Optima Projects is a specialist engineering and design consultancy, who are currently developing a pioneering range of cruising boats, setting a new standard for sustainability at sea, powered by electric propulsion for RCD Cat B, Offshore rating.
The innovative and highly efficient hull form will give exceptional comfort, stability and safety with semi displacement performance. With a pleasantly quiet cruising speed of 14 knots, the propulsion from its high-performance twin electric drives provides a sustainable alternative to conventional motor yachts using fossil fuels. The significantly reduced energy consumption compared to conventional boats, ensures the boat is capable of motoring all day, at a very comfortable 8 knots, before charging overnight on standard shore-power. The boat is also capable of extended ranges of over 100 miles and will be self-sufficient for weeks away from shore-power using a combination of integrated solar PV charging, a small diesel generator or hydrogen fuel cell.
Cape Horn Engineering were proudly commissioned for their marine expertise and CFD technology to advance this exciting design project, where minimal environmental impact, performance and sustainability were key priorities.
To ensure the highest levels of efficiency and performance were achieved an extensive programme of CFD simulations and analysis in calm water and in waves was undertaken. The design optimisation considered several hull candidates with various distances between the main hull and side hulls, hull volume distribution and the exact position of spray rails to minimise resistance and optimise hull wake interactions.
The seakeeping simulations were performed for different boat speeds and in waves of different height, direction and frequencies. The resulting accelerations, loads and added resistance were compared for the different configurations to maximise the efficiency and to allow efficient operation above conventional displacement speeds. It was also demonstrated that the hull will avoid the harsh accelerations associated with conventional planing hulls improving passenger comfort and safety. As some motorboats can struggle with control running down oblique waves, especially when the waves overtake the vessel, numerous sea-states were investigated to prove that the ultra-low resistance hull could easily accommodate these situations. Foil assistance for reducing drag and motions in waves was also investigated in further studies for possible consideration.
This electric cruising boat design will help create a much more sustainable leisure marine industry with a significantly lower cost of ownership and very low environmental impact. At 11m hull length and 3.7m beam, it has a spacious cockpit, an optional hard top, two double cabins, heads and a fully equipped galley. This cutting edge design is planned for build in the UK, later this year with further models already scheduled.
David Kendall, MD at Optima Projects commented “It has been wonderful to work with Rodrigo and his team of CFD analysts at Cape Horn Engineering, who have been very flexible in their approach, adapting the scope of work depending on the results of each analysis. This enabled a higher degree of optimisation than would be possible through tank testing with a similar budget.”
This work has been supported by Innovate UK via the Sustainable Innovation Fund. For more details view: