TR EN

Evidence base

Carbon Removal Technologies

Durable carbon removal is grouped here into eight categories: direct air capture, biochar, BECCS, BiCRS, enhanced rock weathering, mineralization, ocean-based methods and geological storage. Each category page sets out what the durability claim rests on and whether the region has anything to match it.

All eight pathways are intended to store carbon for centuries to millennia.

Eight categories, eight separate assessments

  • Direct Air Capture

    DAC/DACCS

    Direct air capture is a family of systems that pass atmospheric air over a sorbent or through a solvent, bind the CO2 chemically, and store the concentrated gas geologically.

  • Biochar

    Biochar is the porous, stable solid carbon left when biomass is heated in the absence of oxygen.

  • Bioenergy with Carbon Capture and Storage

    BECCS

    BECCS captures the CO2 released when biomass is converted to energy and stores it geologically.

  • Biomass Carbon Removal and Storage

    BiCRS

    BiCRS is a family of methods that ties the carbon biomass took from the air to a store it will not return from: the biomass is either kept whole in conditions that halt decay, or processed so that its carbon moves into a geological or mineral store.

  • Enhanced Rock Weathering

    ERW

    Enhanced rock weathering spreads crushed silicate rock on land or coastline to accelerate a natural weathering reaction.

  • Mineralization

    Mineralization is the reaction of CO2 with calcium- and magnesium-bearing rock to form solid carbonate.

  • Ocean-based Removal

    Ocean-based removal is a family of methods that accelerate oceanic CO2 uptake by raising alkalinity or by helping marine life carry carbon into deep water.

  • Geological Storage

    Geological storage injects compressed CO2 into porous formation at 800–2,500 metres depth, where an impermeable seal holds it in place.

Frequently asked questions

How many categories of carbon removal technology are there?

This site groups durable carbon removal into eight categories: direct air capture, biochar, BECCS, BiCRS, enhanced rock weathering, mineralization, ocean-based methods and geological storage. Each category page sets out its technology types, application areas and deployment routes one by one.

Does geological storage count as carbon removal on its own?

It does not. Geological storage is a storage step: it produces a removal only when the CO2 it stores came from the atmosphere or from biomass. Injecting a fossil CO2 stream into the same formation is an emission reduction, not a removal. Mineralization depends on the route: when reactive materials such as mine tailings bind CO2 directly from the air, the result is a removal; when a captured CO2 stream is turned into carbonate, the result depends on where that CO2 came from.

Why are biochar and BECCS treated separately from BiCRS?

In the broad definition both belong to BiCRS: biochar and BECCS each store carbon that biomass took from the air. CDR Türkiye treats them as separate categories because the technology types and applications of each are varied enough to need their own page. The BiCRS page covers the remaining routes: burying or storing biomass, bio-oil injection and biogenic mineralization.

How are durability claims compared?

What decides the comparison is not the durability figure but what it rests on. For mineralization, durability was measured in the field; for most ocean-based methods it was calculated or modelled. Both can speak of long-term storage, and the evidence behind them does not carry equal weight.

Which of these categories can be deployed in Türkiye?

There is no established carbon removal supplier market in Türkiye, and no category is a proven advantage. Some of the inputs are present: agricultural and forestry residue, basalt and other magnesium-rich rock, geothermal resource, steel slag and coal fly ash. The difference lies in the evidence: having an input is not the same as having tested it, and the category pages state type by type where no verified data exists.

Does this assessment cover Türkiye only?

It does not. The supplier base is regional: Türkiye together with the Mediterranean basin, the Middle East and the Turkic Republics, with the aim of a region that produces durable carbon removal and exports it. A regional claim only stands once a method’s own measurement problem is settled, which is why the enhanced rock weathering and ocean-based pages say so plainly.