The climate economics of the world’s 6,000 superyachts: ‘It’s not an entirely rational decision’

The greenhouse effect pollution caused by luxury vessels, which benefit so few superyachts, has prompted sociologist Gregory Salle to describe it as a form of “ecocide” and “apparent isolation” in his new book, Superyachts: Luxury Peace and ecocide.

There are nearly 6,000 superyachts — that is, vessels more than 30 meters (100 feet) in length — at sea, according to a report earlier this year by media and market intelligence company SuperYacht Times. The total has quadrupled in the past three decades.

“It is difficult to think of a more convincing sign of wealth than that if you own a luxury yacht,” said Salle, a professor at the University of Lille in France.

The concentration of wealth has not only led to the superyacht explosion. This has also led to a split in per capita emissions, with the wealthiest people living the highest carbon lifestyles.

The richest 10% of the world's population already account for half of the world's carbon dioxide emissions, according to Oxfam research. The nonprofit found that it would take 1,500 years for someone in the bottom 99% to emit as much carbon as one of the world's biggest billionaires. The super-rich's emissions come from a variety of sources, including large homes and frequent plane travel. But luxury yachts are the single largest source of greenhouse gas emissions, according to a 2021 study.

The annual carbon dioxide emissions of the top 300 superyachts are approximately 285,000 tons, according to Sal's book, an amount greater than the entire country of Tonga.

Superyachts are also more than just climate polluters. Sewage, noise, light pollution, suspended particles in exhaust, and even where ships are anchored can have a negative impact on the local environment. These huge impacts add up to why SAL calls shipbuilding a form of ecocide.

This term – coined in the 1970s – refers to the deliberate destruction of nature and is often used to describe the actions of the wealthy due to their huge carbon footprint. In 2021, lawyers proposed codifying ecocide into international criminal law, placing it on an equal footing with genocide. EU lawmakers voted to criminalize environmental damage “similar to ecocide” earlier this year. It remains to be seen whether the new law will be used to prosecute the use of luxury yachts.

Some owners are aware of the risks their ships pose to the environment. Jeff Bezos' $500 million superyacht Koru set sail in April 2023 with sails to help power his voyage. However, they still have diesel engines. Oxfam estimates that the 127-meter (416-foot) ship has emitted 7,000 tons of carbon dioxide over the past year, an amount equivalent to the annual emissions of 445 average Americans.

It is also certain that this estimate is at the lower end, as calculations indicate that the yacht is in standby mode and not in transit. The figure also does not include Koro's companion yacht, Abeona, a 75-metre motor yacht that functions like a garage with a helipad and jet skis.

The sails on Bezos' ship are an exception: the vast majority of superyachts are motor-powered only. Only eight new yachts were completed in 2023, compared to 195 new motor yachts.

Understanding the true carbon emissions of superyachts is extremely difficult due to the lack of data collected and the secretive nature of yachting, according to Malcolm Jacutin, founder of superyacht consultancy Three Sixty Marine. Using IMO data, Jacutin estimates that yachting emissions will reach 10 million tonnes by 2030 if the industry follows a “business as usual” approach.

To help owners understand the impact of their boats, he developed two carbon emissions calculators. However, they have limitations, because they rely on voluntarily reported data and estimated tons of diesel fuel.

Yachts spend between 10% and 20% of the year sailing and rely on engine power. Boats reach their top speed only 0.1% of the time during the year, according to Robert Van Tol, executive director of the Water Revolution Foundation. The rest of the year, the ship is a floating hotel, relying on generators needed for a longer period of time, and producing more carbon dioxide, Jacotin calculates.

However, emissions data is done on a boat-by-boat basis, and one yacht may travel more than another in a year, making travel emissions higher, according to Oxfam researchers. Yachts are exempt from IMO emissions rules, so it is difficult to discern any boat's true emissions. This reflects how luxury yachts are somewhat ostentatious and unknown.

“Superyachts are built to attract attention,” Sal said. “But they're also really secret vehicles, meaning you can't get inside if you're not invited.”

The new designs focus less on getting the engines to top speeds and more on saving power in hotel mode. But sustainability may not be at the forefront of purchasing decisions.

“Buying a yacht is not a completely rational decision,” said Ralph Daziert, head of media and market intelligence at SuperYacht Times. “It's very emotional because it costs you an absolute fortune.”

In 2023, the combined value of yachts sold reached €4.6 billion ($4.9 billion), according to Desert. He said the movement toward sustainability will be largely driven by shipyards and engineers adding features to new buildings, including the use of recycled materials. New types of fuels can also reduce emissions.

This year, Italian shipbuilder Sanlorenzo will test the first 50-meter steel yacht powered by hydrogen fuel cells, and another 114-meter yacht from German shipbuilder Lürssen with the same technology is in production in 2025 for Mark, a former watch developer for Apple Inc. Journalist day.

But the larger the building, the longer the waiting time. This means that some of these features will take years to appear on the high seas, according to Jacutin.

In an effort to improve the image of superyachts, some owners are making their yachts available for research and exploration. This includes a new 195-meter yacht owned by Norwegian billionaire Kjell Inge Röcke, which is scheduled to launch in 2026 with more than 50 scientists to study the ocean. (It is also available for custom cruises.)

While public scrutiny is increasing, the superyacht industry is a client-driven industry. For most buyers, luxury still trumps climate concerns. Salle pointed out that superyachts, like many high-end items, are not just products. They represent a “way of life,” one that is now closely associated with carbon-intensive activities.

“Ecocide is something that causes profound damage, damage that lasts over time,” Sall said. “You can apply that to what (superyachts) do, not just on an individual level… but on a global level.”