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Carbon Capture and Storage (CCS)

While there is no silver bullet to eradicate the threat of global warming, one of the most promising technologies for rapidly reducing global emissions has been identified as Carbon Capture and Storage (CCS). A technology area that Shell is spearheading developments in.

The idea is simple, capture CO2 from power plants and refineries and store it safely underground. With a wide range of geologic variations around the world, however, a selection of technical solutions are needed.

For example, several storage possibilities exist. Storing CO2 in old oil and gas reservoirs, where the surrounding non-porous rock once contained the hydrocarbons for hundreds of millions of years is one approach. This option provides a second possible advantage, as well as being stored, the CO2 can be used to force out any remaining oil or gas from the reservoir (through enhanced oil recovery). Dissolving the CO2 in vast underground saltwater deposits known as saline aquifers, is another. In 2007, Shell and its partners began research in Germany in deep saline acquifiers - where CO2 is injected into a saline aquifer below a depleted gas field over several years.

Other possible options under study include storing CO2 in coal beds too difficult to be mined, where it will not only bond to the coal but will also displace natural gas, which can then be used as fuel.

Casestudy: CO2SINK

At Ketzin, just outside Berlin, Germany, Shell is co-ordinating monitoring of the subsurface storage of CO2 as a key part of the CO2SINK project. CO2SINK is a joint industry project between 18 different companies and institutes from 9 different countries and aims to develop the basis for CCS storage techniques by injecting CO2 into a saline aquifer. In particular, the project will: advance understanding of the science and practical processes involved in underground storage of CO2 in an onshore saline aquifer to reduce emissions of greenhouse gases to atmosphere, and build confidence towards future European carbon dioxide geological storage.

In June 2008, the project became the first in Europe to inject CO2 onshore. By the beginning of 2009, more than 8,000 tons of high-purity CO2 had been injected underground. Within the first two years, the total volume will be in the region of 60,000 tons - equivalent to the CO2 produced by around 30,000 cars in a year. The CO2 being stored is ‘food-grade’, the type used in drinks such as mineral water or beer.