The world’s largest cargo ships are now adopting “super-slow steaming” at speeds of 12 knots (about 14 mph), which is significantly slower than the lowered speeds of 20 knots implemented by many major companies about two years ago to save fuel, reports The Guardian.
Travel times between the U.S. and China, or between Australia and Europe, are now comparable to the speeds of American Clippers that reached 14 to 17 knots in the 1850s, according to the newspaper.
Danish shipping company Maersk has cut fuel consumption and greenhouse gas (GHG) emissions on major routes by as much as 30 percent, by cutting the top cruising speed of its ships in half over the past two years.
A recent study shows that bulk carriers can reduce emissions by up to 40 percent by running slower.
Designed to run at high speeds, ship engines burn the cheapest “bunker” oil and are not subject to the same air quality rules as cars, reports The Guardian. In 2007, the Emma Maersk, one of the world’s largest container ships, would burn around 300 tonnes of fuel a day, emitting as much as 1,000 tonnes of CO2 a day roughly as much as the 30 lowest emitting countries in the world, according to the article.
The Royal Navy and BP also are adopting different ways to reduce fuel use and cut carbon emissions. As an example cited in the article, the Ark Royal light aircraft carrier, the new Queen Mary 2 cruise liner and 350 other large commercial ships have painted their hulls with special anti-fouling paint, which has been shown to cut CO2 emissions by around 9 percent.
Other ships use kite-like “skysails“, or systems that force compressed air out of hulls, which can cut fuel consumption by up to 20 percent.