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Saturday, June 5, 2021

The IEA Roadmap to Net Zero: A critical review

As promised I read the IEA report carefully and listed some comments, questions and suggestions. The objective was to condense the 224-page document for a broader public and flag some concerns. A worthy objective... but the result, at this stage, is still 13 pages (excluding an Appendix for the layperson outlining energy units and some basic combustion chemistry). And while I am sure my readers are always fascinated by what I write, 13 pages is still a long read. So I have attempted to summarise my summary in a one-page Executive Summary. This is posted below; and the full document is available in PDF format by clicking here

The Executive Summary follows; I hope you enjoy reading, whichever version you choose, and I look forward to your comments and discussion. 

The IEA report “Net Zero by 2050, A Roadmap for the Global Energy Sector” made headlines for stating that no new oil or gas exploration is needed if we hope to keep to +1.5°C by 2050. Essentially this saw the OECD agree with environmentalist’s calls to “leave it in the ground”. Other policies will upset environmentalists as much this has upset Big Oil. The world economy is assumed 40% larger in 2050 while using 7% less energy; the question is whether energy savings could be 10% or more?

Energy production and use emitted 33.9 Gt CO2 in 2020, about 75% of the total. The IEA predicts cumulative savings to 2050 of 460 Gt CO2, consistent with IPCC guidelines that we emit no more than another 500 Gt CO2.

Solar PV and wind power are commercial today and provide close to half these savings. But challenges remain with several other technologies needed. 

Biomass power allows stranded coal assets to continue running; it also displaces liquid transportation fuels and natural gas in pipelines. But carbon neutrality of biomass is under threat from unknown levels of new climate-driven emissions from forest fires, insect infestations, floods and desertification. Biomass for power generation contributes to grid stability, but other options could be reviewed. 

Carbon capture (CCUS) is essential for cement kilns, where emissions are not fuel-related, and for thermally-generated power; when the fuel is carbon-neutral biomass, CCUS generates a double-counting benefit. But CCUS requires pipelines to store CO2. Reduced hydrogen from natural gas and more rapid decommissioning of coal-fired plants would reduce the need for CCUS. (Direct air capture located next to CO2 storage would not need pipelines.) 

Nuclear power, which is expected to double, is needed to offload other technologies and to stabilise the grid. But stranded coal assets along with smarter grids and more interconnections will also contribute to grid stability

Energy efficiency increases as world energy use per capita declines from 80 GJ to 56 GJ. The IEA posits a rapid improvement to 2030, with smaller gains to 2050. Increasing efficiencies will be challenging, but small changes early in the process will have a large compounded impact later on.

Hydrogen is needed for industrial combustion, but distribution networks for road transport will be fraught with safety problems. Ideally hydrogen should only be used where it produced, not distributed.

Electric vehicles are more efficient than internal combustion by a factor of about 3, and contribute to transportation use dropping 22% to 80 EJ. A more aggressive approach to urban transportation solutions, driven by gridlock and not climate change, could reduce this through fewer private vehicles. Furthermore, the need for lithium and battery recycling technologies are huge challenges.

Housing space per capita needs to grow, especially in poor countries. But new floor space in urban settings may increase sprawl. Societal changes to reduce sprawl could reduce the average space per capita and the need for cars in suburbs in a synergistic fashion, especially in the developed world.

Overall, it is not surprising that the IEA, as an arm of the OECD, has not put a lot of stock in societal changes that might prove a difficult political sell. This is critical: as the best vaccine is the one in your arm, the best climate change policy is the one that gets implemented, even if it is not technically the best or fastest one, because it is better than no policy. A new publication (Mark Jaccard, The Citizen’s Guide to Climate Success: Overcoming myths that hinder progress. Cambridge University press, 2020) describes this well, and is very highly recommended, whether the reader tackles the Roadmap or not.


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