Image Credit: The Autonomous University of Barcelona

A low-carbon energy transition typically produces 195 gigatons of CO2 emissions, which correspond to an additional 0.1 °C of global warming.

These are the findings of a study conducted by researchers Aljoa Slamerak, Giorgos Kallis, and Daniel O’Neill at the University of Leeds and the Institute of Environmental Science and Technology of the Universitat Autònoma de Barcelona (ICTA-UAB) and published in Nature Communications.

The authors demonstrate that even though decarbonization has significant energy emissions, the advantages still outweigh the disadvantages. It is better if economies can decarbonize and use less energy as soon as possible.

"Although the existing IPCC literature provides a range of emissions pathways compatible with 1.5 °C of global warming, it has so far remained unclear how much of these emissions will be tied to the transition, and how much of the emissions will remain for societal activities, such as transportation."

Aljoša Slameršak, Study Lead Author and Researcher, Institute of Environmental Science and Technology, Universitat Autònoma de Barcelona

Slameršak added, “Emissions associated with the transition are substantial. However, the overall climate impact of these emissions is still small compared to the emissions avoided by rapid climate action over the long term. The main problem is not the climate impacts of the transition, but the impacts of inaction given how close to overshooting 1.5 °C we currently are.”

Major financial, energy, and material investments will be necessary for a low-carbon energy transition. The transition itself may end up being a significant source of emissions because the world economy is still reliant on fossil fuels.

According to their calculations in this study, the emissions related to the transition will be between 70 GtCO2 and 395 GtCO2, or roughly 2–11 times the total global emissions in 2021.

"Not all scenarios of a low-carbon energy transition are alike. Scenarios with low energy use and lots of renewable energy have much lower emissions associated with the transition. Other scenarios, however, that continue relying on fossil fuels, in the hope of sucking carbon out of the atmosphere later in this century, have a lot of emissions linked to the transition."

Giorgos Kallis, Study Co-Author and ICREA Research Professor, Institute of Environmental Science and Technology, Universitat Autònoma de Barcelona

According to Kallis, governments should prioritize reducing energy use if they are serious about combating climate change.

“Relying on unproven solutions such as so-called ‘negative emissions’ is a risky strategy, not only because of the emissions that they themselves will cause,” Kallis added.

The authors discover that a low-carbon energy transition would not necessarily result in a decrease in the efficiency of energy provisioning, contrary to what has been argued in earlier studies.

Energy system efficiency decreases in scenarios where fossil fuels with carbon capture and storage and biofuels are used. Still, it stays the same or even improves when renewable energy is prioritized.

"Our study shows that any viable pathway for avoiding dangerous climate change requires a decrease in energy use during the initial push for the transition. Continued growth in energy consumption is simply incompatible with the goal of a safe climate."

Daniel O’Neill, Study Co-Author and Associate Professor, Ecological Economics, University of Leeds