The present-day standard of cargo ship speeds is 20-25 knots, a pretty incredible rate when you consider that the largest of container ships can carry over 150,000 tons. However, with all the current concerns about sustainability, emissions standards, and fuel efficiency, that average speed is trending downwards.
The thing about maintaining a relatively high speed is that each knot costs a little more fuel than the last one. Water actively resists the attempts of anything trying to move through it, and the harder the ship pushes, the harder the water pushes back. Speedboats minimize this effect by lifting as much of the boat out of the water as possible, because while air also resists movement, it’s not nearly as good at it.
Thus, when a cargo ship slows down by 20 percent, its fuel use drops by 40 percent. Some shipping companies are even dropping speeds to as little as 12 knots, an average rate that hasn’t been seen since steamships first took over shipping lanes from sailing vessels. Of course, 150,000 ton ships aren’t going to start putting up sails to supplement their diesel engines anytime soon, but slow and super-slow steaming are likely here to stay.
However, while that may be good news for the shipping companies in terms of international emissions standards and fuel savings, a slower average speed isn’t exactly a welcome change to all the companies who need to ship their products across the ocean. Even if time isn’t a factor, some cargo types are sensitive to temperature changes and thus need to stay in climate-controlled cargo containers, containers that demand a certain amount of energy each day to keep the interior stable.
While slow steaming may benefit the vessel’s bottom line, it adds to the overall cost which some shippers have to pay. Not only that, but every day spent in the container is a day on which the refrigeration unit might fail, spoiling the product.
Fortunately, there are alternatives to refrigeration, alternatives which are also more energy efficient and renewable. ProtekCargo offers a line of SureTemp container liners which keep the interior temperature stable against extremes of both hot and cold. On top of that, the container liners are completely sealed, offering extra protection against excess water and other contaminants.
Shipping by sea has never been particularly speedy, but pretty soon it’s going to get a whole lot slower. Make sure your products are prepared for the extended journey now so that they won’t spoil later.
