Climate change will once again be the subject of public discussion next November as part of the 26th Conference on Climate Change of the United Nations (COP26) in Glasgow. The record-breaking number of extreme weather events in the summer of 2021, with floods, droughts, forest fires and hurricanes, has provided a taste of the future negative effects of global warming.
The main driver of this global warming is the rapidly increasing concentration of carbon dioxide (CO2) in the atmosphere. CO2 accounts for 74.4 percent of global greenhouse gases (measured by global warming potential, which is significantly higher for methane, for example). If the negative effects of global warming are to be contained, reducing CO2 emissions is an absolute necessity.
Carbon capture and storage is technologically practical
A large part of the CO2 reduction path to reach the Paris climate goal can be achieved with renewable energies, energy efficiency gains and increasing electrification. But only one part of it. The International Renewable Energy Agency (IRENA) estimates that around 6 to 10 percent of CO2 is emitted in areas where emissions are very difficult or even impossible to avoid – for example in cement and steel production. Carbon capture, utilisation and storage (CCUS) is seen by experts as a technologically effective method of removing CO2 in a wide range of sectors.
Use of this technology is possible and already in practice
CCUS involves the capture (or filtration) of CO2 from a number of sources (including air) and transport by pipeline or ship for utilisation or permanent storage (see diagram). The technology is already being used in power generation and in industrial plants that use fossil fuels or biomass, such as those that produce hydrogen. Captured CO2 can be used on site or transported in compressed form. For instance, it can be used to produce synthetic aircraft fuel or permanently stored in geological formations such as exhausted oil and gas deposits.