Imperial College London


Faculty of EngineeringDepartment of Chemical Engineering

Research Postgraduate



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C504Roderic Hill BuildingSouth Kensington Campus





PhD Title: "A critique of the representation of carbon capture and storage (CCS) and carbon dioxide removal (CDR) in integrated assessment models."

Supervisors: Dr Ajay Gambhir and Dr Adam Hawkes

I am a PhD candidate based at the Grantham Institute for Climate Change and the Environment, and am part of the 5th cohort of the 'Science and Solutions for a Changing Planet' (SSCP) Doctoral Training Partnership, funded by NERC. My research focuses on the representation of CCS and CDR in integrated assessment models (IAMs), criticising and improving this representation.

Tackling climate change will require a rapid transition to a net-zero economy. There remains considerable uncertainty about the best path by which to achieve this transformational goal. IAMs have been used to explore the diversity of mitigation pathways and provide evidence on their relative strengths and weaknesses.

A consistent message from IAM modelling has been the value of large-scale CCS and CDR deployment. IAMs have represented these interrelated technologies as critical to least-cost decarbonisation. At the same time, low-carbon scenarios produced by IAMs have been heavily criticised, in part due to their reliance on CCS and CDR. There is a nexus between widespread scepticism about CCS and CDR, and scepticism about the models which foreground them as key solutions.

This thesis situates itself in this nexus. It conducts a model-based investigation and critique of the representation of CCS and CDR in integrated assessment models. Using a detailed-process IAM, it explores how the pre-dominant representation of CCS and CDR can be challenged, and therefore how the narrative that IAMs provide about CCS/CDR can be altered.

I am interested in working in UK climate policy, and as part of my PhD have worked closely with the Climate Change Committee (CCC) on the Net Zero and Sixth Carbon Budget reports, WWF on an ambitious and feasible NDC for the UK, and the All-Party Parliamentary Climate Change Group (APPCCG) on tracking UK climate policy development in the run-up to COP26. 

Selected Publications

Journal Articles

Grant N, 2022, The Paris Agreement’s ratcheting mechanism needs strengthening 4-fold to keep 1.5°C alive, Joule, Vol:6, ISSN:2542-4351, Pages:703-708

Grant N, Hawkes A, Napp T, et al., 2021, Cost reductions in renewables can substantially erode the value of carbon capture and storage in mitigation pathways, One Earth, Vol:4, ISSN:2590-3322, Pages:1588-1601

Grant N, Hawkes A, Mittal S, et al., 2021, The policy implications of an uncertain carbon dioxide removal potential, Joule, Vol:5, ISSN:2542-4351, Pages:2593-2605

Grant N, Hawkes A, Mittal S, et al., 2021, Confronting mitigation deterrence in low-carbon scenarios, Environmental Research Letters, Vol:16, ISSN:1748-9326

More Publications