The design of REF – Renewable Energy Foiler – has now been revealed by Swiss Solar Boat, and SumToZero is extremely proud to be part of the sponsors of this talented and innovative student team.
Created in 2019, the Swiss Solar Boat association from EPFL first designed and built an innovative asymmetric one-seater boat, the Dahu. Equipped with solar panels and a hydrogen fuel cell, the vessel successfully completed the Lausanne Evian Crossing on April 30th, 2024.
![Dahu SwissSolarBoat Lac Leman crossing](https://sumtozero.com/wp-content/uploads/2024/06/SwissSolarBoatDahu-1024x644.jpeg)
Willing to explore and provide technological solutions to the challenge of sustainable alternatives to large-scale mobilities, Swiss Solar Boat has embarked on the building of a new foiling vessel, equipped with an hybrid solar-green hydrogen propulsion system. Driven by the objective to suggest low-carbon alternatives, the dynamic student team also strives to reduce the carbon footprint during production phase. Notably, to avoid the use of carbon moulds, they have chosen to build the hull of the REF (Renewable Energy Foiler) using an innovative carbon-wood-carbon “sandwich” structure.
With a cruise speed of 25kts and a top speed of 35kts, the 3-seats foiling boat will have one T-rudder and a front Pi-foil with mounted propellers. With one actuator on top of each front strut, the whole Pi-foil is designed to rake during take-off and then to be stable during flight. Trim and heave will be controlled with rudder elevator flaps, while port and starboard flaps on the front gantry will be actuated at high frequency to control heel (as well as heave to a lower extent). Gomboc has proven to be an effective tool to the Swiss Solar Boat team and is currently used to assist the development of the flight control system.
The REF design is now officially revealed and its key aspects are shown in this video. The goal of the Swiss Solar Boat is now to complete the tour of Lac Léman (150km) in 2026.
![SwissSolarBoat REF Gantry](https://sumtozero.com/wp-content/uploads/2024/06/SwissSolarBoatREF_portique-1024x576.png)