Environmental concerns are influencing a greater need for renewable and sustainable energy across the world with specialist technologies being at the forefront of new designs and solutions. The environmental impact of shipping includes air pollution, water pollution, acoustic, and oil pollution. Commercial ships are responsible for more than 18 percent of some air pollutants, including greenhouse gas emissions. The International Maritime Organization (IMO) estimates that carbon dioxide emissions from shipping were equal to 2.2% of the global human-made emissions in 2012 and expects them to rise 50 to 250 percent by 2050 if no action is taken. 

There is a perception that cargo transport by ship is low in air pollutants, because for equal weight and distance it is the most efficient transport method. This is particularly true in comparison to air freight. However, because sea shipment accounts for far more annual tonnage and the distances are often large, shipping’s emissions are globally substantial. A difficulty is that the year-on-year increasing amount shipping overwhelms gains in efficiency, such as from slow-steaming and improved designs. The growth in tonne-kilometres of sea shipment has averaged 4 percent yearly since the 1990’s. There are now over 100,000 transport ships at sea, of which about 6,000 are large container ships.

In 2019, new legislation stipulated that all new ships for UK waters ordered from 2025 should be designed with ‘zero-emission capable technologies’. This commitment is set out in the Clean Maritime Plan, part of the Government’s Clean Air Strategy, which aims to cut down air pollution across all sectors to protect public health and the environment. It will also help deliver the United Kingdom’s commitment to be net zero on greenhouse gases by 2050. As maritime industries begin to tackle climate change issues, ports and shipping companies are looking for carbon-free alternatives by testing potential solutions for vessels. The requirement to make a move toward greener shipping is imminent.

Wind Propulsion Technology

To address the problem of global commercial shipping, the introduction of WPT (Wind Propulsion Technology) has been evaluated. According to some recent studies, wind-assisted ship propulsion using rigid wings, sails, kites, Magnus rotors or other novel devices on some specific vessel types such as bulk carriers and tankers, have the potential of fuel savings and emission reductions around 10%.

Windship Technology Ltd, a sail power concept being developed by a consortium of key players in the global shipping industry, have evolved the latest advancements in wind turbine blade design and high performance composite solutions to achieve a much higher emission reduction of 30% on average. Their concept design could revolutionise the way tomorrow’s vessels carry goods across the world’s oceans. 

The solution, known as the Windship Auxiliary Sail Propulsion System (WASPS), uses fixed wing sail technology, whereby three masts installed on the deck of a vessel will each have three aerodynamic solid wing sails to exploit the power of the wind. Using their expertise in ship design and composite technology, the mast rigs are highly engineered for performance, strength, lightweight and efficiencies, to ensure maximum driving force. The 48m Windship Technology rig is stowable on deck through a unique, innovative stowage solution to aid port navigation and cargo handling. Its composite structure is borne out of technology and design from the wind turbine industry, ensuring reliability and longevity of greater than 25 years. The system also allows reductions in engine power to be made in order to achieve the same speed and so maximise fuel-saving and emissions reduction.

True Zero Emission Ship Design

The Windship Technology technical team  have further developed a new diesel electric ship drive system that eliminates CO2, NOX, SOX and particulate matter to True Zero whilst also incorporating large solar arrays, carbon capture, optimised hull shapes and specialised weather routing software into the overall design package.

Professor Philip Wilson, formerly Professor of Ship Dynamics at the Ship Science Department at the University of Southampton is convinced by Windship Technology’s solution saying: “The holistic approach demonstrated in this solution whereby wind power, solar power and the reduction of harmful exhaust emissions to effectively zero, are all brought together, means that at last there is a design solution that the International Maritime Organisation can champion to achieve its requirements for ‘at least’ zero carbon shipping.”

International registrar and classification society DNV will be conducting both an outside-in and inside-out verification to fully assess Windship Technology’s whole-ship design with a view to classifying emission reductions, safety and operability.

The patented UK designed Windship rig system is consistently regarded as the most powerful fuel and emission saving wind system in the market, which will materially help the shipping industry move closer towards achieving its reduction in emissions. The IMO have recently acknowledged wind propulsion as one of the solutions for the shipping industry to meet decarbonisation targets.

In order for the shipping industry to adopt these new technologies, the accurate analysis of the potential savings and the results must be presented to all stakeholders involved. In order to achieve this, improved simulation techniques are needed to optimise design and routing. Several factors need to be accounted for, including the aerodynamics of the thrust producing devices, the vessel hydrodynamics, propulsion system and the optimal routing.