The RMS Titanic, which remains the most famous cruise ship of all time, needed 640 tons of coal to power the ship—every day. The bunkers on the ill-fated ship, which sank in the North Atlantic after colliding with an iceberg on April 14, 1912, stored almost 7,000 tons of this fossil fuel. From today’s perspective, not to mention environmentally speaking, it’s nearly inconceivable. Meanwhile, although the era of coal-burning ships has passed, the topic of emissions has become considerably more important—and is the subject of intense debate.
Which is not surprising: five thousand container ships sail the world’s oceans day after day, transporting textiles, electronics and foodstuffs among the continents. Almost 90 percent of all goods are currently transported by sea. If things continue in this vein, by 2050 the amount of freight will triple. “Bigger is better” is also a maxim for cruise lines: while 15 million holidaymakers set sail in 2007, today nearly 26 million people are taking cruises. “Due to these enormous transport volumes, ships contribute a very large share of greenhouse gases and worldwide pollutant emissions,” says Christian Schneider, an expert for emissions-free propulsion systems at the German Shipbuilding and Ocean Industries Association (Verband für Schiffbau und Meerestechnik), headquartered in Hamburg, Germany.
Even today, the majority of ships run on heavy fuel oil, the cheapest and most sulfurous fuel. The International Maritime Organization (IMO) estimates that the world’s fleet emits more than a billion tons of carbon dioxide into the atmosphere annually—much more than is produced in all of Germany over the course of a year. However, global efforts to reduce climate-threatening emissions are having an effect on maritime industries. An initial tightening of regulations was recently pushed through by the IMO: accordingly, starting in 2020 ship engines will only be able to use fuels with a sulfur content of 0.5 percent, down from the current 3.5 percent.