At first, he considered installing solar panels on deck. But during the dark winter months, they would barely generate any power. Switching to electric propulsion sounded promising too, until he learned that the electricity grid in the Netherlands is already heavily overloaded. And adopting a new, cleaner fuel? For a centuries-old steamboat, that is technically almost impossible.
That is why he visited Sander Huisman, adjunct professor and expert in fluid physics – the study of currents – for this question in the Sinteresting series. Sander researches how water moves around a ship, how resistance is created, and above all, how you can reduce that resistance to make ships sail more efficiently.
The hidden forces beneath the surface
When Sander hears about the problem, he immediately sees where the challenge lies. “A ship may look as though it simply glides through the water,” he explains, “but beneath the surface things are far more complex. The hull is constantly slowed down by different kinds of resistance: friction, waves, pressure differences. Together, these determine how much energy a ship needs to move forward.”
Sander and his research group focus particularly on friction along the hull, because it accounts for a large part of a ship’s fuel consumption. The rougher the hull – due to weld seams, algae, or shell growth, the more energy is lost to the surrounding water.
Bubbles under the hull
In his research, Sander discovered something rather surprising. “When you pump large air bubbles underneath the hull, something special happens,” he says. “The bubbles deform under water pressure and form a thin layer of air between the water and the ship. That layer works like a lubricant, meaning the hull makes less direct contact with the water.”
The result: significantly reduced resistance. And although the image sounds unusual, a steamboat gliding over a carpet of bubbles, the results are convincing. In clean water, resistance can drop by up to 40 percent with only 4 percent air injection.
How much more efficient can the steamboat become?
The precise improvement varies per ship. A hull covered in marine growth will benefit less than a clean one, and salt levels and particles in the water also play a role. But one thing is certain: air bubbles always reduce resistance. And for a steamboat that has been sailing for generations, every percent gained is welcome.
Sinterklaas can already picture it: a boat that not only brings joy to children, but also helps protect the planet.
Technology that is closer than you think
This bubble technology comes straight from modern ship hydrodynamics. Large commercial ships already experiment with it to save fuel and cut emissions. That makes the step to Sinterklaas’ steamboat surprisingly logical: what works in global shipping might work just as well in his festive logistics.
Sander’s research shows that fluid dynamics is far from abstract. It is knowledge that helps the world move forward, including Sinterklaas.
Watch the video to see how Sander and Sinterklaas explore whether bubble technology can make the steamboat cleaner and more efficient.
