Coal phase-out: researching the research
Using an ensemble analysis to assess coal transition scenarios
A new paper provides a comprehensive assessment of coal transitions in mitigation scenarios consistent with the Paris Agreement.
The Paris climate goal, which aims to keep global warming well below 2 °C, requires a rapid and sustained reduction in global CO2 emissions towards net zero. A rapid phase-out of unabated coal use across all sectors of the world economy is essential to deliver this outcome.
A new paper takes data from more than 1500 publicly available scenarios generated by more than 30 integrated assessment models to categorise coal transition pathways in models, and bridges evidence on technological learning and innovation with historical data of energy systems. The paper’s co-authors include Professors Benjamin Sovacool and Felix Kreutzig from the Bennett Institute.
There are six key findings:
- There are three archetypal coal transitions within Paris-consistent mitigation pathways. About 38% of scenarios are ‘coal phase out’ trajectories and rapidly reduce coal consumption to near zero. ‘Coal persistence’ pathways (42%) reduce coal consumption much more gradually and incompletely. The remaining 20% follow ‘coal resurgence’ pathways, characterised by increased coal consumption in the second half of the century.
- The coal persistence and resurgence archetypes rely on the widespread availability and rapid scale-up of carbon capture and storage technology (CCS).
- These three coal-transition archetypes spread across all levels of climate policy ambition and scenario cycles, reflecting their dependence on model structures and assumptions.
- Most baseline scenarios—including the shared socio-economic pathways (SSPs)—show much higher coal dependency compared to historical observations over the last 60 years.
- Coal-transition scenarios are consistently optimistic about the cost and scalability of CCS technologies, while being pessimistic about the cost and scalability of renewable energy technologies.
- Evaluation against coal-dependent baseline scenarios suggests that many mitigation scenarios overestimate the technical difficulty and costs of coal phase-outs.
More, better research is urgently needed
Phasing out unabated coal is the elephant in the room of climate change mitigation. These results from a large ensemble of mitigation scenarios suggest that an early coal phase-out is cost-effective.
Keeping the Paris climate goals within reach requires the organisation of a swift global phase-out of unabated coal. It has to happen earlier and faster than the other major fossil fuel transitions away from oil and gas.
Therefore, it is surprising that evidence on coal phase-out dynamics in long-term mitigation scenarios has not been assessed comprehensively in IPCC reports and only few older studies look at these dynamics in more detail.
The paper recommends using up-to-date cost data and evidence about innovation and diffusion dynamics of different groups of zero or low-carbon technologies. Revised SSP quantifications need to incorporate projected technology learning and consistent cost structures, while reflecting recent trends in coal consumption.
Read the full findings
This article is a summary of Coal transitions—part 2: phase-out dynamics in global long-term mitigation scenarios published in IOPscience Environmental Research Letters, Volume 19, Number 3, and authored by:
Jan C Minx, Jerome Hilaire, Finn Müller-Hansen, Gregory Nemet, Francesca Diluiso, Robbie M Andrew, Ceren Ayas, Nico Bauer, Stephen L Bi, Leon Clarke, Felix Creutzig, Ryna Yiyun Cui, Frank Jotzo, Matthias Kalkuhl, William F Lamb, Andreas Löschel, Niccolò Manych, Malte Meinshausen, Pao-Yu Oei, Glen P Peters, Benjamin Sovacool, Jan C Steckel, Sebastian Thomas, Annabelle Workman and John Wiseman.
Funding
J C M, F D, J C S, N M, S L B and N B acknowledge funding from the German Federal Ministry of Education and Research within the PEGASOS project (Grant Reference: 01LA1826A). P O acknowledges funding from the German Federal Ministry of Education and Research within the FFF (01LA1810A) and CoalExit project (01LN1704A). W F L acknowledges funding from the German Federal Ministry of Education and Research (IPCC-AR6-III- 2, Grant Reference: 01LG1910A). S L B also acknowledges funding from Horizon Europe (RESCUE, Grant Reference: 101056939). J C M, F M H and W F L also acknowledge funding by the European Research Council (ERC) under the European Union’s Horizon 2020 Framework Programme as part of the project ‘GeoEngineering and NegatIve Emissions pathways in Europe’ (GENIE) (Grant agreement No. 951542). R M A and G P P acknowledge funding from the European Union’s HORIZON EUROPE Research and Innovation Programme under Grant Agreement No. 101056306 (IAM COMPACT).
