The technology behind capturing CO₂ was originally developed in the 1930s to purify natural gas. Only in recent years has it been recognised as essential for meeting the Paris Agreement goal of limiting global warming.   

While some action has already been taken to mitigate climate change, most efforts have focused on reducing emissions, e.g., by improving energy efficiency or electrifying processes with renewable electricity. However, to achieve the goal of climate neutrality, substantial amounts (gigatonnes) of CO₂ need to be removed from the atmosphere every year for decades to come. 

CO₂ from hard-to-abate sectors
In some sectors, often referred to as hard-to-abate sectors, it can be technically or economically challenging to fully decarbonise, as they currently rely heavily on fossil fuels for energy-intensive processes. Emissions from these industries are typically related to the physical processes themselves, such as cement production. By capturing CO₂ from these processes, it becomes possible to significantly reduce companies’ and sectors’ emissions, in some cases making them climate-neutral. Because many of these sectors heavily rely on fossil fuels for energy-intensive processes, green fuels can also play a central role in driving their decarbonisation. 

CO₂ from biogenic sources
Biogenic CO₂ comes from natural sources such as sustainable biomass, biogas, and organic waste. Since it is part of the natural carbon cycle, it does not add new CO₂ to the atmosphere. This makes biogenic CO₂ a valuable resource. It can be reused to produce climate-neutral products, thereby helping to reduce emissions in other sectors by avoiding extraction and use of fossil fuels. Alternatively, biogenic CO₂ can be permanently stored underground, creating negative emissions by removing CO₂ from the atmosphere. 

Denmark is well-positioned to lead the development and implementation of carbon capture due to many years of experience with bioenergy. In 2023, biomass and biogas together constituted 19% of the country’s electricity production. However, as demand for biogenic CO₂ grows, a future shortage could arise. 

Capturing CO₂ directly at the source is an important step towards climate neutrality and ultimately net-negative emissions. However, it is not enough on its own. New methods for removing CO₂ directly from the atmosphere must be developed and scaled within the next decade to supplement capture from emitters. Some of these emerging solutions will be explored in a later chapter.