Carbon capture, utilisation and storage (CCUS)

Carbon capture, utilisation and storage (CCUS) is the set of technologies that capture carbon dioxide from industrial sources or directly from the air to use it in other processes or store it permanently, preventing it from reaching the atmosphere. The acronym captures two possible routes after capture: utilisation (CCU) and storage (CCS).

In capture, CO2 is separated from the flue gases of an industrial stack, from a process stream or from ambient air. From there, the utilisation route incorporates the captured CO2 into products or processes (synthetic fuels, building materials, chemicals), while the storage route injects and confines it in deep geological formations, such as saline aquifers or depleted reservoirs.

Difference from carbon storage

CCUS should not be confused with carbon storage in the broad sense, which also includes natural processes in soils, forests and oceans. CCUS refers specifically to the technological capture of CO2 and its subsequent management. When it captures CO2 directly from the air and stores it durably, it contributes to carbon removal; when it only avoids emissions from an industrial source, it acts as a reduction measure, not a removal.

Where it adds most value

The main interest in CCUS lies in hard-to-abate sectors, where emissions come from chemical reactions in the process itself and not only from energy use. This is the case for cement, steel and chemicals, where it is difficult to eliminate emissions through electrification or efficiency alone. In cement production, for example, much of the CO2 comes from the calcination of limestone, so capture is one of the few deep-reduction routes available.

These technologies complement, but do not replace, other net zero emissions levers such as renewable energy, efficiency or process change. They also relate to natural carbon sinks, although their logic is industrial.

EU regulatory framework

In the European Union, Regulation (EU) 2024/3012, known as the Carbon Removal Certification Framework (CRCF), set up a voluntary system in 2024 to certify permanent carbon removals, carbon farming and carbon storage in products. The geological storage of CO2 is also regulated by Directive 2009/31/EC. CCUS also interacts with the EU Emissions Trading System (EU ETS), which recognises permanently captured and stored CO2.

Limitations

CCUS faces significant challenges. It is capital- and energy-intensive, since the capture process consumes additional electricity or heat, reducing the net efficiency of the facility. Its deployment has been slower than expected and its role in energy scenarios is debated. It is therefore seen as a complementary tool, reserved mainly for residual emissions and processes with no clear alternatives, rather than a substitute for cutting emissions at source.

Reduce before you capture with Manglai

Before considering capture solutions, it is wise to measure and cut avoidable emissions. Manglai helps you quantify your footprint and prioritise the highest-impact reductions, leaving capture for the emissions that are genuinely hard to abate. Discover how Manglai can help you build your decarbonisation roadmap.