When two CO2 carriers for Norway’s Northern Lights set sail from China’s Dalian Shipbuilding in late 2024, they will be the first of a dedicated fleet transporting the waste gas to portside storage facilities.
These tankers have a cargo capacity of 7,500 m3 and overall length of 130 m. Already 60% complete, they were moved out of dry dock in early April. They will be LNG-fuelled and have wind-harnessing technology. At these proportions the vessels are roughly similar in size to LPG carriers operating today.
As a landmark review of this emerging sector by the Oxford Institute of Energy Studies (OIES), with the Carbon Capture and Storage Association and Zero Emissions Platform, published in January 2024 explains, the Northern Lights’ vessels could be the predecessors of a 40-strong fleet of CO2 carriers. Dalian is building two more tankers for Northern Lights and other newbuilds are in the pipeline.
In a round-up of the latest events in a rapidly developing industry, the review also notes that two 22,000-m3 liquefied CO2 carriers have been ordered by UK-based Capital Marine from Hyundai Mipo in South Korea. At 160-m long, these will be multi-purpose vessels capable of transporting LPG and ammonia as well as CO2 stored at -55°C. They are due to be delivered in 2025-2026.
“One technical constraint … is the difficulty of constructing very large pressure chambers”
Hyundai Mipo also has on the drawing board designs for carriers with a progressively greater capacity, ranging from 30,000 to 40,000 m3 and ultimately to 74,000 m3.
For technical reasons the capacity of these first CO2 carriers will be much smaller than that of today’s LNG tankers. “By way of comparison, the cargo capacity of the standard LNG carriers in operation today is in a range around 150,000 cm,” explains OIES. “One technical constraint that would apply to CO2 carried at high pressure, when compared to another gas carried at close to atmospheric pressure (as is the case with the larger LNG carriers), is the difficulty of constructing very large pressure chambers.”
This could change though. “Given the size of comparable 20,000-m3 gas carriers, it seems reasonable to estimate that the size of future 20,000-tonne and 40,000-tonne CO2 carriers could be in the range of 150 to 180 m,” the OIES notes.
Port development
Simultaneously, a land-based infrastructure is emerging, most notably in Europe where several CO2 terminals are under construction or planned. But it may not be happening fast enough, according to a densely researched report commissioned by the Global Centre for Maritime Decarbonisation in collaboration with Lloyd’s Register and ARUP. Released in March 2024, the report entitled Concept study to offload captured CO2 identified “low port readiness as a major hurdle bottlenecking the adoption of onboard carbon capture and storage as a practicable decarbonisation solution.”
While the necessary technologies are available “at high levels of maturity”, the operational side involving trained personnel is lagging. Most of the ports able to offload liquified CO2 (LCO2) are designed primarily to handle food-grade CO2. As the study concludes, much remains to be done portside: “For [capture and storage systems] to be operationally feasible, the industry needs to develop a collaborative ecosystem to enable the value chain for managing captured CO2.”
“Much remains to be done portside”
However, assuming the ports get up to speed, the emerging LCO2 fleet is likely to be kept busy on long-term charters sailing between large emitters, such as cement plants, with carbon capture rates of approximatively a million tonnes a year. The OIES study assumes storage sites will be located in the same region.
There are precedents for this. Four LCO2 carriers with a capacity of between 1,000-2,000 m3 have been operating for some time, including Larvik Shipping’s 1999-built, 80-m long Helle, shipping food-grade CO2. According to its website, Larvik is working with Mitsui OSK and Nippon Gas on bigger-scale LCO2 carriers and terminals. Another Norwegian shipping group, IM Skaugen, with a fleet of small CO2 carriers, collapsed in 2018 when the family-owned company lost an important financier.
New wave of ships
A new wave of bigger vessels would of course shift more CO2. According to the OIES study, a vessel with a capacity of 20,000 tonnes of liquefied CO2 with a schedule of a one-week round trip would transport approximately 1M tonnes of CO2 a year, assuming no logistical or weather delays.
Based on a review of projects currently under development, the report estimates that by 2030 up to 39.5M tonnes of CO2 could be transported a year. By then, a fleet of 10-20 vessels would be on the water. More optimistic than the Global Centre for Maritime Decarbonisation, the OIES believes storage capacity could actually exceed shipping’s ability to fill it. “Future European storage sites compatible with ship transport could exceed 50 million tonnes per year by 2030,” it predicts.
Meanwhile, the actual cost of shipping CO2 remains uncertain. Estimates from the US Gulf Coast by the Global CCS Institute put it in the range of US$15–24 per tonne of CO2, including liquefaction.
Because the cost of shipping the gas is a factor of the volumes transported and the distance sailed, large emitters, such as industrial clusters, want storage sites located relatively close by. This may entail the construction of a dedicated liquefied CO2 loading terminal, which is a highly capital-intensive investment. And as the OIES explains, this may also involve draught restrictions and operational constraints through congested areas.
Despite the challenges, Europe and the UK is pushing on with sea-borne transport of CO2, where the network of land-based pipelines falls short. According to the OIES: “Many experts working on the implementation of [carbon capture and storage] across Europe believe that non-pipeline transport, and ship transport in particular, is essential to enable CO2 transport at sufficient scale.”
Interestingly, CO2 shipping is likely to be bigger in Europe than in the US and China, where there is a bigger network of onshore pipelines and existing storage facilities.
source: rivieramm.com (Selwyn Parker)