Green technologies that could transform global shipping

Although greener than flying products by plane, shipping is a carbon-intensive industry. The sector is responsible for almost 3% of global emissions, making it a bigger emitter than Germany, Canada or Iran.

In 2018, the International Maritime Organization (IMO) set a target to slash emissions by 50% by 2050, compared to 2008. As around 90% of world trade is transported by sea, cleaning up the maritime sector could make a big difference in the green transition.

Aside from emissions, shipping causes other environmental issues. Vessels can contaminate the water, disrupt marine habitats, and even erode the shoreline.

With business and governments increasingly focused on eco-friendly practices, going green looks set to be a key trend in global shipping this year. So what technologies can help the industry cut emissions and clean up its act?

Sail ships

For thousands of years, sailing boats carried cargo around the world. Now, wind power is making a comeback.

The 21st century has seen a number of sail-powered cargo companies pop up – such as Fairtransport, Sailcargo, Timbercoast and others – as eco-minded entrepreneurs look to modernise traditional technologies and harness the natural world.

While environmentally friendly, traditional sail shipping has its drawbacks. Firstly the shipping costs are higher, as sail boats typically have a much smaller cargo capacity. At the moment much of the cargo shipped by sailboat carries an eco premium and is targeted at consumers who are willing to spend a little more for ethically and environmentally responsible products.

Secondly, sail shipping tends to take longer than engine-powered alternatives, making it only suitable for goods that aren’t at risk of spoiling during the voyage.

However, smaller ships could bypass the congestion at ports, which caused havoc for supply chains during the Covid pandemic.

New technologies are forthcoming, such as the Oceanbird concept, which uses stiff wing-like sails to propel large cargo ships. The first Oceanbird prototype vessel – a 200-metre-long car carrier – will take to the seas in 2024.

Alternatives to fossil fuels

Wind power isn’t the only alternative we have to oil-based fuels. People across the industry are working on greener ways to propel cargo ships.

Renewable energy

One option is to ditch fuels altogether and opt for renewable sources of energy, such as wind-generated electricity and solar, to power the ship. Electric battery-powered engines could also be charged on land before a voyage.

Other innovations could help maximise efficiency. Sailcargo’s flagship Ceiba will use its dual propellers as underwater turbines, thereby generating electricity when moving under sail. The company is also exploring whether the sails themselves could be made of solar-fabric.

Clean fuels

Another option is to user cleaner fuels, such as liquid hydrogen or biofuel.

A team at Cambridge University is exploring how to sustainably create syngas – a mixture of hydrogen and carbon dioxide which can be used as a fuel – through artificial photosynthesis.

Artificial ‘leaves’ floating on the water’s surface use just water, carbon dioxide and sunlight to create renewable syngas.

These devices are low-cost, autonomous, and even work in low-light conditions. They could also benefit the ecosystems in which they’re placed, for instance by reducing evaporation in irrigation canals.

Foiling technology

Another area being explored is foiling technology, in which a wing-liked structure submerged under the water lifts the craft above the surface.

Hydrofoiling has been around for over a century, but has recently boomed in popularity among watersports enthusiasts and in racing yachts.

By lifting the boat out of the water, a hydrofoil significantly reduces the drag on the vessel. This allows it to move faster and requires less energy to propel it forward.

A hydrofoil boat also producers far less wake than other crafts, meaning less disruption and degradation along the coast.

Combined with some of the above technologies, like renewable fuel or battery-powered propulsion, hydrofoiling could help make green shipping a commercially competitive venture.

ARGO by Boundary Layer Technologies is designed to be one such vessel – a hydrogen-powered hydrofoiling cargo ship that can transport goods as fast as air freight but for a lower cost and with zero emissions.

The green transition

As the climate crisis looms larger, businesses around the world will come under increased pressure to move to more environmentally friendly practices. Both the EU and the US are introducing legislation to incentivise greener practices, which could lead to faster progress and lower costs in green technology. We could be on the cusp of a transformation in global shipping.