The need for focus on energy reduction in the operational world of superyachting appears compelling when you consider a 65m yacht can consume as much energy as a small town with 900 houses. There is a widely discussed peak of inefficiency among vessels constructed in the first few years of this century when hotel loads were rising exponentially and the important measure of performance was top speed. The issue was dealt with at the time by the provision of generation and propulsion systems that, in practice, have often proven to be a mismatch to the operational profiles of the yachts. Plus, technology has moved on considerably since then.
The good news is that formally conducted energy audits of superyachts in service indicate there is significant potential for improvement across the fleet. A typical refit may result in a quantifiable 5%-10% energy saving – even from basic changes like switching to the most efficient antifouling and fine-tuning onboard systems settings and operations to ensure they are running at peak energy efficiency. Major refits might yield in the region of 25%-35% savings and for rebuild projects involving wholesale changes to the yacht and its systems and machinery that can be pushed as high as 50%. There are no shortages now of technical solutions to deliver those savings.
If pure fuel savings aren’t enough, there are several obvious side benefits to re-engining. Major overhauls on older engines may impact the time a superyacht has to stay in refit with increases in costs; whereas delivery of new engines can be timed to match the refit window. Improvements can simultaneously be sought in propeller efficiency and sound and vibration mitigation. Reduction in soot will result in less crew maintenance and improve the owner’s experience. And compliance to the latest IMO and EPA standards will help future proof against ever tightening regional and local demands.
If you take this a step further and look at the increasing number of hybrid installations occurring now across the superyacht sector, then you can tackle one of the most wasteful issues. Generators installed to service considerable house loads are often incorrectly load balanced; a suggestion from the panel was that generation plant onboard some of the global superyacht fleet may be running at as low as 20%-30% efficiency.
Most modern hybrid systems are now stepping well beyond their propulsion brief to use energy storage either to supplement or even completely replace one or more of the generators aboard. The aim being to get much more energy efficiency from every litre of diesel burned.
The first savings may well simply come from just changing the settings and use profile of the HVAC system. Beyond that, an investigation of the chiller, how advanced it is and whether replacement would yield gains, or considering transitioning from chilled water to direct expansion.
More substantial work might include changes to the ducts and airflow in the yacht, a source of potentially large gains. A lot of yachts dating back to around 2010 were designed to deliver high volumes of fresh air, which can lead to large energy losses. The hold-back on progress here being the difficulty of making changes without expensive disruption to expensive and complex interior fit-outs.
There may also be understandable reluctance too from yards in suggesting sustainable alternatives in the face of a precise refit brief driven by owners or their representatives. Classically trained salespeople know to address pain points presented by a customer and close the deal accordingly; it takes a braver person to suggest something that could be more expensive and less proven.
The panel universally agreed that sustainability may often be successfully driven through as an understood secondary benefit to primary priorities. Looking again at HVAC systems, another way to reduce power consumption is to improve shading or even reglaze with high technology solar controlled glass. Both initiatives can be hard to introduce with sustainability as the primary benefit. However, the owner may well be much more easily persuaded if a new set of awnings means greater comfort out on deck, or if the glazing is degraded or too transparent for his liking.
It’s a similar story with transom extensions. The growing trend for legacy superyachts to be lengthened aft is that this work provides scope for an improved swim platform or beach club, capacity for more toys or even some expanded space below deck. The sustainability gain however comes from improved hull efficiency, with a further bonus for the owner to consider that seakeeping may also be improved.
It’s important that these gains in environmental footprint are communicated well to the owner, irrespective of whether they were the original motive for authorising the work within a refit. Another important consideration is to have the refit planned as far in advance as possible, to maximise the possibility of incorporating more sustainable options within proposed solutions.
A further suggestion is to try and excite owners about the long-term potential they have in their yacht, or the one they're looking at buying. The proposal might even be a multi-year, multi-refit plan, with a lot of planning sat behind it. What you would then be selling is a controlled transition towards a future-proof yacht with the ultimate goals of each step mapped out.
Basic refits only are likely to impact value over coming years. If you are not making your yacht more sustainable over time it might be immaculate but is it becoming obsolete? The advent of emission regulations and other environmental regulations and protected areas could ultimately result in use of a beautifully maintained but older specification superyacht being constrained. There's an enormous amount of uncertainty around forthcoming regulations – by future proofing your yacht and upgrading it, you are hedging against uncertainty.
A vessel upgraded in refits to be more sustainable is not just an old yacht on the market. It's something which is still relevant, still looks cool, but has the appeal of more compliant and efficient operation. One which the children of owners’ will also be more comfortable with as they consider their own environmental impacts.
The good news is that formally conducted energy audits of superyachts in service indicate there is significant potential for improvement across the fleet. A typical refit may result in a quantifiable 5%-10% energy saving – even from basic changes like switching to the most efficient antifouling and fine-tuning onboard systems settings and operations to ensure they are running at peak energy efficiency. Major refits might yield in the region of 25%-35% savings and for rebuild projects involving wholesale changes to the yacht and its systems and machinery that can be pushed as high as 50%. There are no shortages now of technical solutions to deliver those savings.
Obvious wins from changing powerplants
Taking the most obvious target into account, upgrading propulsion engines may well yield discernible fuel savings over powerplants manufactured a decade or more ago. If you combine that with a more realistic take on the vessel’s service speed, confirmed by studying the data accumulated during years of years of use, then the use of smaller modern engines may well be considered appropriate. A superyacht’s top speed may well have only ever been called for at the helm during sea trials; cruising speeds are typically lower and on that basis a lower power output might be specified with no difference to the onboard experience other than less fuel stops and perhaps reduced noise and vibration too.If pure fuel savings aren’t enough, there are several obvious side benefits to re-engining. Major overhauls on older engines may impact the time a superyacht has to stay in refit with increases in costs; whereas delivery of new engines can be timed to match the refit window. Improvements can simultaneously be sought in propeller efficiency and sound and vibration mitigation. Reduction in soot will result in less crew maintenance and improve the owner’s experience. And compliance to the latest IMO and EPA standards will help future proof against ever tightening regional and local demands.
If you take this a step further and look at the increasing number of hybrid installations occurring now across the superyacht sector, then you can tackle one of the most wasteful issues. Generators installed to service considerable house loads are often incorrectly load balanced; a suggestion from the panel was that generation plant onboard some of the global superyacht fleet may be running at as low as 20%-30% efficiency.
Most modern hybrid systems are now stepping well beyond their propulsion brief to use energy storage either to supplement or even completely replace one or more of the generators aboard. The aim being to get much more energy efficiency from every litre of diesel burned.
A new kind of cool
Looking at why so much generation is needed in the first place, the obvious big target is air conditioning. Again, a refit can deliver significant savings in power consumption, as much as nearly two-thirds of typical consumption on a legacy superyacht if all potential areas of improvement are tackled.The first savings may well simply come from just changing the settings and use profile of the HVAC system. Beyond that, an investigation of the chiller, how advanced it is and whether replacement would yield gains, or considering transitioning from chilled water to direct expansion.
More substantial work might include changes to the ducts and airflow in the yacht, a source of potentially large gains. A lot of yachts dating back to around 2010 were designed to deliver high volumes of fresh air, which can lead to large energy losses. The hold-back on progress here being the difficulty of making changes without expensive disruption to expensive and complex interior fit-outs.
Pushing sustainability further up the refit agenda
Despite challenges, you can create an objective return on investment report if upgrading superyachts during refit to reduce their environmental impact. It helps that there will be sound data of superyacht’s operational use to date and independent energy audits such as the Water Revolution Foundation’s YETI (Yacht Environmental Transparency Index) are gaining traction. From that can flow a list of suggested changes and improvements with realistic estimates of what they will mean to owners and their families, both in terms of operational savings and improvements to their impact upon the planet.So why are refits that place sustainability as a high priority still relatively rare in 2026?
One answer to that question may be found in the business background of superyacht owners who may look positively on the original capital expenditure of yacht as an investment in their leisure time or status, but frown on increases in operational costs due to an expensive mid-life refit. There is also some resistance to what might be perceived as upselling or even greenwashing.There may also be understandable reluctance too from yards in suggesting sustainable alternatives in the face of a precise refit brief driven by owners or their representatives. Classically trained salespeople know to address pain points presented by a customer and close the deal accordingly; it takes a braver person to suggest something that could be more expensive and less proven.
The panel universally agreed that sustainability may often be successfully driven through as an understood secondary benefit to primary priorities. Looking again at HVAC systems, another way to reduce power consumption is to improve shading or even reglaze with high technology solar controlled glass. Both initiatives can be hard to introduce with sustainability as the primary benefit. However, the owner may well be much more easily persuaded if a new set of awnings means greater comfort out on deck, or if the glazing is degraded or too transparent for his liking.
It’s a similar story with transom extensions. The growing trend for legacy superyachts to be lengthened aft is that this work provides scope for an improved swim platform or beach club, capacity for more toys or even some expanded space below deck. The sustainability gain however comes from improved hull efficiency, with a further bonus for the owner to consider that seakeeping may also be improved.
It’s important that these gains in environmental footprint are communicated well to the owner, irrespective of whether they were the original motive for authorising the work within a refit. Another important consideration is to have the refit planned as far in advance as possible, to maximise the possibility of incorporating more sustainable options within proposed solutions.
A further suggestion is to try and excite owners about the long-term potential they have in their yacht, or the one they're looking at buying. The proposal might even be a multi-year, multi-refit plan, with a lot of planning sat behind it. What you would then be selling is a controlled transition towards a future-proof yacht with the ultimate goals of each step mapped out.
Importance of pioneers
There is recognition that, just as with new builds, the superyacht industry is reliant on pioneers of sustainable practice and technology among its owner cohort. We’re on the very steep part of the innovator curve where it takes a certain level of courage and determination from owners and representatives to agree to step outside of a proven norm. Given the pace of change of technology and the small volume of superyachts in significant refits and builds each year, chances are the decision to implement a new sustainable solution may be committing to just its first, second or third iteration.
Similarly, the panel recognised that shipyards also need to play their part as pioneers, to invest, develop and prove with partners the technologies of tomorrow. Putting a yard’s money where its mouth will certainly assist owners to commit to concepts that may make a substantial difference in the future.Immaculate is not enough
Irrespective of short-term return on investment, the panel also recognised that there may be a more important imperative to drive all refits towards driving environmental reduction in the future.Basic refits only are likely to impact value over coming years. If you are not making your yacht more sustainable over time it might be immaculate but is it becoming obsolete? The advent of emission regulations and other environmental regulations and protected areas could ultimately result in use of a beautifully maintained but older specification superyacht being constrained. There's an enormous amount of uncertainty around forthcoming regulations – by future proofing your yacht and upgrading it, you are hedging against uncertainty.
A vessel upgraded in refits to be more sustainable is not just an old yacht on the market. It's something which is still relevant, still looks cool, but has the appeal of more compliant and efficient operation. One which the children of owners’ will also be more comfortable with as they consider their own environmental impacts.
The panel
The Superyacht Forum’s 2025 Justifying Sustainable Refits – ROI & The Value Beyond panel comprised:
- Hanneke Grijpma, Founder and CEO, xullux
- Simon Brealey, Head of Consulting Services, Lateral
- Rob Papworth, CEO, MB92 La Ciotat
- Alberto Perrone Da Zara, Director Sales Yacht Refit, Lürssen
- Tobias Kohl, Vice President Application Engineering Marine, Rolls-Royce Solutions GmbH
The audience was also interactively involved in the discussion through polling and a Q&A.
