Lexikon

carbon capture and storage (CCS), also mentioned as carbon capture and sequestration, is a means of mitigating the contribution of fossil fuel emissions to global warming, based on capturing carbon dioxide (CO2) from large point sources such as fossil fuel power plants, and storing it in such a way that it does not enter the atmosphere.

Storage of the CO₂ is envisaged either in deep geological formations, in deep ocean masses, or in the form of mineral carbonates. Geological formations are currently considered the most promising sequestration sites. Deep ocean storage has a risk of increased ocean acidification. Leakage of the underground storage places has also certain risk.

Although CO₂ has been injected into geological formations for various purposes, the long term storage of CO₂ is a relatively new concept. The first commercial example is Weyburn in 2000. Integrated pilot-scale CCS power plant was to begin operating in September 2008 in the eastern German power plant Schwarze Pumpe run by utility Vattenfall, in the hope of answering questions about technological feasibility and economic efficiency.

CCS applied to a modern conventional power plant could reduce CO₂ emissions to the atmosphere by approximately 80-90% compared to a plant without CCS.

Capturing and compressing CO₂ requires much energy and would increase the fuel needs of a coal-fired plant with CCS by 25%-40%. Estimates for 2025 say, that costs with CO₂ sequestration will not be higher, than without. (Source: Wikipedia)

Carbon capture and storage has also been used to describe biological capture by plants and microorganisms and subsequent storage of atmospheric CO₂, mainly in soil, and also in surface water sediments.

Biological sequestration involves the net removal of CO₂ from the atmosphere by plants and micro-organisms and its storage in vegetative biomass or structura organic matter. such as humus. Terrestrial carbon sequestration means the storage in storage in vegetative biomass and in soils.

Terrestrial sequestration applies agro- and forestry-technologies as well as ecoengineering tools and offers many potential advantages:

• could sequester relatively large volumes of carbon at comparatively low cost
• protecting or improving soils, water resources, habitat, and biodiversity
• generate rural income
• promotes more sustainable agriculture and forestry practices.