Retrofitting for Tomorrow: The Challenges & Opportunities of Greening Existing Superyachts

Monaco, SEPTEMBER 19th 2025

As the superyacht sector begins its path towards decarbonisation, early sustainable innovation has tended to focus on pioneering new-build projects. However, as environmental regulations tighten and charter clients increasingly favour more sustainable vessels, retrofitting the existing fleet of 6000 superyachts will become essential. With over 80% of today’s global fleet expected to still be in operation by 2030, new builds alone can’t deliver the sector’s decarbonisation goals.

The market is paying attention, with shipbuilder initiatives such as MB92’s “Refit for the Future” gaining traction, signaling a clear shift in expectations and operational norms.

At SEA Index, we believe in meaningful progress: action that is measurable, data-driven, and aligned with the realities of owners, captains, and shipyards. We therefore see retrofitting as a critical piece of the responsible yachting puzzle.

The Business Case: Retrofitting is Rising

Retrofitting isn’t just an opportunity to reduce a yacht’s environmental impact, it makes financial and strategic sense. Modernisation improves compliance readiness, helps maintain or enhance asset value, and increases appeal in the charter market. It can also reduce operational costs through greater efficiency, particularly when it comes to fuel use.

As the industry moves toward more transparent impact reporting, the hidden costs of unsustainable yachting, both reputational and financial, are coming into sharper focus. Owners who act now stand to benefit from an early mover advantage.

La Ciotat Shipyard

La Ciotat Shipyards

Shipyard Practices: Refit Facilities Get Greener

When thinking about retrofitting (or any form of ship building), it’s vital to think beyond the vessel itself. Sustainability doesn’t end with the yacht, it extends to the shipyards performing the work. Forward-looking refit shipyards like MB92 and Monaco Marine (a group of shipyards) are investing in greener infrastructure, including improved waste management systems, renewable energy use, and digitalisation to track environmental impact.

Why is Retrofitting Complex?

Despite the clear benefits, retrofitting is not without its challenges. Most superyachts were not originally designed with sustainability in mind. Constraints like limited engine room space, weight distribution, and hull design complicate upgrades, particularly for propulsion and energy systems. While some improvements, such as LED lighting or insulation, are relatively straightforward, others require significant reengineering and investment. Downtime, integration issues, and technology compatibility are all considerations.

What Can Be Upgraded Today?

The 14th La Belle Classe Superyachts Business Symposium, hosted by the Yacht Club de Monaco and Credit Suisse (now UBS group), brought together 60 industry experts and yacht owners to discuss the pressing need to retrofit the ageing superyacht fleet. Michel Buffat, now an emeritus committee member of the SEA Index, emphasised that meaningful emission reductions will only come from transforming the existing fleet, which now averages 23 years old. Practical retrofit strategies, including switching to biofuels, upgrading generators, using low-impact materials, and improving energy efficiency through lighting, HVAC, and alternative decking solutions must form part of the solutions.

There is no one-size-fits-all retrofit strategy, but several upgrade pathways are becoming standard:

  • Propulsion: Hybrid systems and exhaust treatment solutions
  • Energy systems: Battery storage for hotel load and engine support
  • Efficiency: HVAC and insulation upgrades, LED lighting
  • Software: Onboard energy management platforms
  • Noise mitigation: Underwater Radiated Noise (URN) technology

Across the sector, builders and yards are increasingly prioritising sustainability in their retrofits, often working closely with owners to align on long-term environmental goals with business needs.

“In our retrofitting projects, we often implement changes ranging from upgrading onboard lighting systems to swapping out older air conditioning units for high-efficiency screw-type compressors, where smart ventilation controls are increasingly integrated to improve comfort and optimize energy use. The installation or upgrade of battery banks is also a growing trend. Looking ahead, we believe that hybrid and diesel-electric propulsion systems—combined with advanced thrusters—represent the future of efficient and comfortable yachting.”
(Ivaylo Nenov, Technical Manager Y.CO).

Where to start with retrofitting?

SEA Index can help owners navigate the complexity of retrofitting.

The CO2 Certification assessment framework helps owners understand their vessel’s current impact and identify upgrade options that can significantly improve performance through an ‘Options for Improvements’ Document. This ensures superyacht upgrades are not just well-intentioned, but verifiable and backed by data.

Retrofitting is a long-term investment in the relevance, efficiency, and appeal of a superyacht. For owners and shipyards willing to act, it’s an opportunity to lead with credibility and integrity.
SEA Index is here to support you on that journey, from baseline measurement to certification, so you can move forward with confidence.

References

To find out more, get in touch with our team, start the SEA Index certification process and your sustainability journey now!

Share this article:

Related Articles

The SEA Index international network is growing - Read our latest news!