Sailing to the Future

The 29-day voyage of the “Grain de Sail” from Saint Malo, France to New York, New York, completed on December 16, 2020, was not publicized in the New York Times, USA Today, or any other big-name tabloids. Its cargo of about 14,000 bottles of wine has yet to hit the menus of New York restaurants and the shelves of retailers, and is far from the largest cargo of wine ever recorded. (Archeological discoveries have found wrecks of ships from around the 1st century BCE that were capable of carrying 9,500 gallons of wine – approximately 48,000 bottles.) Although sailing may not be the most economical method of transporting goods, this achievement should not be understated as it signifies an earnest effort towards zero-carbon shipping.

The Grain de Sail is a traditional-sail-powered vessel delivering cargo across the Atlantic.

Applying Tried-and-True Technology Today

As vessel owners and operators scramble to invent new ways to reduce their carbon footprint, the “Grain de Sail” looked to the past for a more ecologically friendly way to transport goods. Many are following suit. Companies like New Dawn Traders and Sailcargo have risen alongside Grain de Sail to provide the global economy a clean and sustainable alternative shipping method using a traditional sail propulsion approach.

Meanwhile, others are installing more modern sail technology, like Flettner rotors, to capture the energy supplied by the wind. A newbuild large bulk carrier set to be delivered in 2021 will be the first bulk carrier with five of Norsepower Oy’s tilting rotor sails to aid in the vessel’s propulsion.

One of the more famous shipbuilding projects using wind power, Wallenius Marine’s “OceanBird” concept proposes to be a roll-on roll-off vehicle carrier with a 7,000-car capacity, and will be powered entirely by five 80-meter-tall retractable sails. Essentially, it will be the plug-in hybrid of cargo ships: using an internal combustion fuel engine to get going and green energy to cruise. However, construction of this vessel won’t start until about 2024.

OceanBird shows how modern sail technology can be used in hybrid ship designs.

Sail Savings

Norsepower claims that retrofitting Flettner rotors on existing ships can increase savings by up to 25%, as a result of reduction in fuel consumption and emissions. They also claim that annual CO2 emissions would reduce by 30 million metric tons if the rotor sail technology were applied to the global tanker fleet, however ironic this may be. In 2018, Norsepower installed Flettner rotors on the crude oil tanker Maersk “Pelican”. The fuel consumption was independently verified, and the rotor sails were found to reduce fuel consumption by 8.2%, preliminarily indicating that this technology of old can be applied on modern cargo ships successfully.

Maersk Pelican with Flettner rotors exhibits energy savings with modern sails.

As of January 20, 2021, Norsepower has successfully retrofitted the Ro/Ro “SC Connector” with tiltable Flettner rotors. These are reportedly the first of their kind and mark another step forward in advancing sail power in the global merchant fleet.

One setback to this technology is that long and sometimes unpredictable voyage times associated with vessels solely powered by wind – up to a month – forces the logistics to be planned even further in advance and turns many companies away from the technology. Even vessels fitted with rotors or sails as propulsion assistance expect a voyage across the Atlantic Ocean to take about two days longer than a vessel powered fully by a hydrocarbon-based fuel.

Nonetheless, the journey of the “Grain de Sail” and the expansion of the use of wind power in the global shipping market illustrates that innovation is driven by people who “just do it”. Even if using various sail technologies does not solve the problems of using fossil fuels outright, it shows that inventiveness and willpower are what instigate change.

Martin & Ottaway