Recent months have seen rapid progress in the application of wind power to help reduce tanker emissions
The main reason rotor sails and other low-wind speed sail technology for commercial vessels has not been previously exploited is the absence of a viable market. That changed with the imposition of IMO’s greenhouse gas (GHG) decarbonisation targets. The first company in the modern era to apply wind power to tankers was Finnish company Norsepower, which uses the Magnus affect to derive extra energy (above that need to power the system) from rotor sails.
Norsepower’s solution pre-dates IMO GHG targets and with operator Maersk Tankers, it was already experimenting with sail power. In 2018, Maersk Tankers’ Maersk Pelican, a 2008-built LR2 product tanker, was fitted with two 30-m tall rotating sails.
The rotor sails installed onboard Maersk Pelican achieved an aggregated total fuel saving between 1 September 2018 to 1 September 2019 of 8.2%. This is equivalent to approximately 1,400 tonnes of CO2. The savings were confirmed by comparing detailed performance information to a baseline, established with full scale measurements and computational analysis done for the vessel prior the rotor sail installation.
Along with Maersk Tankers and Norsepower, Energy Technologies Institute (ETI) and Shell Shipping & Maritime are the project partners behind the project, which moved into the next stage with the announcement of a service agreement with Wärtsilä.
Wärtsilä has also signed a memorandum of understanding, tied to a licence and co-operation agreement, with UK-based Anemoi Marine Technologies for the future sales and servicing of its rotor sails within its propulsion business. As part of the agreement, Anemoi’s rotor sails will soon be offered as part of Wärtsilä’s marine portfolio. Anemoi Marine Technologies rotor sails are proposed for a 114,000-dwt Aframax tanker, a 50,000-dwt MR tanker and VLCC designs as part of a joint development project with Lloyd’s Register (LR) and Shanghai Merchant Ship Design and Research Institute (SDARI). Along with the installation of rotor sails, the vessels could also incorporate new hull forms, new energy management systems, a new powering arrangement and modified operational requirements. LR will review the designs in accordance with the latest regulatory requirements and issue an Approval in Principle (AiP).
“Large, solid wing sails up to 45 m in height will reduce CO2 emissions by as much as 30%”
LR is also involved in another rotor sail project. It has presented Hyundai Heavy Industries Co (HHI) with AiP for a VLCC ‘eco-tanker’ design, capable of using a combination of volatile organic compounds (VOC) mixed with LNG as fuel and Norsepower’s rotor sail solution for wind-assisted propulsion. This was the result of a joint development project between HHI, LR and Norsepower. The AiP has been verified for interface and control logic stability with other systems, resulting in reduced emissions and improved efficiency.
LR was involved assessing of the impact of installing Norsepower’s rotor sail solution, including structural reinforcement and visibility calculations. This was reviewed using computational fluid dynamics during the project. It was confirmed that the solution has the potential to provide 5-7% fuel savings, dependent on operating routes.
Another class society involved in supplementing wind-power for tankers is DNV GL, which has also awarded an AiP to Korea Shipbuilding and Offshore Engineering (KSOE). The KSOE wind-powered auxiliary propulsion system for ships is the result of a joint research project from KSOE, the shipbuilding holding company of Hyundai Heavy Industries Group, and SK Shipping, to develop wind-powered eco-friendly propulsion solutions.
The wing sail design is 20 m wide, 50 m high and installed vertically on both sides of the deck. It rotates its wings according to the direction and intensity of the wind to provide auxiliary propulsion to the ship. The wing can be lowered to 10 m in height, making it flexible in case of bad weather or when passing under a bridge.
DNV GL undertook the AiP by reviewing initial drawings related to design loads, system responses, redundancies and components submitted by KSOE, while SK Shipping provided its expertise and insight on the technology from an owner’s point of view. “As a result of the joint research with two leaders of South Korea’s maritime cluster, it was a meaningful project to which we contributed our expertise,” said DNV GL regional manager Korea and Japan Vidar Dolonen. “Wind propulsion for ships is an effective solution which helps to meet IMO’s regulations for greener shipping,” he added.
The AiP is also a big step towards awarding DNV GL’s new additional class notation, WAPS (Wind Assisted Propulsion System). In addition, DNV GL has recently developed a standard for the certification of wind-assisted propulsion systems in response to enquiries for an independent assessment of those systems.
Stena Bulk has a history of tanker design innovations – V-Max, P-Max, IMOIIMAX – and has now designed the IMOFlexMAX. This latest chemical and product tanker design aims to reduce GHG emissions by at least 25% on current designs by using Flettner rotors and solar panels to harvest energy from wind and sunlight. The IMOFlexMAX design will be powered by efficient dual-fuel engines that can run on LNG as well as conventional low-sulphur fuels using the latest engine technology.
“The wings rotate according to the direction and intensity of the wind to provide auxiliary propulsion to the vessel”
Yacht racing has always been at the sharp end of wind-powered ‘transportation’, with the America’s Cup race being the pinnacle of this sport. The current British contender is led by Sir Ben Ainslie and the emergence of his BAR Technologies could take the application of sail power to another level. The creation of BAR Technologies makes for a compelling story: a combination of a medal-winning sailor who has applied his knowledge of sailing dynamics alongside the computational dynamics modelling from the world of Formula 1, used to leverage solutions for the shipping industry.
Bringing the funds and the ships to the project is commodity trading giant, shipowner and operator, Cargill of Switzerland. The project will see BAR Technologies’ WindWings – large, solid wing sails that measure up to 45 m in height – fitted to the deck of Cargill’s product tanker and dry bulk carriers to harness the power of the wind and reduce CO2 emissions by as much as 30%. The number of wing sails can be tailored to the size of the vessel and the route it will take.
BAR Technologies – a spin-off endeavour from Ben Ainslie Racing (BAR), the team the Olympic and World Champion sailor created – was formed in 2016 to make the design knowledge, technical skills and intellectual property developed for America’s Cup yacht racing available for commercial pursuits. BAR Technologies has an impressive team sheet of senior managers from the world of hi-tech sport. The chairman of BAR Technologies is Martin Whitmarsh, the former principal and chief executive officer of Formula One racing team McLaren. McLaren’s former chief commercial officer John Cooper has taken on the chief executive officer role at BAR Technologies and the design team is led by former America’s Cup designer and engineer, Simon Schofield.
The project, currently in the design phase, is predicated on IMO’s GHG challenge to the industry to reduce average CO2 emissions by at least 50%, but working towards 70% by 2050, compared with 2008 levels. The first sails are to be fitted to product tankers in the Cargill fleet by 2022.