Innovations in the gas carrier segment – technologies and pioneering projects
Innovations in the gas carrier segment – technologies and pioneering projects
Many research and development activities throughout the shipping industry demonstrate that the IMO goal to achieve net-zero greenhouse gas emissions by 2050 is being taken very seriously. In the gas carrier segment DNV has been able to issue a considerable number of approvals in principle for innovative technical solutions to some key challenges in connection with the production and handling of hydrogen, ammonia and LNG, as well as carbon capture and storage, fuel cells, wind-assisted propulsion and digitalization of inspections. Furthermore, through various joint industry projects and memoranda of understanding, DNV promotes technologies with potential to propel the shipping industry in general, and the gas carrier segment in particular, towards a zero-carbon future.
Managing the liquefied hydrogen transport challenge
Using offshore wind or photovoltaic energy to power hydrogen-producing electrolysers is considered one of the key technologies for a successful energy transition. However, as the smallest of all molecules, H2 escapes easily and is difficult to handle, store and transport. Liquefying hydrogen requires chilling to −253°C. DNV has awarded two approvals in principle to France-based Gaztransport & Technigaz (GTT) for the design of a membrane-type containment system for liquefied hydrogen (LH₂) as well as the preliminary concept design of an LH₂ carrier. Both projects are part of an agreement with Shell and constitute important steps towards the development of an efficient hydrogen supply chain.
Floating green ammonia FPSO unit
Ammonia has been recognized as a key energy carrier for the energy transition. Apart from its traditional uses in fertilizer and chemical production, it can be used as a carbon-free fuel and a hydrogen transport and storage medium. The Norway-based company H2 Carrier has developed a design for a floating green ammonia production, storage and offloading unit (FPSO) which has received approval in principle from DNV. Based on the conversion of an existing Very Large Gas Carrier, the FPSO would use renewable electricity for electrolysis of seawater and convert the resulting hydrogen into ammonia using nitrogen it likewise produces on board. The innovative P2XFloater provides a low-cost, fast-track and flexible solution for the production of green ammonia at a competitive price.
Fixed and floating ammonia bunkering terminals
Anticipating the passage of IMO regulations for the use of ammonia as a ship fuel – and potentially a zero-carbon fuel – the industry is taking steps to establish ammonia bunkering infrastructure. DNV has granted approval in principle to the Norwegian company Azane Fuel Solutions for its ammonia bunkering and loading terminal design. Azane, a joint venture between ECONNECT Energy, an expert in safe gas handling, storage and transfer systems, and the ship project developer Amon Maritime, want to offer its proprietary ammonia bunkering terminals as a safe, turnkey solution for ports in northern Europe and around the world, filling a gap in the ammonia value chain.
Green ammonia tanker powered by ammonia
Grieg Edge, LMG Marin and Wärtsilä have jointly designed a concept for an ammonia carrier which has recently obtained DNV approval in principle. The ship is not only designed to transport green ammonia but also to use it as fuel. Called MS Green Ammonia, the tanker concept is part of a larger project of a group of Norwegian companies who plan to use wind power to produce green ammonia and have the MS Green Ammonia transport it to land storage facilities along the Norwegian coast or serve as a bunker ship for future ammonia-fuelled vessels. Some 120 metres in length and powered by a Wärtsilä ammonia engine, the carrier will be able to transport 7,500 cubic metres of cargo.
Upscaling on-board fuel cell technology
A consortium consisting of Shell, the three Korean companies Doosan Fuel Cell, its subsidiary Hyaxiom, and Korea Shipbuilding & Offshore Engineering (KSOE), as well as DNV has been formed to develop fuel cells as auxiliary on-board power units. Fuel cells have long been studied as a means to reduce the fuel consumption of ships. The consortium plans to first install a 600 kW demonstration solid oxide fuel cell (SOFC) system on a 174,000 cubic metre liquefied natural gas carrier to be built by KSOE. As a longer-term plan, the consortium aims to develop ships powered by solid oxide fuel cells. DNV will be in charge of approving drawings, inspecting the facilities, and certifying the demonstration ship.
Liquefied carbon dioxide carrier for the age of Carbon capture, utilisation and storage (CCUS)
Capturing carbon emissions from combustion processes, whether based on fossil or green fuels, can help reduce atmospheric carbon. Captured carbon dioxide (CO2) can either be used to synthesize other fuels, such as methanol, or pumped into underground geological formations for permanent storage. Being able to do so in an economically feasible manner requires a CO2 value chain including liquefied CO2 (or LCO2) carriers. DNV has awarded an approval in principle to Mitsui O.S.K. Lines, Ltd. (MOL) and Mitsubishi Shipbuilding Co., Ltd. (MHIMSB) for their joint design of a 50,000-cubic-metre-class LCO2 carrier, a demonstration project. The industry expects the demand for this ship type to grow considerably.
Comprehensive LCO2 carrier design using bilobe tanks
A variety of approaches to transporting LCO2 are being studied and developed. DNV has awarded an approval in principle to Samsung Heavy Industries (SHI) for an innovative LCO2 carrier design incorporating large, custom-developed IMO type-C bilobe cargo tanks, a reliable cargo handling system, and a high-efficiency reliquefaction system. Featuring optimized cargo space and operational performance, the carrier design is intended to support future large-scale LCO2 transport demand.
Ambient-temperature, vertical-cylinder LCO2 tank system for larger ships
Knutsen NYK Carbon Carriers (KNCC), a new joint venture company established by the Knutsen Group and the NYK Group, has developed a “PCO2” tank system for transporting LCO2. Designed for larger ships and an efficient CO2 value chain, the PCO2 concept aims to tackle the scaling challenge by transporting liquefied CO2 at ambient temperatures in the range of 0–10°C. This is accomplished by storing the liquefied gas in bundles of vertically stacked small-diameter pressure cylinders rather than large cylindrical tanks. By transporting LCO2 under these conditions, the concept aims to significantly scale transport volumes compared to existing solutions while maintaining a relatively uniform product across the transport chain in terms of pressure, temperature and state.
Optimized, lower-cost liquefied natural gas (LNG) carrier design
Amid the recent energy crisis and political uncertainty, the need for LNG transport has obtained new urgency, especially for Europe. The French LNG containment specialist GTT has received approval in principle from DNV for its three-tank, 174,000 cubic metre LNG carrier design. The concept aims to increase the profitability and overall performance of the vessel by using three cargo tanks instead of four, reducing construction costs. The “Mark III Flex” technology improves the ratio between the volume of LNG transported and the surface area of the cryogenic liner to reduce the daily boil-off rate.
Combined-cycle power plant minimizes methane slip from LNG carriers
A consortium comprising Siemens Energy, Moss Maritime, DNV and Fearnleys has developed an LNG vessel design that will be powered by a hybrid combined-cycle power and propulsion plant featuring an SGT 400 gas turbine combined with a heat recovery steam generator, steam turbine and BlueVault energy storage solution for the electrical propulsion and distribution system. The hybrid power plant burns fuel very efficiently, minimizing methane slip, a key concern for LNG-fuelled ships. The design also reduces the number of components and thereby the newbuilding costs. DNV estimates the vessel to reduce CO2-equivalent emissions by 11–18% and unit freight costs by 9–17% compared to current LNG carriers.
Rotor sail and other wind-assisted propulsion solutions
Daewoo Shipbuilding & Marine Engineering (DSME) and DNV have signed a memorandum of understanding (MOU) to jointly develop ship wind-assisted propulsion systems, including a rotor sail solution. DNV will provide type approval design certification (TADC) and technical support for DSME’s future rotor sail system. The two partners will conduct a joint study of a wind-assisted propulsion system (WAPS) on deep-sea vessels such as LNG carriers and VLCCs. DNV provides a range of WAPS-related services, such as classification, certification and advisory, and will release enhanced standards ensuring general safety improvements for ships with WAPS.
Streamlining surveys through digital twin technology
DNV has awarded an approval in principle to HHI Group for their innovative Hyundai Intelligent Digital Twin Ship (HiDTS) system, confirming that the system meets the requirements of the DNV Data-Driven Verification class notation for the power management system (PMS) with the digital twin qualifier. This will enable extensive and convenient inspection of the PMS system using a digital twin without a surveyor having to attend physically while allowing reliable PMS test run data to be collected and played back for surveying. The documented data remains accessible indefinitely. A new MOU between Korea Shipbuilding & Offshore Engineering (KSOE), Hyundai Heavy Industries (HHI) and DNV will further investigate the practicability of digital twin as well as autonomous technologies.