RETAKE Synergy Summit 2025
At the RETAKE Synergy Summit 2025 – held on March 6, 2025 – experts from the CDRmare research consortium RETAKE, which investigates CO₂ removal through enhanced rock weathering / ocean alkalinization, met at GEOMAR in Kiel with stakeholders from industry, academia, political representatives, and local authorities from Kiel and Schleswig-Holstein. The event was part of the knowledge transfer within the RETAKE research consortium and aimed to connect researchers with industry and regional decision-makers to develop ideas for responsibly designed pilot projects in coastal areas.
So far, research on the potential, benefits, and risks of enhanced rock weathering / ocean alkalinization within RETAKE has been conducted exclusively under controlled, enclosed conditions complemented by computer-based models. This includes laboratory experiments, benthocosm studies (sediment), and mesocosm studies (water column). However, the applicability of these research findings to complex marine habitats, where ocean currents continuously exchange water, is currently limited. To bridge this gap, small-scale coastal pilot projects are needed.
The state of Schleswig-Holstein and the city of Kiel have set the goal of achieving CO₂ neutrality. This can only be accomplished through a massive reduction of CO₂ emissions. However, hard-to-avoid residual CO₂ emissions must be offset through carbon removal methods that capture CO₂ from the atmosphere. Thus, enhanced rock weathering / ocean alkalinization could potentially contribute to CO₂ neutrality in Schleswig-Holstein in the future.
Given the significant potential for CO₂ removal from the atmosphere, further research on enhanced rock weathering / ocean alkalinization is essential. It offers the opportunity to provide concrete scientific answers to the pressing question: How can hard-to-avoid residual CO₂ emissions be responsibly and permanently removed from the atmosphere without endangering marine ecosystems? This urgent need for research aligns with a clear political objective – CO₂ neutrality – which can only be achieved through massive emission reductions as well as innovative and environmentally sustainable solutions.
At the RETAKE Synergy Summit at GEOMAR in Kiel, ideas and concepts for potential regional pilot projects on enhanced rock weathering / ocean alkalinization were developed and discussed. Additionally, the requirements for potential implementations were examined. Alongside the technical and administrative challenges, a particular focus was placed on the important question of how, in the case of a planned project, the population and all relevant authorities and committees could be involved in the planning and implementation from the very beginning.
The event was conducted in German. The agenda and expert presentations are available for download (German only).
The workshop was organized by the CDRmare research consortium RETAKE in cooperation with the Kiel Science Center.
Participating Institutions
A total of 49 participants from the following 35 institutions attended the event:
BioConsult GmbH & Co. KG
Bundeswehr
Carbon to Sea Initiative
Deutsche Energie-Agentur GmbH
Dezernat Umwelt, Klimaschutz und Mobilität der Stadt Kiel
Christian-Albrechts-Universität zu Kiel
Christian-Albrechts-Universität zu Kiel | Kiel Marine Science
Fachhochschule Kiel
Fels-Werke GmbH
Forschungsgemeinschaft Kalk und Mörtel e.V.
Forschungsmission CDRmare
Forschungsprojekt CDRatlas
Forschungsverbund ASMASYS
Forschungsverbund OCEAN ALK-ALIGN
Forschungsverbund RETAKE
Generaldirektion Wasserstraßen und Schifffahrt
GEOMAR | Forschungsförderung und Transfer
GEOMAR | Technologietransfer
Gesellschaft für Energie und Klimaschutz Schleswig-Holstein GmbH
Industrie‑ und Handelskammer Schleswig-Holstein
Kieler Wirtschaftsförderungs- und Strukturentwicklungs GmbH
Klärwerk Bülk
Landeskriminalamt – Kampfmittelräumdienst
Leibniz-Institut für Ostseeforschung Warnemünde
Maritimes Cluster Norddeutschland e. V.
Ministerium für Energiewende, Klimaschutz, Umwelt und Natur Schleswig-Holstein
Müllverbrennung Kiel GmbH & Co. KG
Planeteers GmbH
Stadt Kiel
Stadtwerke Kiel AG
thyssenkrupp Marine Systems GmbH
TransMarTech Schleswig-Holstein GmbH
Wasserstraßen- und Schifffahrtsamt Ostsee
Wissenschaftszentrum Kiel
Zeiten°Grad Krug und Poggemann eGbR
Downloads
As the event was conducted in German, the agenda and expert presentations are available for download in German only.
Moderation
Dr. Tim Boxhammer | GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel
Kristin Hamann | GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel
Daniel Laufs | Wissenschaftszentrum Kiel
Klimaschutzziele des Landes Schleswig-Holstein
Dr. Anna-Catharina Wollmer | Ministerium für Energiewende, Klimaschutz, Umwelt und Natur SH
Klimaschutzziele der Landeshauptstadt Kiel
Dr. Maria Hock | Dezernat für Umwelt, Klimaschutz und Mobilität der Stadt Kiel
Beschleunigte Gesteinsverwitterung / Alkalinisierung
Status Quo der Forschung und Chancen für das Erreichen von Klimaneutralität
Prof. Dr. Andreas Oschlies | GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel
Rechtliche Rahmenbedingungen für Alkalinisierung
Aktuelle Gesetzeslage und anstehende Gesetzesänderungen für Forschungsvorhaben
Nicole Herold | Deutsche Energie-Agentur GmbH
Pilot-Option I: Beschleunigte Gesteinsverwitterung in Reaktoren
Frank Rattey | PLANETEERS GmbH
Pilot-Option II: Künstliche Kalkstein-3D-Strukturen im Meer
Prof. Dr. Andreas Oschlies | GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel
Photos: Daniel Laufs, Wissenschaftszentrum Kiel