Direct Air Capture (DAC) is a technology designed to remove carbon dioxide (CO2) directly from the ambient air. Unlike traditional carbon capture, which targets high-concentration emissions from point sources like power plants, DAC addresses the diffuse CO2 already in the atmosphere. The process typically involves large fans moving air over a filter or chemical solution that selectively binds with CO2. The captured CO2 is then released in a concentrated stream, which can be permanently stored underground (sequestration) or used to create products like synthetic fuels or building materials.
The concept of capturing CO2 from the atmosphere was proposed by physicist Klaus Lackner in the late 1990s. Early research and development led to the formation of the first DAC companies in the late 2000s. The first commercial-scale DAC plants, such as Climeworks' 'Orca' facility in Iceland, began operations in the early 2020s, marking a significant step from theory to practical application.
DAC is increasingly recognized by bodies like the International Energy Agency (IEA) as a crucial tool for achieving 'net-zero' and 'net-negative' emissions targets, especially for balancing hard-to-abate sectors. Major companies in the field include Climeworks, Carbon Engineering, and Global Thermostat. Despite its potential, widespread deployment faces significant hurdles, primarily the high energy consumption and cost per ton of CO2 removed, which remain major areas of research and innovation.