Increased temperature on the earth due to CO2 emission is reality we confront. However, capturing and storing the CO2 could substantially reduce these emissions. According to International Energy Agency’s analysis, overall cost of emission reduction 2050 goals without it could increase by 70%.
Carbon capture and storage (CCS) involves CO2 capture, its compression and transport, as well as injection into deep geological formations. Not only that each stage of CCS is technically available, but also it has already been used commercially. Weyburn, Canada, in 2000 was the first example. Three methods are currently available for CO2 capture, namely, pre-combustion, post-combustion and oxy-fuel. High-pressure pipeline networks are predominantly used for transport. However, trucks, trains and ships have been used as well where infrastructure does not exist. With respect to its injection, possible solutions are saline formations, oil and gas reservoirs, as well as deep unminable coal seams. The greatest quantities of CO2 are expected to be stored in saline formations. Depth of 1000 m under the earth’s surface converts CO2 into liquefied state due to 9 bars pressure and therefore, reducing possible leakage. The question of safety has been rather controversial recently. Essential to be said here is that effective monitoring during the entire period of CO2 injection an beyond is provided. First, each storage site is examined thoroughly with the aim to ensure that it could store CO2 safely as well as to calculate its capacity. One of precondition is presence of, at least one, impermeable seal which would prevent CO2 from rising to the surface or reaching usable groundwater. Any possibility of triggering seismic activity is to be taken into account as well as particular physical and chemical processes which might take place during and after injection. These facts might be predicted with high degree of confidence using different seismic techniques. For instance, long-wavelength sound waves that travel through the earth might be generated. They are reflected by changes in layers, and then recorded as they return to detectors.
Under the BLUE Map scenario, 10 Gt of CO2 emissions is projected to be captured by global deployment of CCS in 2050 requiring around 3400 projects across the world! Capture from power generation would be 5.5 Gt CO2, from industry 1,7 Gt CO2 and upstream capture (during fuel and vehicle production) would account for 2.9 Gt CO2 of the total in 2050. The fact that costs involved must be reduced is the main priority for development of CCS. Furthermore, current issue is to prove that any loss would be insignificant so, it is important to demonstrate its credibility as a reliable and long-term store. Not only that developed world must lead in the field of CCS, but also the technology must be spread rapidly to the developing countries. It must be adopted by emissions-intensive industry, fuel transformation as well as gas processing sectors etc., having in mind that it is more than a strategy for ‘clean coal’.
Developing incentives for CO2 transport hubs and initiating regional planning cannot be done from other level but from the level of governments. What should kept in mind is the fact that possible leakage from CO2 storage sites into the atmosphere certainly would not cause worse climatic conditions than the case of direct emission!
Written by Ivana Letic
