Merchant ships are harnessing the wind to reduce emissions

NEW YORK - One ship was pulled across the sea with the help of an enormous sail that looked as if it belonged to a kite-surfing giant. Another navigated the oceans between China and Brazil this summer with steel and composite-glass sails as high as three telephone poles.

Both harness a natural propellant that ocean-going vessels have depended on for centuries: the wind. And they’re part of a growing effort to move the shipping industry away from fossil fuels.

“We want to decarbonise – why not use what’s available?” said Mr Jan Dieleman, president of Cargill Ocean Transportation, which charters about 700 ships. “Wind is free fuel.”

The worldwide shipping industry is responsible for about 3 per cent of the greenhouse gases that are dangerously heating the planet. That translates into about 1 billion metric tonnes of carbon dioxide and other gases annually, a figure that is rising as global trade increases.

Some 11 billion tonnes of cargo are shipped by sea each year, accounting for as much as 90 per cent of the world’s traded goods. Nearly all of it is enabled by burning heavy fuel oil, but that is beginning to change.

Cargill chartered the Pyxis Ocean, a vessel that began its first wind-assisted voyage in August. It sailed from China to Brazil with two wings that turned to capture the wind and folded down when not in use. While each weighs 125 tonnes, Mr Dieleman said it is a small proportion of the vessel’s carrying potential of 82,000 tonnes. Each sail can cut fuel usage by 1.5 tonnes per day, or 4.65 fewer tonnes of carbon dioxide emissions, and decrease fuel usage by 30 per cent. The ship docked in Brazil last week.

The French company Airseas developed a different design, the outsize kite. It is housed in a storage tank on a ship’s bow and deployed by cable and crane to slice nearly 1,000 feet into the sky, where winds blow strong. A prototype has been at sea for a year and a half, said Mr Vincent Bernatets, the CEO and co-founder of Airseas. The design could slash fuel consumption by up to 40 per cent on some routes, he said, adding that a major Japanese ship company has ordered five sails.

Wind-powered ships still need a backup fuel to navigate harbours or to function when the air is still. But the idea is to significantly reduce the reliance on fossil fuels.

“Every tonne of carbon you save is actually a third of a tonne of fuel that you save,” Mr Dieleman said. “We need to get the emissions profile down today.”

Of a worldwide fleet of about 60,000 cargo ships, roughly 30 are wind-assisted, said Mr Gavin Allwright, the secretary-general of the International Windship Association, a trade group. But as many as 10,700 merchant ships are projected to use wind propulsion by 2030, he said.

“We think this will go much quicker,” Mr Allwright said. “Is the industry going to adopt this? The answer is yes, increasingly so.”

Nearly all nations have agreed to stop adding emissions from shipping to the atmosphere by 2050, a target that depends greatly on zero-carbon fuels, such as ammonia that is produced with wind or solar energy. But those fuels would be expensive, and toxic leaks are a concern.

“It’s a bit of a battle of visions,” said Mr John Maggs, the shipping policy director at Seas at Risk, a coalition of environmental groups that is based in Brussels. “Shipping is a very conservative industry, and of course the companies selling fossil fuels will be selling those alternative fuels.”

Research has found that shipping emissions could be cut by up to 47 per cent by 2030 through a combination of wind propulsion, new fuels and reduced speeds. Slowing down could also cut underwater noise and risks to whales. An estimated 20,000 whales are killed each year by ships, according to Friend of the Sea, which certifies fisheries and aquaculture for sustainability.

Dozens of other wind-ships are in development, many in European countries like Britain, France, Norway and the Netherlands. Almost all are highly automated and equipped with sensors, with designs that include sails, rotors and parts that resemble vertical airplane wings.

Their builders would not discuss the costs, but estimates for adding wind propulsion range from several hundred thousand dollars to more than US$1 million (S$1.4 million). The payback period could be three to five years for retrofits and longer for new builds, Mr Allwright said.

The Swedish company Wallenius Marine is developing wind-powered ships with the aim of lowering vessels’ carbon emissions by as much as 90 per cent. The company has sponsored Abba Voyage, a virtual concert performance featuring the Swedish pop band that has been running in London since last year. Mr Richard Jeppsson, the senior vice-president for wind-powered projects with Wallenius Lines, said the company advised on the show’s sustainability, ensuring that water was recirculated and that renewable building materials were used.

Wallenius has also secured the rights to name its wind-powered vessels after Abba songs. Although the band’s song, Eagle, accompanies a promotional video, Mr Jeppsson said an Abba song has yet to be chosen for one of the ships.

“Some are better than others,” Mr Jeppsson said. “Maybe not SOS.” NYTIMES