Cruise Ship Companies Are Finding It Hard to Quit Carbon

After a 13-deck cruise liner crashed into a quay in Venice this summer, residents took to the canals and bridges chanting, “No grandi navi,” or “No big ships,” and local officials vowed to bar large vessels from the city center. Concerned about overtourism and pollution from smoke-belching liners, Barcelona—Europe’s most popular cruise destination—and the Croatian city of Dubrovnik, where much of Game of Thrones was filmed, are planning limits on the number of ships that can visit. Southampton, Britain’s top passenger port, wants liners to run on shoreline electricity so they can turn off their engines while docked. “Communities find it difficult to see the benefits of these big cruise ships,” says Christopher Hammond, leader of the Southampton City Council. “It’s a very visible thing: a big funnel chucking out black soot and smoke. People think, I’m breathing all that in.”

With their brochures and websites brimming with photos of pristine blue waters and unsullied shorelines, cruise companies are profoundly aware of the importance of a spotless image. The biggest players—Carnival, Royal Caribbean International, and Norwegian Cruise Line—say they’ve made sustainability improvements such as banning some single-use plastics and increasing use of locally sourced foods, but cutting emissions is more complicated. Most ships burn a thick, sulfurous mix of the goo that’s left over after gasoline and other higher-value fuels are refined. Although some smaller boats can run on electricity, batteries can’t yet fully power a cruise liner that might spend several days at sea.