The idea that superyachts by their nature cannot be sustainable is outdated. Engineering has moved on in leaps and bounds in the past few years alone and pioneering yachts like Black Pearl and Volpini 2 are proof that sustainable design doesn’t mean having to compromise on function or style. Speaking at the 2019 Superyacht Design Symposium, CEO of Silent Yachts Michael Köhler and Solar Cloth System president Alain Janet discuss the enormous potential of solar technology in yachting.
Michael Köhler calls himself “a reformed sailor” and has spent the last ten years developing a fleet of oceangoing solar-powered catamarans. Silent Yachts now have three models in production, the Silent 55, 64 and new 79 flagship. These eco-yachts are powered entirely by solar energy captured by extensive flybridge panelling, which is able to generate enough power to supply all the onboard hotel appliances as well as the propulsion.
Silent Yacht's 24 metre flagship has a top speed of 20 knots and is capable of travelling at 6-7 knots with unlimited range translating into more than 100 nautical miles per day (and zero emissions). Plus, with no engine room there is no noise, no vibrations, and much more usable space.
Köhler said, “What this represents to the yachtsman, among other features, is the ability to cruise for many hours at normal speed and throughout the entire day and evening at reduced speed. Silent Yachts sets the standard for an entirely new feeling in yachting: No fuel. No maintenance. Just pure solar-powered luxury.
“For 'normal average holiday usage' you'll have plenty of power without running the generator or with only running it one or two hours a day. If higher speeds are desired for a longer period of time the generator will supply the needed energy.”
Meanwhile, French sailmaker and Solar Cloth System founder Alain Janet is also paving the way for solar energy in yachting. His Solar Cloth is a lightweight film-like textile - as thin as a bank note and flexible enough to wrap round a pencil - which is able to generate electrical power.
“My aim was to have the lightest possible material in order to have the best ratio output vs weight. It’s been a long journey. It took us about three years to find the right recipe that meant longevity, output power and affordability.”
For sailing yachts the photovoltaic film can be laminated onto modern sail fabrics and is a smart solution to bulky panels. Alain Janet revealed the company is in the process of creating a Solar Cloth test sail for Oceanco’s trailblazing 106 metre Black Pearl. It was always the intention for the yacht’s DynaRig to have solar-sails but the technology was still being refined at the time of her launch last year.
The idea of a solar textile isn’t just restricted to sails. It can also be applied to awnings, Biminis and even catamaran trampolines. “We’re working on a trampoline for the multihulls, for the Daedalus 80. It’s a large and fairly unused surface which is horizontal on a boat and I believe it can produce some serious wattage,” explained Janet. Beyond yachting, the material is already being used in airships, greenhouses and even stratospheric balloons.
Janet and Köhler both agreed that, while solar energy is arguably the most reliable source of energy, a combination of power sources is the most realistic way of moving forward. "I do not believe there is one single solution" said Janet.
Michael Köhler believes a bigger generator should not be the default solution for more power. “I would like to ask the superyacht industry to review their current way of thinking to try to save energy. Don’t just go for the easy solution of installing a bigger generator. Think about how to reduce the overall power consumption in your boat, and then many other already existing solutions become viable."
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