Is Seawolf X Leading The Way In Superyacht Sustainability?

Yachting and sustainability aren’t natural bedfellows, but Seawolf X – the very first hybrid-electric yacht in Cecil Wright’s world-class fleet – is a compelling sign that change is afoot. Available to charter since 1 August, Seawolf X offers boaters the chance to travel without compromising on luxury or sustainability – a difficult feat on the seven seas.

So what are Seawolf X’s credentials, and can superyachts ever really be sustainable? C&TH picks the brains of the experts to find out.

Yachtbrokers can lead by example, but there needs to be legwork on the building side, too.

Inside Hybrid-Electric Superyacht Seawolf X

‘The simple truth is that without a healthy ecosystem, environment and ocean – which are the cornerstone stakeholders in yachting and the lifestyle it represents – the industry cannot exist.’ These are the words of Harrison MacManus, charter manager and one of Cecil Wright’s newer team members who is already thinking deeply about the role of yachtbrokers in the sustainability conversation.

‘We as managers and brokers are all aware of the carbon footprint yachting leaves behind,’ he tells me. ‘While brokers do not directly control the technology or operation of yachts, we play a leading role in shaping perception, influencing client behaviour and setting industry norms. Encouragingly, the new generation of brokers entering the industry are far more conscious of this responsibility than in the past. It may only be a small step, but it is a meaningful move in the right direction.’

Examples Harrison gives for best eco practice in yachting include designing routes to reduce fuel burn, sourcing local ingredients for meals cooked aboard and minimising single use plastic – but there’s a low sustainability ceiling aboard a gas-guzzler. So while brokers can ‘lead by example, embedding sustainability into central agency pitch packs, charter contracts and marketing guidelines’, as Harrison puts it, there needs to be some legwork on the building side, too.

Seawolf X can cruise on 100 percent electric power for a whole day.

This is where vessels like Seawolf X come in: best-in-class new builds that combine sustainability with the luxury experience. Measuring in at 140’6″, Seawolf X is a hybrid-electric charter yacht boasting cutting edge technology inspired by the oceans it sails on. Think ultra-efficient hydrodynamics (sea trials found the vessel’s stopping distance is often two, even three times further than an ordinary vessel), 1.5 megawatts of advanced battery storage (one of the largest in the superyachting world), solar panels you can walk over without noticing, a bespoke AI monitoring system developed over two years at the University of Pisa, and more. This all unites to allow Seawolf X to cruise on 100 percent electric power for a whole day, or on 90 percent for multiple days, all while hosting up to 12 guests. In fact, when Seawolf X is at full charge, she can sit at anchor running air conditioning, water heaters, playing music and having TVs on – anything and everything that makes her liveable – for days at a time without consuming any fuel.

As Cecil Wright partner Henry Smith puts it: ‘Seawolf X has set a new benchmark. Rossinavi’s BluE philosophy – marrying AI, electric propulsion and solar efficiency – is a model for future builds.’

Seawolf X is a true hybrid electric vessel.

She’s already very different to many hybrid yachts on the market, Seawolf X’s Captain Sean Rysenbry tells me: ‘She’s a true hybrid electric vessel. When I say “true”, I mean that a lot of vessels these days have auxiliary power propulsion made in addition to the traditional combustion engines, which is not quite the same. We actually don’t have engines. We have electric motors which are driven through the batteries or through the generators.’

This is one of the most noticeable differences between Seawolf X and her peers, Captain Sean tells me. Since there are no generators running, ‘it’s super peaceful’, he says. No humming, no smoke, no bubbling in the water – not even a vibration to let you know she’s alive. ‘The loudest thing you have, maybe, is the water lapping against the hull,’ Captain Sean says. ‘If you go to these beautiful little secluded bays, you could hear a pin drop throughout the night. We can be going 10 knots underway, and it feels like we’re not moving. It’s quite a bizarre sensation, I have to say. But our guests really love that, too. She has the fun, the feel and the essence of a sailing yacht but with the functionality of a motor yacht.’

She’s the dream vessel for eco-conscious brokers: ‘By spotlighting sustainable builds or refit projects in proposals and marketing, brokers can actively reward forward-thinking owners with consistent and repeat charter revenue,’ Harrison adds.

The AI system means you can see, at all times, which department or cabin is using the most power. (Master Suite)

But in this case, it all started with the owner. ‘The owning family is very engaged with the eco side of the vessel,’ Captain Sean tells me. ‘Superyachting has a pretty bad reputation for being a huge polluter. You know, these big 80 or 90 metre diesel guzzlers burning tens of thousands of litres of fuel per day, all for the sake of one couple on board, for example. People are really interested to see what yachting can be like if we’re not so irresponsible.’

Seawolf X’s AI system ‘analyses every single piece of machinery that we have on board’, Captain Sean explains, meaning he can see, at all times, which department or cabin is using the most power. This is used to correct overuse (if an oven is left on, for example) and to draw on the batteries in a more linear fashion to avoid surges (like scheduling laundry and cooking for different times). But, with a young and impressionable family of his own, the owner also uses this for educational purposes – something he calls the Green Challenge.

‘To be seen on a vessel like Seawolf X means you are promoting a path towards better responsibility.’

‘I mentioned that we have readings on the power usage of each cabin, so at the end of each week we create a leaderboard which shows which cabin is using the least energy – which cabin is winning,’ Captain Sean explains. ‘It’s a nice visual and makes learning about this kind of stuff fun and rewarding. So in an interesting way, even though most of the energy usage on board is managed by the crew, the owner found a way to let that mentality seep into the guests as well.’

As well as being privately owned, Seawolf X is available to charter via Cecil Wright, and its eco-credentials ‘are one of the highest selling points for the vessel’, Captain Sean says. Why? ‘Optics. It is a big thing for these people. And to be seen on a vessel like Seawolf X means you are promoting a path towards better responsibility.’

‘The owner found a way to make sustainability seep into the minds of his guests.’ (A Guest Cabin)

It’s a good time to be interested in sustainable yachting, with agenda-setting eco-advancements the topic du jour. ‘Rossinavi is developing a new concept called Solsea, also AI-powered and solar-integrated – capable of predicting guest needs and further minimising environmental footprint,’ Henry says. ‘Other builders are incorporating innovations like methanol fuel cells (e.g. Sanlorenzo), advanced solar skin systems (like Sunreef’s Solar Skin 3.0), and even wind-assisted propulsion. Plus, visionary projects like Earth 300 aim to launch mega‑yachts powered by green tech or even nuclear reactors to support oceanographic missions, further raising standards for clean maritime innovation – but this is a fair way off!’

But at least the seed has been sown – and Seawolf X proves sustainability can be sexy and satisfying without sacrifice. And that’s ‘one of the greatest things about this vessel’, Captain Sean says. ‘Most of the time when people associate sustainability and yachts, they think about sacrifice. What they have to sacrifice in order to be sustainable: you have a smaller boat, or lower range, or fewer amenities. But what this vessel shows is that not only can you have all of the above and more, you can also have a vessel that looks absolutely stunning.’

‘Luxury and responsibility: the two don’t need to be mutually exclusive.’ (Seawolf X’s onboard sauna)

Available to charter since summer 2025, Seawolf X is already an award winner, counting accolades like the Winner and Judges’ Commendation at the World Superyacht Awards 2025 and the International Yacht & Aviation Award for interior design. As Captain Sean puts it: ‘Luxury and responsibility: the two don’t need to be mutually exclusive.’

Meanwhile, as Seawolf X journeys around the world, she is piquing more and more interest. ‘A lot of people have been asking me a lot of questions about how they can try and introduce some of our practices onto their vessel,’ Captain Sean says. ‘If they can make any changes, how do I find the functionality – those kinds of things. My answer has always been: there’s absolutely no difference. Except, if anything, it’s just better.

‘I’m really proud to be leading this kind of project,’ Captain Sean says. ‘And I’m really not looking forward to the day I might have to go back to a normal boat.’

Seawolf X sleeps up to 12 guests and is available to charter from €380,000 per week, exclusively with Cecil Wright. cecilwright.com