When commercialised, ship-based CCS could reduce CO2 emissions from ships, providing a bridge to alternative fuels, but multiple challenges must be overcome before the technology becomes mainstream
Using ship-based carbon capture and storage (CCS) technology would reduce CO2 ship emissions from existing ships to help with the transition to carbon-neutral fuels, but the technology is still years away.
Noting ship-based CCS as a potential bridging technology, Conoship International director of development Guus van der Bles said LNG-fuelled vessels would significantly benefit from its use, and said that, contrary to the World Bank’s point of view: “LNG-driven vessels are not a stranded asset.”
Burning LNG instead of traditional bunker fuels – HFO and marine diesel oil – significantly improves a ship’s emissions profile, reducing NOx emissions by about 80–85%, CO2 emissions by 20-25%, while virtually eliminating SOx and particulate matter.
Speaking on a panel at Riviera Maritime Media’s How ship-based CCS supports the transition to future fuels webinar, Mr van der Bles said with the possibility of integrating CCS technology in the future, combined with the progress being made by engine designers on reducing methane slip, LNG “is a good starting fossil fuel. That’s really important to grasp.”
One of the biggest concerns about LNG-fuelled vessels is methane slip, according to a poll of delegates: 57% selected 0.5-1% methane slip as the most harmful emissions from LNG-fuelled ships.
Methane is a potent greenhouse gas (GHG), with a global warming potential, 28-34 more times greater than CO2 over a 100-year timescale.
Part of Carbon Capture and Storage Webinar Week, the webinar was produced by LNG Shipping & Terminals and Marine Propulsion, with supporting organisations MARLOG and The Methanol Institute.
Mr van der Bles said the added benefit of using ship-based CCS was that the CO2 captured could be liquefied and stored on board for use as a feedstock to produce e-fuels or synthetic methane in a closed carbon loop, continuously reusing and recapturing carbon before it is released into the atmosphere. This would allow LNG-fuelled ships to become carbon-neutral, he said.
Joining Mr van der Bles on the panel were Maritime & Logistics Innovation Denmark (MARLOG) senior manager, green transition Jan Boyesen, Methanol Institute COO Chris Chatterton, and Potter Clarkson partner, patent attorney and energy & cleantech sector head Colin Baker.
“The uptake of both bio and renewable methanol is set to grow substantially”
While carbon capture utilisation and storage (CCUS) has been used on land for decades, it has yet to be scaled and marinised for shipboard use. Among its challenges are that it is space intensive, making it more difficult, for example, to employ on inland river vessels. Deep-sea vessels would require large storage tanks to hold the captured CO2 until they called at a port with reception facilities – which don’t yet exist.
Delegates were polled on their thoughts on the first on-board demonstration systems for ship-based CCS: 41% thought demonstration scale, 29% pilot scale, 19% full scale and 11% proof of concept scale.
With several ship-based CCS research projects under his belt, Mr van der Bles said ship-based CCS will be possible in three years and become mainstream on newbuilds in five years. His optimism was shared by three-quarters of the delegates in a poll regarding the speed of ship-based CCS uptake: 56% said ship-based CCS would enter the maritime mainstream in five years, 15% in one to two years and another 4% said it had already entered the mainstream. There is still scepticism in the market, with 20% responding it would enter the maritime mainstream in 10+ years and 6% saying it was never going to happen.
“There is a massive amount of CO2 emissions – about 1Bn tonnes from shipping,” said Mr Boyesen in discussing the two types of maritime carbon capture technology, amine and cryogenic. He called cryogenic carbon capture a “totally different technology,” that cools down the exhaust gas using heat exchangers in order to make the CO2 gas a solid.
Noting Denmark’s ambitious plans for reducing CO2 emissions from the transport sector, Mr Boyesen said: “There is going to be a need for carbon-containing fuels for the foreseeable future.”
Alluding to CCS supply chain development, he made the point that it would probably make more sense to produce these fuels using the CO2 captured as close to the emission sources as possible, to mitigate the costs involved in shipping it on CO2 carriers.
Mr Boyesen said MARLOG was working on a cryogenic carbon capture technology that could be used with existing fuels, MGO, HFO, LNG, biofuels or new fuels. He said the concept, decarbonICE, was to “freeze down the exhaust from ships and make it into CO2 dry-ice torpedoes.” As they are heavier than water, these dry-ice torpedoes would be discharged overboard, where they would naturally sink to the seafloor, penetrating the sediments to be stored permanently, primarily as CO2 hydrate.
Methanol has gained substantial attention in shipping, particularly following AP Møller-Maersk’s order for the first container vessel that will use carbon-neutral methanol as fuel when it begins operation in 2023.
GHG emissions can be avoided in the production of green methanol when made from biomass, waste streams and captured carbon dioxide emissions, making it a carbon-neutral or carbon-negative energy product.
Mr Chatterton said that according to The International Renewable Energy Association (IRENA): “The uptake of both bio and renewable methanol is set to grow substantially over the coming decades, with a considerable share of this methanol predicated on the use of carbon capture utilisation storage technology.”
“Dry-ice torpedoes would sink to the seafloor, penetrating the sediments to be stored permanently as CO2 hydrate”
Noting the carbon footprint differences between gray, brown, blue and green fuels, Mr Chatterton said: “Direct carbon capture from the atmosphere comes with a separate set of challenges. Within shipping, as we move to assess fuels on a lifecycle assessment basis, CCU technology is going to be even more vital.”
In joining the conversation, Mr Baker discussed the rapid development of new technologies and the protection of intellectual property (IP): “A patent can be applied to any CCS, provided it is new or an improvement; an improvement need only be incremental, in terms of carbon capture efficiency, fuel efficiency or ease of use.” He noted a misconception, that IP slows down innovation and the introduction of new technologies, saying: “There’s absolutely no need for that to be the case.”
In his conclusions, Mr Boyesen said: “It was interesting to learn that there seems to be a broad consensus that we need a carbon tax in order to get things running.” The EU plans to include shipping in its EU Emissions Trading System (ETS) starting in 2023 and phased in over a three-year timeframe.
This was highlighted in a poll in which delegates were asked to choose the fuel they would prefer to burn if they were building a new handsize bulk carrier, factoring in the future implementation of an ETS or carbon tax: 51% chose LNG, with the possible integration with ship-based CCS, 20% chose methanol, with future use of bio-methanol and synthetic e-methanol, 15% said they would hold off and order either a zero-emissions hydrogen or ammonia-fuelled vessel, whichever comes first, and 15% voted for ordering a low-sulphur heavy fuel oil bulk carrier and paying future carbon taxes.
“When it comes to whether CCS can support the long-term climate goals, I would say that one positive thing is that it can be carbon negative,” said Mr Boyesen. He said if used in combination with green methanol, for instance, and if the carbon is captured, “you will actually be reducing the content of CO2 in the atmosphere.”