CO2-removal News

Peer-reviewed Publications

Shehzad et al. (2025): Dynamic modeling and optimal control schemes for an offshore-wind powered direct air capture system with energy storage options

Muhammad Faisal Shehzad, Haris Ishaq, Curran Crawfrod, IN: Science of The Total Environment, https://doi.org/10.1016/j.scitotenv.2025.179537

This paper proposes an offshore-wind energy powered atmospheric CO₂ capture system. A key challenge is the variable nature of renewable wind-energy to meet direct air capture (DAC) system power requirements. One solution to mitigate this challenge is to integrate the wind-CO₂ capture system with advanced Energy Storage Systems (ESS). Previous research in this direction has been carried out, however the optimal ESS is still an open question due to the limitations and constraints of each ESS technology. The constraints include concerns over degradation, ESS response times, and overall costs. This paper proposes an advanced energy management strategy (EMS) within the CO₂ capture system to address the outlined problems. It presents a dynamic model for offshore-wind direct air capture of CO₂ system coupled with a battery-based energy storage system with the objective of maximizing CO₂ removal from air while fulfilling the overall system operational constraints and dynamics. More specifically, the proposed model investigates the flexibility of the CO₂ capture system with respect to wind power supply in different seasons. The DAC models proposed in this research consists of a three state automaton, namely: OFF, Adsorption, and Desorption which handle the three operational states of the proposed CO₂ capture system. In order to maximally utilize wind power availability, each operational state of the proposed model is considered as a separate load and dispatched separately. The proposed approach is then compared and analyzed by scheduling the system as a whole. Numerical results illustrate the feasibility of powering CO₂ capture system via variable wind power.

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Peer-reviewed Publications

Nature – Hassan et al. (2025): A Membraneless Electrochemically Mediated Amine Regeneration for Carbon Capture

Ahmad Hassan, Mohsen Afshari & Mim Rahimi, IN: Nature Communications, https://doi.org/10.1038/s41467-025-61525-3

Among electrochemical carbon captures (ECCs), electrochemically mediated amine regeneration (EMAR) reached higher technology readiness levels, moving from small-scale laboratory studies toward pilot-scale implementations. Previous EMAR systems rely on ion-selective membranes, which contribute significantly to the cost and present challenges for long-term operation. This study presents a membraneless EMAR system by fundamentally redesigning the process configuration and using gas diffusion electrodes (GDEs) as both the anode and cathode. This setup eliminates the membrane and the need for additional equipment such as the absorption column, flash tank, and pumps, significantly reducing the process footprint and simplifying the flow diagram. Two GDE configurations, mesh-attached and electrodeposited, are tested and compared in terms of CO₂ removal efficiency, current density, and energy consumption.

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Peer-reviewed Publications

Saharudin et al. (2025): Building with biomass using tropical timber as a negative emissions technology (NET): Sustainability assessment, comparison with other bio-based NETs and their potential in Malaysia

Djasmine Mastisya Saharudin, Harish Kumar Jeswani, Adisa Azapagic, IN: Sustainable Production and Consumption, https://doi.org/10.1016/j.spc.2025.06.017

This paper is the first to determine the environmental impacts and economic feasibility of building with biomass using timber, focusing on the residential housing sector in a developing country such as Malaysia. Four tropical hardwood species are considered: resak, keruing, sesenduk and rubber. The environmental assessment comprises 18 life cycle assessment impacts and the economic assessment focuses on life cycle costs. The system boundary includes all activities from cradle to grave, i.e. from timber production to house demolition.

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Peer-reviewed Publications

Nature – O’Sullivan et al. (2025): Who pays for carbon dioxide removal? Public perceptions of risk and fairness of enhanced rock weathering in the UK

Kate O’Sullivan, Nick Pidgeon, Karen Henwood, Fiona Shirani & Harriet Smith, IN: Humanities and Social Sciences Communications, https://doi.org/10.1057/s41599-025-05384-9

With undefined social and environmental costs, and evolving economic and governance systems, enhanced rock weathering (ERW) raises issues for public acceptance. A literature gap exists regarding how local communities view the possibility of at-scale deployment in their area. The authors address this with data from five UK public workshops to identify conditions under which communities potentially impacted by ERW consider deployment fair and acceptable. The authors show that public acceptance is conditional upon place-sensitive deployment pathways that reflect how place is valued. Analysis highlights opportunities to minimise risk and maximise benefits experienced locally; the importance of transparent governance and monitoring; and unbiased, balanced communication of impacts.

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Peer-reviewed Publications

Rustogi et al. (2025): Influence of Wave-Induced Variability on Ocean Carbon Uptake

P. Rustogi, L. Resplandy, E. Liao, B. G. Reichl, L. Deike, IN: Global Biogeochemical Cycles, https://doi.org/10.1029/2024GB008382

High-frequency wind and wave variability influence air-sea gas fluxes by modulating the gas transfer velocity at the interface. Traditional gas transfer velocity formulations scale solely with wind speed and neglect wave effects, including wave breaking and bubble-mediated transfer. In this study, the authors quantify the influence of wave effects on the air-sea CO₂ flux and ocean carbon storage using a wind-wave-bubble gas transfer velocity formulation in an ocean general circulation model (MOM6-COBALTv2).

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Peer-reviewed Publications

Miao et al. (2025): Biochar-zeolite modified super sulphate cement as a high-performance, sustainable and high-efficiency CO₂ sequestration cementitious material

Jianxiong Miao, Shuai Xiao, Yang Zhou, Wentao Chen, Yanji Jin, Luqing Cheng, Cheng Chang, Hao Zhang, IN: Construction and Building Materials, https://doi.org/10.1016/j.conbuildmat.2025.142475

Cement production contributes 8 % of global industrial carbon emissions, underscoring the urgent need for innovative strategies to mitigate its environmental impact. Super Sulfated Cement (SSC) is a promising low-carbon alternative, but its carbon sequestration potential remains underexplored. This study integrates biochar and zeolite into SSC to create a near-zero-carbon, high-performance composite with hierarchical transport pathways, enhancing compressive and flexural strength by 63.1 % and 43.8 %. A comprehensive mechanism for the composite’s carbon sequestration is proposed, leveraging biochar’s tunnel-like channels and zeolite’s nano-pores, along with molecular sieve properties, to create a hierarchical pore structure.

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Peer-reviewed Publications

Nature – Guo et al. (2025): Site selection for ocean alkalinity enhancement informed by passive tracer simulations

Yiming Guo, Ke Chen, Adam V. Subhas, Jennie E. Rheuban, Zhaohui Aleck Wang, Daniel C. McCorkle, Anna Michel & Heather H. Kim, IN: Communications Earth & Environment, https://doi.org/10.1038/s43247-025-02480-1

The physical circulation of ocean water exerts fundamental control on the dilution, spreading, and retention of alkaline materials, influencing carbon removal effectiveness, environmental impacts, and monitoring feasibility. Here the authors evaluate potential sites and timing for ocean alkalinity enhancement on the U.S. Northeast Shelf by conducting passive tracer simulations from 2009 to 2017. Monthly dye release experiments across ten locations were analyzed by quantifying dye evolution metrics such as surface spread, lateral movement, upper-ocean concentration, and gas transfer velocity. A site selection index was developed to assess site and time suitability for tracer dispersal for ocean alkalinity enhancement.

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Peer-reviewed Publications

Soterroni et al. (2025): Assessing Potential Implications of the EU’s Carbon Dioxide Removal Strategy on Brazil’s Land Ecosystems and Local Communities

Soterroni, Antonella Mazzone, Jiesper Tristan, IN: Environmental Science & Policy, https://doi.org/10.1016/j.envsci.2025.104154

The European Union (EU)’s commitment to achieving climate neutrality by 2050 relies significantly on Carbon Dioxide Removal (CDR) strategies, yet implications of such approaches for the Global South remain unclear. Here the authors reflect on how land-based CDR ambitions in the EU—particularly BECCS—may generate disproportionate pressures on ecosystems and communities in countries like Brazil, which have become a focal point for climate mitigation due to their biophysical potential and geopolitical ties. Although Brazil is not formally committed to providing land-based offsets to the EU, its significant potential to host large-scale afforestation and BECCS projects renders it a useful case study for exploring these dynamics.

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Peer-reviewed Publications

Pisciotta et al. (2025): Advancing Geothermal Energy Utilization Opportunities: Potential and Strategies for Integrating Direct Air Capture

Maxwell Pisciotta, Hélène Pilorgéa, Likhwa Ndlovua, Madeleine Siegelb, Joe Huyettb, Todd Bandhauerb, Peter Psarrasa and Jennifer Wilcox, IN: Energy & Environmental Science, https://pubs.rsc.org/en/content/articlehtml/2025/ee/d4ee04058a

This study explores the potential of geothermal resources to meet the thermal and electrical demands of DAC systems through the development of a geothermal-DAC evaluation framework. The framework examines configurations where binary geothermal power plants and DAC units are engineered to optimize geothermal resource use. These configurations are evaluated based on their CO₂ abatement potential, achieved by displacing carbon-intensive grid electricity and removing atmospheric CO₂. The framework was applied to two hypothetical geothermal resources, representing low (86 °C) and high (225 °C) temperature regimes for binary geothermal power plants, considering various organic Rankine cycle (ORC) working fluids. It was also tested on the Raft River binary geothermal combined cycle power plant.

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Peer-reviewed Publications

Ozden et al. (2025): Point-Source Carbon Capture and Direct Air Capture – A Technology Overview

Adnan Ozden, Mingchuan Luo, Yanwei Lum, IN: Chemical Engineering Journal, https://doi.org/10.1016/j.cej.2025.165535

This review provides an overview of today’s two most studied CO₂ capture and removal technologies: point-source CO₂ capture and direct air capture. It presents recent advances associated with each technology, highlights the advantages, challenges and remaining milestones, and discusses the potential research directions for feasibility enhancements.

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