. All wires are routed below deck invisibly and watertight directly beneath the panels, where they are connected in series in the individual control circuits and routed to the MPPT controller.

The textured surface is not only particularly durable, it also ensures that the deck surfaces are always slip-free and safe to walk on with boat shoes, even when wet. The black base laminate in combination with concealed conductive circuits results in a homogeneous color of the system with barely visible solar cells.

Self-sufficient energy supply, perfectly integrated

The finished solar system not only fits perfectly into the design of the Lagoon 51, it also makes optimal use of all surfaces without restricting the crew when sailing the catamaran. With 3,020Wp it delivers approx. 12-18kWh (900-1,400Ah @13V) each day, which in combination with the lithium battery is sufficient for the operation of all electrical consumers on board – including several hours of air conditioning. 

The 618Wp system on the hardtop already provides enough energy to run the usual consumers of a catamaran of this size (lighting, navigation, autopilot, coffee machine, music, …) self-sufficiently on most days.

Due to the low weight of the system – the solar panels weigh less than 38kg, the whole system incl. controller and cables below 70kg – the sailing characteristics and the center of gravity of the yacht are not affected, furthermore no reinforcements of the structure are necessary.

Technical data:
Power: 3,020Wp
Panel series: SP
Weight: 38kg
Battery voltage: 12V
Battery type: LiFePO4

Photos: © Lagoon CatamaransGilles Martin-Raget