CCS stands for Carbon dioxide Capture and Storage. CCS refers to the capture of CO2 from point-emission sources, such as waste-to-energy, chemical, or cement plants, and permanent storage in underground geological formations or in building materials (e.g. concrete). The source of the CO2 captured thereby can be of fossil or biogenic origin (s. Q 2).
In DemoUpCARMA, we focus on and distinguish two specific CCS approaches, which are referred to as CCUS (Carbon dioxide Capture, Utilisation and Storage) and CCTS (Carbon dioxide Capture, Transport and Storage). In these two acronyms, the letters “U” and “T” are added to emphasize the “utilization” and “transport” components of these two approaches.
CCUS involves three steps: (i) CO2 capture from point-emission sources, (ii) utilization of CO2 as a feedstock to produce a range of products, such as concrete, methanol, ethanol, carbonates, plastics etc. DemoUpCARMA investigates a CCUS pathway that optimizes permanent CO2 storage in building materials, i.e., recycling concrete. In DemoUpCARMA, a CCUS pilot is investigated and demonstrated, in which biogenic CO2 captured at a biogas plant is utilised and stored in concrete that is then used as a building material.
Similarly, CCTS involves three steps: (i) CO2 capture from point-emission sources, (ii) transportation of CO2 by truck, train, ship/barge, or pipeline, and (iii) permanent CO2 storage in a geological reservoir. In DemoUpCARMA, a CCTS pilot is investigated and demonstrated, in which biogenic CO2 captured at a biogas plant is transported from Switzerland to Iceland, where it is dissolved in seawater and stored underground in a basalt formation.
If CCUS or CCTS approaches are based on fossil CO2 (e.g., CO2 captured from a chemical plant), they result in CO2 emissions being avoided. On the contrary, if CCUS or CCTS approaches are based on biogenic CO2 (e.g., CO2 captured from a biogas plant), negative emissions are generated (CO2 removal). In the latter case, the CCUS or CCTS application would be categorized as a negative emission technology (NET; for details, see Q4). This also applies to the two DemoUpCARMA pilots outlined above.