[imagesource:youtubescreenshot/universityofmiami]

A new wind-driven system by startup CoFlow Jet promises to reduce shipping fuel costs by up to 90% using stationary cylinders with no moving parts.

Looking like old-school chimneys, these cylindrical erections take a page from the history books as the shipping industry looks at ways to readopt sails and harness the wind.

The new outlook is due to rising fuel costs and increasing government mandates requiring shipping companies to go carbon neutral by 2050, which has resulted in a strong push to increase the efficiency of cargo ships while reducing their emissions.

For centuries, sails have propelled ships all across the world, and they were still employed for commercial shipping until well after WWII. However, several issues with sails have driven them out of the freight market for all but the most local niches.

Firstly, sails require huge crews to manage. The famous clipper Cutty Sark needed a crew of about 30 just to handle the sails and the complex sheets and lines that controlled them. Compared to modern 196,000-tonne container ships that only need 13 officers and sailors – most of them pushing buttons instead of hauling lines – it’s easy to understand how ‘hoisting the sails’ can be an issue.

The second biggest obstacle is the wind, or rather, the unpredictability thereof. If it blows in the right direction, great. If in the wrong direction, or not at all, it’s not so great.

For these reasons, steam and later diesel power became the go-to options for cargo ships, with only hardened explorers and pleasure yachts still preferring sails.

Sails are undergoing a renaissance, but unlike the old canvas and ropes methods, modern shipping companies are looking to technologies like kites and wind vanes, with some even using the hull of the ship itself as a sail.

CoFlow is however focussing on a variant of the old Flettner rotors developed in the 1920s.

Flettner rotors are smooth cylinders with disc end plates which is spun along their long axis and, as air passes at right angles across it, the Magnus effect causes an aerodynamic force to be generated in the direction perpendicular to both the long axis and the direction of airflow.

Outside of Wikipedia, this means drawing in a small amount of air from the intake, pressurizing it using an impeller, and then squirting it through the outlet, which generates a pressure imbalance and a considerable amount of thrust.

GeCheng Zha, a professor of aerospace engineering and director of the Aerodynamics and Computational Fluid Dynamics Lab at the University of Miami College of Engineering says this method allows for a very effective wind propulsion system that can provide 100% of the needed thrust to move the ship.

What makes CoFlow’s system unique is that it can be retrofitted to existing vessels and the cylinders can be retracted to get in and out of harbours.

“What’s old is new again.”

“With the technological advancements of today, wind-assisted propulsion is an efficient alternative to diesel engines. And the major advantage is that it’s environmentally friendly – an effective way to decarbonize the shipping industry that’s responsible for about 3% of global greenhouse gas emissions. The shipping industry has had a tendency to resist change because diesel engines are so powerful but now, with pressure mounting, either willingly or unwillingly, it will have to change.”

The cargo industry is continuously looking to new technology to improve its efficiency while coming to grips with the realities of global warming. However, sometimes the answer lies in the past, and with a little help from tomorrow, we can adapt and improve outdated ways.

Who knows, one day our freight forwarding and shipping partner, Berry & Donaldson, might be shipping your precious cargo using modern technology inspired by old sailing ships.

[source:newatlas]