Carbon Capture and Storage (CCS)
Introduction
Carbon capture and storage (CAC or CCS) is a technology to prevent carbon dioxide emissions into the atmosphere or remove it from it through direct air capture (DAC). CCS consists of separating the CO emitted by industry and energy generation in combustion processes, and transporting it to a geological storage site to isolate it from the atmosphere in the long term.
The chemical process of CO capture is energetically expensive and CO is probably produced during it. This process only delays the release of CO, which cannot be stored indefinitely. However, this CO could be used in multiple ways.
Although CO has been injected into geological formations for various purposes, long-term storage of CO emissions is a relatively new concept. The first commercial example is Weyburn in 2000; with an integrated CCS power production pilot plant, operating since September 2008 at the Schwarze Pumpe thermal power plant in Vattenfall, eastern Germany, with the aim of answering questions about technological feasibility and economic efficiency.
CCS applied to a modern conventional power plant could reduce CO emissions to the atmosphere by approximately 80-90% compared to a plant without CCS.[1] The IPCC estimates that the potential savings from CCS could be between 10% to 55% of total carbon mitigation until 2100.[1].
Capturing and compressing CO is energy intensive and would increase the fuel needs of a CCS coal plant by 25-40%[1] These and other system costs are estimated to increase the energy cost of new CCS power plants by 21-91%.[1][2].
The storage of CO is predicted to be in deep geological formations, in deep water bodies, or in the form of carbonate minerals. In the case of deep ocean storage, there is a risk of greatly increasing the problem of ocean acidification, a problem that also arises from the excess carbon dioxide already present in the atmosphere and oceans. Geological formations are currently considered the most plausible sites for carbon sequestration. In its 2007 Carbon Sequestration Atlas, the National Energy Technology Laboratory reported that North America has enough storage capacity for 900 years of carbon dioxide production.[3] A general problem is that long-term predictions about safe underwater or underground storage are very difficult and uncertain, and the risk remains that CO could leak from storage into the atmosphere.
When applied to plants that use biomass, the process is known as bioenergy with carbon capture and storage. This has the potential to be used as a negative carbon emissions technique, and is considered by some as geoengineering.