Cleaner LNG use

LNG is widely seen as a stepping stone to zero-emission port and shipping operations, but new research has found the use of carbon capture and storage (CCS) could have a material impact on LNG projects’ carbon emissions, meaning it could have more scope for longer term use.

“Depending on the strategy adopted, more than 25% of overall carbon emissions could be removed,” said research and consultancy business, Wood Mackenzie.

Daniel Toleman, senior analyst at Wood Mackenzie, explained: “The main options for reducing LNG emissions include CCS, carbon offsets, methane leakage reduction, electrification, and the use of renewables and batteries. CCS can have a material impact on reducing emissions of LNG projects. Depending on the CCS strategy adopted, we estimate that more than 25% of carbon emissions can be removed.”

He added: “The good news is that LNG players are well placed to lead the CCS charge, with strong balance sheets, operational capability and reservoir expertise. There are also economic incentives for pursuing CCS as reducing emissions mitigates against a carbon tax, helps future-proof the asset and can offer pricing upside.”

Deploying CCS at LNG projects

There are two main approaches to deploying CCS at LNG projects: capturing CO2 from the reservoir and capturing post-combustion CO2.

Approach one involves capturing reservoir CO2. There are significant cost advantages to this approach versus post-combustion capture. Irrespective of whether reservoir CO2 is sequestered or vented, all LNG projects must remove CO2 from the feedgas stream before liquefaction to prevent the CO2 from freezing and blocking processes. As such, the acid gas removal unit (AGRU) used to capture CO2 does not incur additional costs. Reservoir CCS can reduce the overall intensity of LNG projects by 25%, and in some cases up to 50%.

In contrast, the second approach, post-combustion CCS, involves capturing CO2 from the LNG flue gas stream. Post-combustion CCS is more expensive compared to reservoir CCS. However, there are cost benefits of adding post-combustion CCS to a new-build LNG facility, due to design and location synergies.