DNV has released a white paper providing insights into the critical elements in the design, construction, and operation of CO2 carrier fleet.
Carbon capture and storage (CCS) markets are developing quickly and this needs to be mirrored by growth in the CO2 carrier fleet, which can provide flexible transport of CO2 over longer distances and facilitate its transportation to final storage.
DNV’s recent Energy Transition Outlook (ETO) estimated that 210 million tonnes per annum of CO2 will be captured by 2030 and 1.3 gigatonnes per annum by 2050, equating to about 6% of global emissions.
Mathias Sørhaug, DNV Business Development Director CO2 Shipping, said: “As global CCS markets scale, the development of supporting infrastructure must keep pace. This includes a fleet of CO2 carriers, which can provide flexible, long-range transport of captured carbon across seas, as well as other maritime infrastructure elements, such as floating collection and distribution hubs and offshore storage and injection units.
“CO2 shipping presents a major opportunity for the maritime industry, but success depends on the construction of infrastructure which is safe, functional, and cost-efficient, enabling seamless downstream transportation from capture to storage.”
Current status and future market
The global fleet of large-scale CO2 carriers is still at an early stage.
By early 2025, two vessels dedicated for specific CCS projects have been delivered and gone into operation, with two more under construction. More vessels are expected to follow over the coming years.
Future LCO2 carriers are expected to fall into three main categories: short sea trading with vessels up to about 20k m3, offshore injection projects with vessels up to 50k m3 (also involving dedicated offshore units), and vessels for long-haul trades typically for the Asia-Pacific market transporting CO2 from Korea and Japan to permanent storage in countries like Malaysia, Indonesia, and Australia.
With the EU targeting an annual CO2 injection capacity of 50 million tonnes by 2030, and other countries like Korea and Japan also having ambitious targets for CCS, the need for CO2 carriers and supporting maritime infrastructure is expected to grow significantly in only a few years.
Looking forward, CCS capacity additions are projected to more than quadruple to 270 MtCO2/year over the next five years, with even stronger growth expected through to 2040 and 2050. This will need to be mirrored by growth in the CO2 carrier fleet.
As this new fleet of CO2 carriers develops, it is crucial that the transport cost aligns and reinforces the economic case for CCS as a viable alternative to “business as usual” for emitters.
CO2 as cargo
The physical properties of CO2 differs from other liquefied gases transported at sea. Its density is higher than other commonly traded liquefied gases such as LPG and LNG. Moreover, CO2 cannot exist in liquid form at atmospheric pressure. Pure CO2 has a triple point at 5.12 bara and -56.6°C, meaning it must be kept above this pressure and within a specific temperature range to remain in its liquid state. These factors create new challenges for the ship and cargo tanks, and need to be taken into consideration during design, construction, and operation.
While the relevant pressure and temperature are separately not extreme in any way, the combination poses challenges. In addition, the high weight of the cargo leads to high dynamic loads which create significant challenges in terms of fatigue.
CO2 from industrial emitters also contains different types of impurities, which can create a corrosive environment and influence the physical properties of CO2. A structured approach to manage the risks associated with the CO2 composition is a new but important element for this new shipping segment.
Read the white paper: DNV CO2 Shipping - Design, safety, and regulatory considerations for an emerging fleet