What are carbon removals?

Quick Answer: Carbon removals are processes that extract carbon dioxide (CO2) from the atmosphere and store it durably, either through natural systems or engineered technologies. They are distinct from emissions reductions, which prevent CO2 from entering the atmosphere in the first place. Carbon removals are increasingly referenced in net zero frameworks as a tool for addressing residual emissions that cannot be eliminated through operational changes alone.

What are carbon removals?

Carbon removals are activities that actively draw down CO2 that is already in the atmosphere and store it in a stable form, whether in soil, biomass, geological formations, or materials. The term is sometimes used interchangeably with "carbon dioxide removal" (CDR) or "negative emissions."

The distinction from emissions reductions matters. Reducing emissions means producing less CO2 to begin with, for example by switching to renewable energy or cutting business travel. Removals address what is already there. Both are necessary in credible net zero pathways, but they serve different functions and are not substitutes for one another.

The Intergovernmental Panel on Climate Change (IPCC) has consistently stated that limiting global warming to 1.5°C will require significant carbon dioxide removal alongside deep emissions cuts. The IPCC Sixth Assessment Report (2022) found that all modelled pathways to 1.5°C involve some form of CDR.

What are the main types of carbon removal?

Carbon removals fall into two broad categories: nature-based and technology-based. Each has different cost profiles, permanence characteristics, and levels of scientific maturity.

Nature-based removals

Nature-based removals use biological processes to absorb and store CO2. Common examples include:

• Reforestation and afforestation — planting trees or restoring forests to absorb CO2 as they grow. One of the most widely used removal approaches.
• Soil carbon sequestration — improving agricultural practices (cover cropping, reduced tillage, compost application) to increase the amount of carbon stored in soil.
• Wetland and peatland restoration — restoring degraded peatlands and coastal wetlands, which are among the densest natural carbon stores per hectare.
• Blue carbon — conservation and restoration of coastal ecosystems such as mangroves, seagrass, and saltmarsh, which sequester carbon in both biomass and sediment.

Nature-based removals are generally lower cost and can deliver co-benefits such as biodiversity and water quality improvements. The trade-off is permanence. Forests can burn, be logged, or be affected by disease, releasing stored carbon back into the atmosphere.

Technology-based removals

Technology-based removals use engineered processes to capture and store CO2. Key examples include:

• Direct air capture (DAC) — machines that pull CO2 directly from ambient air and compress it for storage, typically in deep geological formations. Currently the highest-cost removal method but offers high permanence.
• Bioenergy with carbon capture and storage (BECCS) — burning biomass for energy while capturing the resulting CO2 emissions and storing them underground, theoretically achieving negative emissions overall.
• Biochar — converting organic material into a stable charcoal-like substance through low-oxygen heating, which is then incorporated into soil where it can store carbon for centuries.‍
• Enhanced weathering — spreading crushed silicate rock on agricultural land to accelerate natural mineral reactions that draw down CO2, with the added benefit of improving soil fertility.

Technology-based removals tend to offer greater permanence, particularly where CO2 is stored in geological formations. The challenge is cost and scale. DAC currently costs between $300-$1,000 per tonne of CO2 removed (IEA, 2023), making it expensive relative to nature-based alternatives, though costs are expected to fall as the technology matures.

Why do carbon removals matter for net zero targets?

Net zero means reaching a point where the greenhouse gases a company (or country) puts into the atmosphere are balanced by the amount removed. In practice, most organisations will reach a point where further emissions reductions become technically or economically very difficult. These are called residual emissions, and carbon removals are the accepted mechanism for balancing them out.

The Science Based Targets initiative (SBTi) Corporate Net-Zero Standard requires companies to reduce their emissions by at least 90% before using carbon removals to neutralise the remaining 10%. This is a deliberate design choice: removals are not intended to replace the work of decarbonisation, but to address what remains after that work is done.

This framing is important for anyone building a credible decarbonisation plan. A company that offsets its way to a "net zero" claim without reducing its operational emissions is not meeting the standard that SBTi or the GHG Protocol recognises. Carbon removals have a legitimate and necessary role, but only in the context of a genuine reduction trajectory.

How do carbon removals differ from carbon offsets?

The terms are related but not identical, and the difference matters in a compliance context.

Carbon offsets is a broader term that covers any credit representing a tonne of CO2 avoided or removed. This includes avoidance credits, where a project prevents emissions that would otherwise have occurred (for example, protecting a forest from deforestation). Avoidance credits do not remove any CO2 from the atmosphere; they simply reduce the rate at which new emissions are added.

Carbon removals specifically refer to activities that take CO2 out of the atmosphere. Removal credits are therefore considered higher quality in most frameworks because they address existing atmospheric concentrations rather than simply slowing the rate of increase.

Increasingly, corporate net zero standards are moving away from accepting avoidance-based offsets for neutralisation claims. The Oxford Principles for Net Zero Aligned Carbon Offsetting (University of Oxford, 2020) recommend that companies shift over time towards high-quality carbon removals with durable storage, and away from avoidance-based credits.

For companies working towards SBTi-aligned targets, understanding this distinction is practically relevant. Offsets used to claim neutralisation of residual emissions should be removal-based, not avoidance-based, to withstand scrutiny from stakeholders and reporting frameworks.

What should businesses understand about carbon removals right now?

For most businesses, carbon removals are not an immediate operational concern. The priority at this stage is measuring your full carbon footprint accurately, identifying your largest emission sources, and building a reduction plan. Removals become relevant later in that journey, when residual emissions need to be addressed.

That said, a few things are worth understanding now:

• The quality gap is wide. Not all removal credits are equal. A tonne removed via verified geological storage is fundamentally more durable than a tonne stored in a forest with no long-term protection. The price difference reflects this, and so does the scrutiny from frameworks like SBTi.
• Voluntary markets are maturing but remain inconsistent. Standards such as Puro.earth, Verra's VCS, and Gold Standard are developing more rigorous methodologies for removal credits, but due diligence is still required before purchase.‍
• Removals are becoming a forward planning consideration. As SBTi and other frameworks require companies to account for residual emissions in their net zero targets, understanding the likely cost and availability of high-quality removals over a 10-20 year horizon is increasingly part of responsible decarbonisation planning.

Seedling's decarbonisation planning support helps companies understand where removals fit within a broader, quantified net zero plan, rather than treating them as a shortcut to a headline claim. The role of removals is to close the gap that genuine reduction cannot close, not to paper over it.