Carbon dioxide removal as a building block of German climate policy
In order to achieve the Paris climate targets, greenhouse gas emissions must be massively reduced. In addition, CO2 that has already been emitted must be removed from the atmosphere. Scientists at the Helmholtz Center for Environmental Research - UFZ have set out definitions and principles for CO2 removal in a paper.
According to the latest Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), reducing carbon dioxide (CO2) emissions is not enough to achieve the goals of the Paris Climate Agreement. In addition, CO2 that has already been emitted must be removed from the atmosphere.
Approaches to CO2 removal include the enhancement of natural carbon sinks, for example through the reforestation or the rewetting of peatlands, technical measures or rather negative emission technologies (NETs), or a combination of both approaches.
Several studies show that technology-based processes such as the capture of CO2 from industrial waste gases with subsequent underground storage (Carbon Dioxide Capture and Storage, CCS) or the direct removal of CO2 from the ambient air (Direct Air Capture) will be required both globally and in Germany. To this end, various approaches must be thoroughly evaluated and researched. International and national climate legislation must be developed accordingly. We have set out our proposals in this respect in a recent paper (in German).
Supplementary measure to avoiding greenhouse gases
It is important to make a clear political and legal distinction between measures to avoid CO2 and measures to remove CO2. The former prevent climate-damaging greenhouse gases from being produced, while the latter merely make CO2 that has already been produced ineffective for the climate through use of energy, technology or interventions in the environment. Against this background, greenhouse gases should be avoided in the first place and CO2 removal should only be considered as a complementary measure.
According to the IPCC report from 2022, CO2 removal is "unavoidable" in order to offset the so-called "hard-to-abate residual emissions". These include emissions from the steel and cement industries, among others. The approaches that build up natural sinks should not be played off against technical processes, but should be combined in such a way that the advantages and disadvantages are balanced in the best possible way.
Government support, climate legislation and incentives
As with other innovations, government support is crucial in order to accelerate the development of technologies for carbon capture, removal, transportation and storage. By promoting research and development, the often still high costs can be reduced and the safety of the technologies improved. Due to the urgency, the focus should be on promising solutions such as CO2 capture from large biomethane, bioethanol and waste incineration plants or on biochar, for example from sewage treatment plants.
Staatliche Unterstützung, Klimarecht und Anreize
Wie bei anderen Innovationen ist die staatliche Unterstützung für die beschleunigte Entwicklung von Technologien zur CO2-Abscheidung, -Entnahme, -Transport und -Speicherung entscheidend. Durch die Förderung von Forschung und Entwicklung können die oftmals noch hohen Kosten verringert und die Sicherheit der Technologien verbessert werden. Aufgrund der Dringlichkeit sollte dabei der Fokus auf vielversprechende Lösungen wie die CO2-Abscheidung aus großen Biomethan-, Bioethanol- und Abfallverbrennungsanlagen oder auch auf Pflanzenkohle, zum Beispiel aus Kläranlagen, gelegt werden.
In order to adequately control the capture, extraction and storage of CO2, existing international and national climate legislation must also be further developed. The legislation must enable the development of appropriate infrastructures and remove legal barriers to international cooperation on carbon dioxide storage. This includes legal certainty for CO2 transportation networks, crediting criteria, monitoring systems, environmental standards and liability regulations.
Mandatory and voluntary carbon trade and the commercial utilization of the removed CO2 can provide additional incentives for CO2 removal. The market potential for carbon offsetting in particular appears to be considerable. In order to integrate CO2 removal into these markets, a regulatory and institutional framework must be developed that enables the credibility of the information on carbon dioxide removal and storage.
Die Helmholtz-Expert:innen
Daniela Thrän ist Professorin für Bioenergiesysteme an der Universität Leipzig und leitet das Department Bioenergie am Helmholtz-Zentrum für Umweltforschung – UFZ. Sie befasst sich mit der Analyse und Bewertung von biobasierten negativen Emissionen in net zero Energiesystemen und nachhaltiger Bioökonomie wie z.B. dem BioNET-Projekt.
Till Markus ist Jurist und arbeitet als Wissenschaftler am Helmholtz-Zentrum für Umweltforschung - UFZ. Dort befasst er sich aktuell mit den rechtlichen Fragen des Klimaschutzes und der Energiewende. Er ist beteiligt an Projekten wie DACStorE, GONASIP und Zukunftsfähiges Umweltrecht im Anthropozän.
Danny Otto ist Soziologe. Als Wissenschaftler am Helmholtz-Zentrum für Umweltforschung - UFZ befasst er sich unter anderem mit Fragen der gesellschaftlichen Wahrnehmung und Bewertung von negativen Emissionstechnologien bzw. Technologien zu CO2-Speicherung - aktuell etwa in den Projekten BioNET und RamonCO.
Expertise
