CO₂-removal News

Peer-reviewed Publications

Rathnayake et al. (2024): Quantifying soil organic carbon after biochar application: how to avoid (the risk of) counting CDR twice?

Dilani Rathnayake, Hans-Peter Schmidt, Jens Leifeld, Diane Bürge, Thomas D. Bucheli, Nikolas Hagemann IN: Frontiers in Climate, https://doi.org/10.3389/fclim.2024.1343516

The objectives of this review are (1) to compare the physicochemical properties and the quantities of biochar and SOC fractions on a global and field/site-specific scale, (2) to evaluate the established methods of SOC and pyrogenic carbon (PyC) quantification with regard to their suitability in routine analysis, and (3) to assess whether double counting of SOC and biochar C-sinks can be avoided via analytical techniques.

LINK

#
Peer-reviewed Publications

Næss et al. (2024): Bridging Quantitative and Qualitative Science for BECCS in Abandoned Croplands

Jan Sandstad Næss, Ida Marie Henriksen, Tomas Moe Skjølsvold IN: Earth’s Future 12 (3), e2023EF003849, https://doi.org/10.1029/2023EF003849

Bioenergy with carbon capture and storage plays a vital role in most climate change mitigation scenarios, where a solution for sustainable near-term bioenergy expansion is to grow energy crops such as perennial grasses on recently abandoned cropland. This study combines natural science insights anchored in quantitative bioenergy modeling with qualitative social science anchored in the multi-level perspective. Using these mixed methods enables a global-to-local-to-global level assessment of near-term bioenergy recultivation opportunities for abandoned cropland. Norway is the local case. 

LINK

#
Peer-reviewed Publications

Wu et al. (2024): Operating optimization of biomass direct-fired power plant integrated with carbon capture system considering the life cycle economic and CO2 reduction performance

Xiao Wu, Ziteng Zhang, Xuan Zhang IN: Renewable Energy 225, 120294, https://doi.org/10.1016/j.renene.2024.120294

Biomass direct-fired power plant integrated with carbon capture system can achieve negative CO2 emission during the power generation, which provides an important technology pathway for the transformation of energy system towards carbon neutrality. Understanding the economic competitiveness and CO2 reduction potential of the plant, and identifying the optimal operating mode are the key to fully exert the advantages of the technology. For this reason, this paper develops life cycle economic and CO2 emission assessment models for the biomass direct-fired circulating fluidized bed boiler power plant integrated with solvent-based post-combustion carbon capture system. 

LINK

#
Peer-reviewed Publications

Xu et al. (2024): Durability and micromechanical properties of biochar in biochar-cement composites under marine environment

Weijian Xu, Yuying Zhang, Muduo Li, Fulin Qu, Chi Sun Poon, Xiaohong Zhu, Daniel C.W. Tsang IN: Journal of Cleaner Production 450, 141842, https://doi.org/10.1016/j.jclepro.2024.141842

Integrating biochar into traditional construction materials presents a promising avenue to reduce carbon emissions from the construction industry. While recent research has focused on the performance of biochar-cement materials, limited attention is given to the durability of biochar in cementitious materials. This study investigated the alterations in the structural, chemical, and mechanical properties of biochar in the cementitious system and marine environment. 

LINK

#
Peer-reviewed Publications

Block et al. (2024): Analysing direct air capture for enabling negative emissions in Germany: an assessment of the resource requirements and costs of a potential rollout in 2045

Simon Block, Peter Viebahn, Christian Jungbluth IN: Frontiers in Climate 6, https://doi.org/10.3389/fclim.2024.1353939

The aim of this paper is to analyse and comparatively classify the resource consumption (land use, renewable energy and water) and costs of possible DAC implementation pathways for Germany. The paths are based on a selected, existing climate neutrality scenario that requires the removal of 20 Mt of CO2 per year by DACCS from 2045. The analysis focuses on the so-called “low-temperature” DAC process, which might be more advantageous for Germany than the “high-temperature” one.

LINK

#
Peer-reviewed Publications

Nature – Macintosh et al. (2024): Australian human-induced native forest regeneration carbon offset projects have limited impact on changes in woody vegetation cover and carbon removals

Andrew Macintosh, Don Butler, Pablo Larraondo, Megan C. Evans, Dean Ansell, Marie Waschka, Rod Fensham, David Eldridge, David Lindenmayer, Philip Gibbons, Paul Summerfield IN: Communications Earth & Environment, https://doi.org/10.1038/s43247-024-01313-x

The authors analysed the performance of one of the world’s largest nature-based offset types: human-induced regeneration projects under Australia’s carbon offset scheme. The projects are supposed to involve the human-induced regeneration of permanent even-aged native forests through changes in land management. They analysed 182 projects and found limited evidence of regeneration in credited areas. Changes in woody vegetation cover within the areas that have been credited also largely mirror changes in adjacent comparison areas, outside the projects, suggesting the observable changes are predominantly attributable to factors other than the project activities. 

LINK

#
Peer-reviewed Publications

Nature – Mathis et al. (2024): Enhanced CO2 uptake of the coastal ocean is dominated by biological carbon fixation

Moritz Mathis, Fabrice Lacroix, Stefan Hagemann, David Marcolino Nielsen, Tatiana Ilyina, Corinna Schrum IN: Nature Climate Change, https://doi.org/10.1038/s41558-024-01956-w

Observational reconstructions indicate a contemporary increase in coastal ocean CO2 uptake. However, the mechanisms and their relative importance in driving this globally intensifying absorption remain unclear. Here the authors integrate coastal carbon dynamics in a global model via regional grid refinement and enhanced process representation.

LINK

#
Media

Exploring Durability Curves — An Enhanced Lens for Evaluating Carbon Removals

by Rick Berg, Radhika Moolgavkar, Nori, March 26, 2024

„The durability of sequestered carbon, and credits designed to represent it, has gotten a lot of focus in discussions around the voluntary carbon dioxide removal (CDR) markets and emerging mandatory carbon markets. This attention is well-deserved. Durability characteristics play a key role in the functioning of the markets, including how the carbon removal credits are used, the development of carbon insurance, the management of carbon credit portfolio risks, and the creation of credit ratings. „

LINK

#
Peer-reviewed Publications

Nature – Hasler et al. (2024): Accounting for albedo change to identify climate-positive tree cover restoration

Natalia Hasler, Christopher A. Williams, Vanessa Carrasco Denney, Peter W. Ellis, Surendra Shrestha, Drew E. Terasaki Hart, Nicholas H. Wolff, Samantha Yeo, Thomas W. Crowther, Leland K. Werden & Susan C. Cook-Patton IN: Nature Communications, 15, https://doi.org/10.1038/s41467-024-46577-1

Restoring tree cover changes albedo, which is the fraction of sunlight reflected from the Earth’s surface. In most locations, these changes in albedo offset or even negate the carbon removal benefits with the latter leading to global warming. Previous efforts to quantify the global climate mitigation benefit of restoring tree cover have not accounted robustly for albedo given a lack of spatially explicit data. Here the authors produce maps that show that carbon-only estimates may be up to 81% too high.

LINK

#