Shipping line MOL has become the second ONE partner investing in direct air carbon capture and storage (DACC), with a deal announced with Climeworks.
The latest deal makes the carrier Climeworks’ first shipping customer, and first Japanese customer. DACC will be used to remove 13,400 tonnes of atmospheric CO2 by 2030, offset against that generated by MOL’s fleet.
According to data from Searoutes, a typical voyage between car terminals at Taicang and Bremerhaven would generate a 0.18-0.2 tonnes of CO2-equivalent per tonne of cargo. MOL is aiming for 2.2 million tonnes of carbon removal by 2030.
“Contributing the expansion of high-integrity carbon removal credits, powered by Climeworks’ state-of-the-art direct air capture technology, allows us to take responsibility for emissions that are hard to eliminate through traditional means,” said Hisashi Umemura, MOL’s director general. “This is not just an investment in carbon removal, but in the future of sustainable shipping.”
Adrian Siegrist, chief commercial officer of Climeworks, added: “We seek strong, long-term partners like MOL, companies that recognise the scale of the climate challenge and the strategic opportunity of early action. This includes preferential access to carbon removal capacity and the chance to drive business innovation.
“Every company thinking about becoming a buyer today is well-positioned to propel this sector forward for their own benefit.”
A limiting factor in the application of carbon-capture applications is the high heat requirements of the process, meaning it is extremely energy-hungry, whether in the form of DACC, or capturing carbon from specific emitting sources such as power plants and ship funnels (‘point’-CCS).
This high energy requirement has proved a hurdle for ships’ onboard carbon capture (OCCS), as vessels need to burn a punitive proportion of additional fuel to generate sufficient heat for just a fraction of exhaust CO2 to be sequestered.
Current-generation DACC technology requires as much as 2.5MWh – the output of a large wind turbine – per tonne of CO2collected. To address this problem, Climeworks operates two DACC plants in Iceland, where the abundant supply of geothermal energy makes for a ready source of zero-carbon heat and electrical power. At 0.2 sq km per tonne of CO2 captured annually, DACC is substantially more space-efficient than the alternative, afforestation, which requires 862 sq km of forest area per tonne.
But the concentration of CO2 in ambient air is extremely low – around 0.04% – versus the high concentrations emitted from power plants and ships. Extreme differentials in CCS’s energy efficiency are possible using this principle.
Illustrating this, Edvin Endresen, Solvang CEO, explained how onboard CCS systems retrofitted on his tankers had been able to attain extraordinarily high efficiencies, compared with the OCCS state-of-the-art.
Commonly, around 30% of a ship’s CO2 exhaust is captured via a 50% increase in fuel consumption. However, according to Mr Endresen, Solvang managed to obtain around 60% and 20%, respectively, by installing an OCCS device on a ship already equipped with exhaust gas recirculation.
Apparently by accident, Solvang discovered that this NOx-reduction technology increased the concentration of CO2 in exhaust gas fed into the CCS, thereby massively increasing its efficiency.
“We have found that going between 30% and 50% [carbon captured], there is hardly any [increase in fuel consumption] – like 5%,” he explained. “But when you go past 60%, it climbs to 10%, 15%, and when you get close to 70%, you get a 15%, 20% increase in fuel consumption. After that, the curve goes really steep, because you need to apply much more heat to get the extra out of it.
“That’s why DACC systems, which capture carbon from ambient air, have such low efficiency,” he added.
Scientists agree that some form of CCS will be necessary to reverse the effects of climate change; but its opponents compare the technology to tackling an over spilling bathtub with a mop, arguing that CCS would be a waste of energy until all fossil fuel extraction is displaced by renewable power.
