Publications

Geological carbon dioxide removal (CDR), which stores carbon permanently, is necessary to reach durable net zero. However, CDR faces numerous challenges in scaling up, including demand creation, supply promotion, and a need for better regulatory frameworks. This policy brief assesses the most commonly considered policies to support geological CDR, including integration into an emissions trading scheme, tax breaks, voluntary carbon markets, extended producer responsibility, public procurement schemes, advanced market commitments, direct grants, and carbon contracts for difference. The authors examine how each of these instruments performs against the key criteria of effectiveness, efficiency, feasibility, and strategic fit, drawing on established economic principles and emerging best practices.

The authors assess the most commonly discussed policies for geological carbon dioxide removal, using a set of criteria for policy evaluation (Stringency, Efficiency, Feasibility and Strategic Fit, with a range of sub-questions). They also evaluate policy combinations and interactions, with a particular focus on containing government expenditure and ensuring that policy combinations support technology development at different technology readiness levels.

In January 2025, representatives from the Department for Energy Security and Net Zero (DESNZ), CO2RE and the Industrial Decarbonisation Research and Innovation Centre (IDRIC) held a workshop on carbon capture, utilisation and storage (CCUS) and engineered greenhouse gas removal (eGGR) technologies. The aims of the workshop were to support DESNZ in identifying the existing technical evidence and pinpoint the gaps for the deployment of CCUS and eGGRs; engage with interested and active organisations in sharing the current barriers and challenges to the deployment of CCUS and eGGRs; understand what technical evidence needs to be gathered to resolve barriers and challenges for CCUS/eGGRs and how; and facilitate knowledge exchange with subject matter specialists. This document describes the discussions that took place and the insights that were shared.

When upscaling novel techniques for Carbon Dioxide Removal (CDR), public attitudes are crucial, yet there is a serious lack of social science research outside of Western nations. CDR research can clearly benefit from maximising inclusion and opening up to diverse perspectives, including those of local communities, and ideally should involve public insight into the questions we should be prioritising. This paper reports results from a major deliberative study on public perceptions of CDR in Malaysia. We demonstrate a novel, transferrable methodology called “Question-Led Innovation”, in which lay public and local stakeholders are empowered to ask actionable questions on a novel intervention or innovation. These questions are then used as the basis for identifying priorities for future scientific research. We apply the methodology to a case study of CDR via Enhanced Rock Weathering (ERW) on tropical palm oil agriculture in Sabah.

Scaling up CO2 removal is crucial to achieve net-zero targets and limit global warming. To engage with publics and ensure a social licence to deploy large-scale carbon dioxide removal (CDR), better understanding of public perceptions of these technologies is necessary. Here, we analyse attention and sentiments towards ten CDR methods using Twitter data from 2010 to 2022. Attention towards CDR has grown exponentially, particularly in recent years. Overall, the discourse on CDR has become more positive, except for BECCS. Conventional CDR methods are the most discussed and receive more positive sentiments. Various types of users engage with CDR on Twitter to different degrees: While users posting little about CDR pay more attention to methods with biological sinks, frequently engaged users focus more on novel CDR methods. Our results complement survey studies by showing how awareness grows and perceptions change over time.

Soil health is a critical component of nature-based solutions (NbS), underpinning ecosystem multifunctionality and resilience by supporting biodiversity, improving carbon sequestration and storage, regulating water flow and enhancing plant productivity. For this reason, NbS often aim to protect soil health and restore degraded soil. Robust monitoring of soil health is needed to adaptively manage NbS projects, identify best practices and minimize trade-offs between goals, but soil assessment is often underrepresented in NbS monitoring programmes. This paper examines challenges and opportunities in selecting suitable soil health metrics.

The energy modelling community’s analysis of net zero often relies on approaches that hide the extent of uncertainty. Meanwhile the extent of uncertainty involved in the realisation of net zero is proliferating. Conventional consolidative modelling approaches lack of transparency is distorting decision making and policy design around net zero. This contribution uses the UK’s Committee on Climate Changes 6th Carbon Budget as a case study. An exploratory, Robust Decision-Making approach is used to highlight the fragility of conventional UK modelling approaches in shaping national climate policy. A new suite of tools, orientation of analysis and mixed approaches are needed to address the extent of complexity, uncertainty and emergence in possible net zero futures. Only then will robust, inclusive and realisable climate policy be designed.

Carbon dioxide removal (CDR) involves capturing CO2 from the atmosphere and storing it for decades to millennia. Alongside deep emissions reductions, CDR is required for meeting the temperature goal of the Paris Agreement (IPCC 2022). However, parties to the agreement do not currently distinguish CDR from emissions reductions in their climate pledges. In this perspective, we argue that this lowers transparency and hinders the assessment of how credible and ambitious mitigation plans are.

In November 2024, Professor Colin Snape, who leads the Biochar Demonstrator project, and Dr Steve Smith, Executive Director of CO2RE, wrote to the Secretary of State for Environment, Food and Rural Affairs and the Secretary of State for Energy Security and Net Zero to highlight the regulatory and policy gaps that hinder the development of the biochar and other land-based GGR sectors. Their letter recommends changes to waste regulation, carbon valuation and policy ownership within government, with oversight from a cross-departmental task force, to set a holistic framework for biochar in the UK.

Achieving net zero global emissions of carbon dioxide (CO2), with declining emissions of other greenhouse gases, is widely expected to halt global warming. CO2 emissions will continue to drive warming until fully balanced by active anthropogenic CO2 removals. For practical reasons, however, many greenhouse gas accounting systems allow some “passive” CO2 uptake, such as enhanced vegetation growth due to CO2 fertilisation, to be included as removals in the definition of net anthropogenic emissions. By including passive CO2 uptake, nominal net zero emissions would not halt global warming, undermining the Paris Agreement. Here we discuss measures addressing this problem, to ensure residual fossil fuel use does not cause further global warming: land management categories should be disaggregated in emissions reporting and targets to better separate the role of passive CO2 uptake; where possible, claimed removals should be additional to passive uptake; and targets should acknowledge the need for Geological Net Zero, meaning one tonne of CO2 permanently restored to the solid Earth for every tonne still generated from fossil sources. We also argue that scientific understanding of net zero provides a basis for allocating responsibility for the protection of passive carbon sinks during and after the transition to Geological Net Zero.