Without negative emissions, climate neutrality will not be achievable. According to a national research team, Germany needs a strategic research agenda, better models, clear policy frameworks, and forward-looking CO₂ infrastructure planning to ensure that CO₂ removal technologies can be deployed effectively, affordably, and in a socially sustainable manner.
Forests can also play a role when it comes to CO₂ removal methods.Copyright: Generated with AI
Germany will only achieve its climate protection goals if greenhouse gas emissions are consistently avoided and unavoidable residual emissions are offset by CO₂ removal from the atmosphere. This is highlighted in a new position paper by the Negative Emission Technologies Working Group within the System Analysis Research Network. The scientists, including Jülich-based systems researcher Dr. Thomas Schöb, advocate for incorporating negative emission technologies into the 9th Energy Research Program of the Federal Ministry for Economic Affairs and Energy (BMWE) and systematically investigating their role in the energy system.
Negative emission technologies are needed to offset unavoidable residual emissions and ensure climate neutrality.
Removing CO₂ – and storing it permanently
Negative emission technologies, or NETs for short, encompass technical processes used to remove CO₂ from the atmosphere or from biogenic sources and store it long-term. These include, among others, bioenergy with carbon capture and storage (BECCS) and direct air carbon capture and storage (DACCS). Nature-based approaches such as biochar or the enhancement of natural CO₂sinks on land or in the ocean round out the field of CDR (Carbon Dioxide Removal) methods. Long-term storage is crucial here: if captured CO₂ is merely used as a raw material and later released again, no permanent negative emissions are achieved.
“Negative emission technologies do not replace emission reductions. But they are needed to offset unavoidable residual emissions and ensure climate neutrality,” says systems researcher Dr. Thomas Schöb from Forschungszentrum Jülich. “To achieve this, we need robust system analyses, clear political frameworks, and early planning of the necessary CO₂ infrastructure.”
Learning from Pioneers
The policy paper identifies that Germany still has ground to make up in a European comparison. While countries such as Denmark and Sweden have already established concrete support mechanisms for CO₂ removal and storage, issues regarding funding, crediting, infrastructure, and systemic integration have not yet been sufficiently clarified in Germany. The authors of “ ” therefore recommend making greater use of international experience while simultaneously further developing European standards for the measurement, reporting, and certification of negative emissions.
What methods of CO₂ removal are available?
There are various approaches. Among the most frequently discussed are:
Afforestation & rewetting
Biochar
BECCS
DACCS
Accelerated weathering
Brief explanation
Forests, wetlands, or soils store more carbon
Keylimitation
Storage can be lost again due to fires, drought, or land use
Brief explanation
Biomass is processed into stable carbon
Key limitation
Effect depends on biomass source, application, and stability
Brief explanation
Biomass is used for energy, CO₂ is captured and stored
Key limitation
Only viable with sustainable biomass and long-term storage
Brief explanation
CO₂ is filtered directly from the air and stored
Key limitation
Requires a lot of renewable energy and suitable storage facilities
Brief explanation
Rock powder chemically binds CO₂
Key limitation
Many questions remain regarding scaling, environmental impacts, and verification
So there is no “one” solution. A mix of different methods will likely be necessary.
Clear Rules Against Greenwashing
According to the researchers, however, negative emission technologies can only contribute to climate protection if clear rules ensure their actual effectiveness. They must remove additional CO₂, complement rather than weaken natural sinks such as forests and soils, and be compatible with climate, nature, and food security goals. This requires targeted incentives, reliable verification, and funding that sensibly balances technical and natural solutions.
CO₂ removal requires energy, land, and infrastructure
Energy system analysis is of particular importance because technical methods for CO₂ removal are closely linked to the energy system: Direct air capture plants require large amounts of renewable energy, bioenergy-based technologies rely on biomass resources, and all storage-based methods require transport and storage infrastructure for CO₂. This creates synergies, such as through waste heat utilization, but also conflicts of interest, for example regarding land, biomass, or renewable electricity.
Models should show what really works
For negative emission technologies to be deployed effectively, research requires better models and robust scenarios. These must demonstrate which processes truly help under which conditions—not only in terms of costs, but also regarding sustainability, energy demand, infrastructure, land-use conflicts, and societal acceptance. This is particularly relevant for scenarios that look beyond the year of climate neutrality and explore energy systems that achieve net-negative emissions in the long term to stabilize the climate.
In addition, the impact of laws, funding programs, and incentive systems must be examined. After all, the development of negative-emission technologies is not merely a technical issue, but also a political and societal challenge. Transparent communication and early stakeholder engagement are crucial for the emergence of viable solutions.
Background
The paper was developed by the Negative Emission Technologies Working Group within the System Analysis Research Network, with the participation of Forschungszentrum Jülich. The network brings together scientific expertise for the analysis of energy systems and their transformation. The working group addresses the question of how technical processes for CO₂ removal from the atmosphere can be integrated into energy system models, climate strategies, and political decision-making processes.
Negative emissions occur when CO₂ is permanently removed from the atmosphere. The key word here is “permanently”: it is not enough to sequester CO₂ for only a short time or to release it again elsewhere. A true negative emission only exists when CO₂ is removed from the air and stored long-term—for example, in geological reservoirs, stable materials, soils, or biomass.
Negative emissions are not a substitute for climate protection. However, they can help offset unavoidable residual emissions and secure long-term climate goals. They cannot, however, replace the need for emissions to fall rapidly and significantly.
The simple formula is: as much emission avoidance as possible, as much CO₂ removal as necessary—and both with clear rules, robust evidence, and public oversight.
What does Carbon Dioxide Removal (CDR) mean?
Carbon Dioxide Removal refers to the removal of CO₂ from the atmosphere. It refers to processes used to specifically remove carbon dioxide from the air. This can be achieved through technical systems, biological processes, or a combination of both.
CDR is only effective in terms of climate change—in the sense of negative emissions—if the removed CO₂ is stored long-term. If, on the other hand, the CO₂is used, for example in the production of synthetic fuels, it usually ends up back in the atmosphere later on.
Why do we need CO₂ removal at all?
Even with strong climate protection measures, emissions are expected to remain that are difficult or very expensive to avoid. These include, for example, certain emissions from agriculture, industrial processes, waste management, or parts of the transportation sector.
CDR can offset such residual emissions. The central logic is: first avoid emissions as much as possible, then compensate for the truly unavoidable emissions through permanent CO₂ removal. The Intergovernmental Panel on Climate Change (IPCC) emphasizes that CDR is necessary for net-zero targets but is not an alternative to rapid and deep emission reductions.
Does CDR replace emission avoidance?
No. CO₂ removal must not be seen as a free pass to continue emitting large amounts of greenhouse gases. The potential for permanent CO₂removal is limited. Furthermore, various CDR methods are sometimes costly or are not yet available on a large scale. Therefore, emission avoidance remains the most important lever: less fossil fuel use, greater efficiency, electrification, renewable energy, sustainable industrial processes, and more climate-friendly land use.
CDR comes into play where emissions remain despite such measures. The fewer emissions that are avoided beforehand, the larger, more expensive, and riskier the subsequent use of CDR would have to be.
What is the difference between CDR, CCS, and CCU?
CDR refers to the permanent removal of CO₂ from the atmosphere.
CCS means that CO₂ is captured and stored.
CCU means that CO₂ is captured and utilized.
The distinction is important: CCS can be part of CDR if the CO₂ comes from the atmosphere or biogenic sources and is permanently stored. In contrast, if fossil CO₂ from an industrial plant is captured and stored ( ), emissions are avoided, but no negative emissions are generated. With CCU, CO₂ is often used only temporarily. It then re-enters the atmosphere later.
When is CO₂ removal truly effective for the climate?
CO₂ removal is only reliably effective for the climate if four conditions are met:
The CO₂ comes from the atmosphere or from biogenic sources that previously absorbed CO₂.
Storage is guaranteed for the long term and not just for a few years.
The removal is additional, meaning it would not have occurred anyway without the measure.
The entire process chain is accounted for, including energy consumption, transportation, construction, operation, and potential ancillary emissions.
Without these conditions, there is a risk that the actual climate impact will be overestimated.
How much CO₂ can realistically be removed from the atmosphere via CDR?
Today, around 2.1 billion tons of CO₂ are already removed annually worldwide through CDR, almost entirely through traditional land-based methods such as afforestation, reforestation, or improved land management. New technical or more technology-intensive methods—such as DACCS, BECCS, biochar, or accelerated weathering—currently account for only very small amounts. The current contribution of so-called novel CDR methods is only about 1.3 million tons of CO₂ per year. (The State of Carbon Dioxide Removal)
By way of comparison: Global greenhouse gas emissions in 2023 stood at approximately 57.1 billion metric tons of CO₂ equivalents. Today’s CO₂ removal thus amounts to only a few percent of current climate-impacting annual emissions—though the comparison is not perfect, because CDR removes CO₂, while global greenhouse gas emissions also include methane, nitrous oxide, and other gases. (UNEP - UN Environment Programme)
For pathways toward 1.5 degrees, a need for approximately 7 to 9 billion tons of CO₂ removal per year by mid-century is often cited. That would roughly amount to a low double-digit percentage of today’s global greenhouse gas emissions. Realistically, therefore: CDR can make an important contribution in the long term, but it cannot “wipe out” today’s global emissions. The bulk of emissions must be eliminated through emission reductions. (IIASA)
Can we reverse climate change with CDR?
Only to a very limited extent. CDR can help reduce CO₂ concentrations in the atmosphere over the long term or partially reverse a temperature increase. However, it cannot simply reverse many climate impacts.
Lost ecosystems, species extinction, damage from extreme weather, or melted ice sheets cannot be repaired at will. Furthermore, there are tipping points in the Earth system; exceeding them could potentially result in irreversible climate changes. Therefore, CDR is not a Plan B for later, but a complement to immediate emissions reductions.
Are natural solutions like forests and wetlands better than technical methods?
Not necessarily. Natural solutions can have many advantages: they promote biodiversity, improve water balance and soil quality, and are often well-received by the public. Their weakness lies in the uncertainty of storage. Wildfires, drought, pest infestations, or subsequent changes in land use can release stored carbon back into the atmosphere.
Technical methods can often store CO₂ more permanently and are easier to scale up globally, but they are usually more expensive, more energy-intensive, and more demanding in terms of infrastructure. Therefore, an “either-or” approach makes no sense; instead, a clear assessment based on permanence, costs, risks, land requirements, and additional benefits is needed.
What are the risks associated with negative emission technologies?
The risks vary depending on the method. Common points of contention include:
high energy requirements, especially for direct air capture,
competition for land, biomass, or water,
impacts on biodiversity and food security,
unclear long-term responsibility for CO₂ storage,
high costs,
acceptance issues regarding infrastructure and storage sites,
uncertain evidence of actual CO₂ removal.
These risks do not mean that CDR is fundamentally problematic. However, they do show that processes must be carefully evaluated, regulated, and communicated transparently.
Why does CDR need a CO₂ infrastructure?
Many CDR processes do not remove CO₂ where it can later be stored or utilized. Therefore, transport routes and storage facilities are needed. These include pipelines, ships, rail or truck transport, as well as suitable geological storage sites.
This infrastructure must be planned early on. If Germany only takes CO₂ removal into account once facilities are already slated for construction, bottlenecks are likely to arise. The policy paper therefore emphasizes that future CO₂ volumes from negative emissions should be incorporated into infrastructure planning from the very beginning.
Why is CDR a topic for energy research?
Many CDR processes are closely linked to the energy system. Direct air capture plants require large amounts of renewable energy. BECCS is linked to biomass, electricity, and heat generation. CO₂ transport and storage must be considered in conjunction with industry, waste management, and infrastructure planning.
The crucial question is therefore not just: “Which technology can remove CO₂?” but rather: “How does this technology fit into a climate-neutral energy and industrial system without creating new conflicts of interest?”
How can we prevent CDR from becoming greenwashing?
This requires clear rules. Every CO₂ removal credited must be measurable, verifiable, additional, and as permanent as possible. Furthermore, we must prevent the same removal from being counted multiple times—for example, by a company and simultaneously by a government.
It is also important to distinguish between emissions avoidance and CO₂ removal. Those who reduce fossil fuel emissions prevent harm. Those who remove CO₂ offset harm. Both are important, but they are not the same.
What role does Germany play in CDR?
Germany is increasingly discussing CDR in the context of climate neutrality and unavoidable residual emissions. However, concrete rules for funding, crediting, infrastructure, and market ramp-up have not yet been fully developed.
Other European countries are already further along in certain areas. Denmark and Sweden, for example, have established funding instruments for biogenic CO₂ capture and storage. Germany can learn from such experiences but must develop its own solutions for energy supply, industry, land use, storage issues, and societal acceptance.
What does research need to clarify now?
Research must primarily answer three questions:
First: Which CDR processes are truly sustainable, durable, and scalable?
Second: How can these processes be meaningfully integrated into energy, industrial, and infrastructure systems?
Third: Which policy rules and incentives lead to genuine CO₂ removal rather than false solutions?
This requires technical research, energy system analysis, environmental assessment, economic analysis, and public participation. It is precisely this integrated approach that the policy paper calls for.
