GS Paper III

News Excerpt:

Recently, the German Economy Minister said that Berlin will allow sub-seabed storage of CO2 produced in certain industries in order to reach its goal to be carbon neutral by 2045.

More about the news:

• According to the German Economy and climate minister,Germany is making good progress with expanding renewable energy sources and usage, but a solution is needed for the carbon dioxide emitted by some sectors such as the cement industry that are hard to abate.
• He also proposed “carbon management strategy,” which needs to be turned into detailed legislation, foresees enabling the transport of carbon dioxide and its storage under the sea in Germany’s exclusive economic zone, except in marine conservation areas. 
• This strategy doesn’t foresee allowing storage sites on land, but that could be considered later if German state governments approve.
• Environmental group Greenpeace have complained about this issue that the German plans “bear the mark of the energy industry and heavy industry” and would allow even industries for which  there are “climate-friendly solutions” to carry on as they have to date.

What is carbon capture and storage (CCS):

• The main way to reduce CO2 emissions from large industrial sources is called carbon capture and storage, or CCS. 
• CCS involves capturing carbon dioxide (CO2) at emission sources, transporting and then storing or burying it in a suitable deep, underground location. 
• CCS can also mean the removal of CO2 directly or indirectly from the atmosphere.
• CO2 can be captured from large sources, such as power plants, natural gas processing facilities and some industrial processes. Capture from the open atmosphere is also possible.

Removal or collection of CO2:

• Where fossil fuels are burnt at power plants, there are three techniques to remove or ‘scrub’ CO2:
• Post-combustion: In this process, CO2 is removed after burning the fossil fuel. CO2 is captured (‘scrubbed’) from the exhaust (or ‘flue’) gases. 
• Pre-combustion: This technique traps CO2 before burning the fossil fuel. First, the fossil fuel is partially burned in a ‘gasifier’ to form synthetic gas. CO2 can be captured from this relatively pure exhaust stream. 
• Oxyfuel combustion: In oxyfuel combustion, the fossil fuel is burned in oxygen instead of air. The resulting flue gas consists of mainly CO2 and water vapour.

Transportation of CO2:

• After capture, CO2 must be transported to suitable storage sites. Pumping it though pipelines is the cheapest form of transport and is a well known and reliable technology.
• However, the increased number and carrying capacity of pipelines needed for a large-scale CCS industry will require further studies of pipeline safety, particularly in heavily populated areas or areas of high earthquake activity.
• Ships and road tankers can also be used to transport CO2 for small scale applications.

Storage of CO2:CO2 can be stored in two main ways: 

• Deep geological storage: Deep ocean storage will increase ocean acidification, a problem that also stems from the excess of CO2 already in the atmosphere and oceans.

• Geological formations are currently considered the most promising storage sites. Areas such as the North Sea and the US Gulf Coast are believed to contain a large amount of geological storage space.
• The Intergovernmental Panel on Climate Change (IPCC) says that for well-selected, well-designed and well-managed geological storage sites, CO2 could be trapped for millions of years, retaining over 99 per cent of the injected CO2 over 1000 years.

• Mineral storage: In mineral storage, captured CO2 is reacted with naturally occurring iron (Fe), magnesium (Mg) and calcium (Ca) minerals. 

• This is called ‘mineral carbonation’ and occurs naturally in the weathering of rock over time. Such minerals are very abundant and very stable. As a result, the re-release of CO2 into the atmosphere does not happen.
• However, these carbonation reactions are very slow under normal conditions and to speed it up would need energy to increase temperature and pressure to ideal levels.
• The IPCC estimates that a power plant equipped with CCS using mineral storage will need 60–180 per cent more energy than a power plant without CCS.

Conclusion:

Germany's decision to allow carbon capture and underwater storage reflects a commitment to achieving carbon neutrality by 2045. While facing criticism from environmental groups, the strategy acknowledges the need for solutions in hard-to-abate sectors. Implementing CCS technologies presents challenges but offers a pathway towards reducing CO2 emissions.