CII AND CCS: A QUICK ROUTE TO 2050

Will IMO acknowledge carbon capture’s potential in reducing a ship’s carbon intensity?

Paul Gunton reports

At first sight, carbon capture and storage (CCS) seems an obvious factor to take into account when calculating a ship’s Carbon Intensity Indicator (CII): it reduces a ship’s carbon emissions and thus its carbon intensity. But it is not currently included in the calculation, although momentum is building for that to be reviewed and IMO’s Marine Environment Protection Committee has it on its agenda..

CII came into effect on 1 January 2023 to provide a measure of a ship’s efficiency in terms of its emitted CO2 per cargocarrying mile, using fuel consumption as the main parameter for calculating how much CO2 is emitted. The notion that there could be a technology that retains some – perhaps most – of those emissions onboard, was not taken into account.

One company that makes such equipment is Wärtsilä and a comment to The Motorship by its director of exhaust treatment, Sigurd Jenssen, gives a clue about its omission. The company looked at CCS a decade ago and “didn’t really think this was doable. But we’ve changed our minds”, he said.

He believes that legislators have been on the same journey as they developed greenhouse gas (GHG) strategies. They began with energy efficiency, voyage optimisation and lowcarbon fuels, but their views have matured to take a more holistic view, he said. “Then, carbon capture easily comes into the picture.”

It is easy to see why CCS might not seem an attractive route towards tackling emissions. The captured CO2 weighs about three times that of the fuel burned, which will have an impact on a ship’s displacement during a voyage; the collection machinery requires a significant amount of fuel (estimates vary, but 10-20% of installed power are typical figures); CAPEX and OPEX will increase; offloading and onshore storage complicate discharge calls; and monitoring and confirming that the CO2 is actually permanently locked away – or transferred to a re-use facility – will add regulatory burdens.

On the other hand, IMO’s Initial GHG strategy includes two related ambitions that share a 2050 goal: to cut annual GHG emissions from international shipping by at least half and to aim to reduce the carbon intensity of international shipping by 70%, both compared to 2008. With carbon capture, “you can essentially reach 2050 targets today”, Mr Jenssen said.

Not only that, but this delivers a much greater total emissions reduction between now and then that could be achieved by the 2-3% per year reduction envisaged by the current CII reduction curve. On that basis, CCS “would enable a much more aggressive reduction in emissions”, he added.

MEPC discussions

It was the Republic of Korea that first brought CCS to MEPC’s attention, in a paper submitted for MEPC 76 in June 2021, although scheduling pressures led to it being held over for a year, to MEPC 78, for discussion.

Korea’s paper made the same point as Mr Jenssen: “now is a timely stage for introducing measures for onboard CO2 capture so as to promote the adoption of innovative CO2 reduction technologies as well as provide the opportunity to reduce CO2 emissions … to meet the goals set by the Initial Strategy at the earliest possible moment”, its paper argued. It also noted that EEDI/EEXI calculations should also take account of the impact of CCS.

Discussions at that meeting included views both in support and with concerns about the proposal and the committee asked for “further information and concrete proposals” to be submitted to future sessions.

The result was six submissions on the topic at MEPC 79 in December 2022, including one by Norway. It called on MEPC to set up a dedicated work stream to consider the use of CCS technology, with three terms of reference. First, it should review the status of technological development of onboard carbon capture applications; second it should identify possible options for the accounting, verification and certification of captured CO2; and consider how to incorporate onboard carbon capture into IMO’s regulatory framework.

Lloyd’s Register’s lead decarbonisation consultant, Brijesh Tewari, drew The Motorship’s attention to a particular section of that paper, which suggested that “for the calculation of the CII, the accounting might be easier as the actual mass of CO2 delivered to a certified transport network could be used … [and be] potentially subtracted when calculating the emissions of the ship.” The paper also suggested that “the same approach can be used in a market-based measure such as an emission trading scheme or a levy-based system if developed.”

In that section of the paper, Norway also identified “a need for stand-alone guidelines regarding the verification of systems relating to the performance, the characterisation of the carbon dioxide stream and possibly a recognised certification scheme for environmentally safe permanent storage.” This, it said, could require amendments to MARPOL Annex VI.

Korea also submitted a paper to MEPC 79, in which it noted that CII, EEDI and EEXI calculations are based on tank-to-wake (TtW) methodology, while IMO’s draft Lifecycle Assessment (LCA) guidelines apply a well-to-wake (WtW) approach. It pointed out this inconsistency and said that “onboard CO2

8 We’ve changed our minds” about carbon capture, says Sigurd Jenssen capture can be included only in IMO GHG regulations based on WtW methodology.”

No decisions were taken on how to incorporate CCS into CII, EEDI or EEXI during MEPC 79, “owing to time constraints”, the meeting’s summary reported. Instead, MEPC agreed “to further consider proposals related to onboard CO2 capture” at MEPC 80, which will take place 3-7 July.

“This means that the documents already submitted are kept alive, which is important”, commented Eirik Nyhus, DNV’s environment director, in conversation with The Motorship. He is also a member of Norway’s IMO delegation and is concerned that there will be little time during that meeting to discuss it in depth, because that meeting will have a busy agenda. It is possible, he said, that the topic could be moved on to the next intersessional meeting or to MEPC 81, which will take place in 2024.

Even if it is discussed during MEPC 80, no firm decisions will be taken on how to apply CCS, Mr Nyhus believes. Not only does it present technical challenges, “but there’s also the issue of what happens with the CO2 once it gets delivered to shore”, he said. “We do not want to see it vented outside the port gates, so environmental integrity is a crucial point.”

CO2 recycling

Another potential destination for captured carbon could be to use it as a feedstock for making renewable methanol or ammonia, something that would also have to be considered in any WtW calculation and the LCA guidelines, he suggested, since “if you use recycled carbon, there is a potential that would reduce [those fuels’] production footprint.”

It is not only fuel production that would benefit from captured CO2. A submission by Liberia and the International Chamber of Shipping included a list of industries that can use the gas, such as the fertiliser sector, which they say uses 130Mt per year. Oil and gas processors use 70-80Mt/year for enhanced oil recovery, the paper noted, while other commercial applications include food and beverage production, metal fabrication, cooling, fire suppression and stimulating plant growth in greenhouses.

Asked whether shipowners might gain some form of carbon credit for delivering CO2 for recycling, Mr Nyhus said that this had not been discussed and “it would be really horrendously complicated to make such a system work.” He did not rule out some kind of market-based measure including CCS eventually being developed, but “that is for the post-MEPC 80 era.” A more likely outcome, he suggested, would be that companies would reflect such actions as part of their voluntary Environmental, Social and Governance (ESG) policies.

CII is due to be reviewed in 2025, with adjustments made if necessary to keep the industry on track towards hitting the 2050 target of reducing GHG emissions by 70%. So any changes to its formulation to take account of CCS may not be introduced until then, Mr Nyhus believes. In the meantime, CCS may eventually be addressed through IMO’s LCA guideline. While the first version is expected to be approved at MEPC 80, incorporating CCS may have to wait until a later version he suggested.

That will not be the end of the debate, however. “We still need to have the political discussion at IMO about how, and to what extent, should that guideline be applied to existing and future regulations.” Resolving that could take until 2025, he said. “We are eating the elephant in very thin slices.”

Do shipowners want to use CCS?

While IMO grapples with the technical and regulatory aspects of adopting onboard carbon capture and storage (CCS), it remains to be seen whether shipowners will embrace the opportunity.

We are planning to, says gas tanker operator Solvang. No, we probably won’t, says car carrier specialist Wallenius Wilhelmsen.

Solvang is one of several shipowners working with Wärtsilä Exhaust Treatment to deploy CCS technology and intends to install a full-scale pilot retrofit on one of its ethylene carriers, the 21,000m3 Clipper Eos. Wärtsilä has already built a land-based 1MW test system at its Norwegian headquarters and plans to fit the ship’s system this year.

When the contract was announced in 2021, Solvang’s CEO Edvin Endresen said that CCS “could be an important key to decarbonise the world’s deep-sea fleet.” The vessel is time-chartered to Japan’s Marubeni Corp, which is “committed to cooperating with Solvang and Wärtsilä … in a mutual effort to drastically reduce the CO2 footprint of the vessel”, the 2021 statement said.

More recently, in November 2022, Wärtsilä secured its first order for CCS-ready 35MW open-loop scrubbers for four 8,200TEU container ships. Their owner and Asian yard have not been disclosed.

Wärtsilä’s head of exhaust treatment, Sigurd Jenssen, told The Motorship that interest in CCS “is massive. Every shipowner is keen to understand how this could be applied to their fleet.” It offers them a way of addressing emissions that is lessdisruptive than alternatives because of the amount of CO2 reductions that can be achieved, despite the cost and operational compromises required, he said.

For example, although additional tanks are required to store the CO2, the added volume is no worse than the additional volume required to store less energy-dense fuels such as LNG and methanol, and certainly better than storing ammonia or hydrogen, he said.

On the Solvang vessel, for example, two deck-mounted tanks will hold about 720m3 of CO2 that will be recovered by Wärtsilä’s carbon capture equipment, which will remove about 66% of the emitted gas. That is sufficient to support a transatlantic crossing and although the extra weight will affect cargo capacity, it is not enough to make the operation uneconomic, Mr Jenssen said.

But for Roger Strevens, vice-president of global sustainability at car carrier Wallenius Wilhelmsen, the 3:1 ratio between the weight of CO2 produced and fuel burned is a significant concern. Then there is the space needed both for storage and for the capture equipment: “We are volume carriers, constantly squeezing the engine, machinery and fuel into the smallest possible spaces,” he said.

He is also worried about operational impacts. Matching CCS-equipped ships to ports with suitable reception facilities would limit their scheduling flexibility and he foresees practical difficulties in discharging the stored material. “Our preference is to have no obstructions whatsoever on the berth” and offloading “several thousand tonnes of frozen CO2 is going to occupy some space.” In short, as things currently stand, “we don’t see very good prospects for carbon capture onboard our vessels,” he said. But CCS could work for other operators. Those providing short haul services with regular calls at their home port, for example, may find CCS an interesting solution, he said.