IEA (2021), World Energy Model, IEA, Paris https://www.iea.org/reports/world-energy-model
An additional scenario referenced in WEO-2021 is the Sustainable Development Scenario (SDS). As a “well below 2 °C” pathway, the SDS represents a gateway to the outcomes targeted by the Paris Agreement. Like the NZE, the SDS is based on a surge in clean energy policies and investment that puts the energy system on track for key SDGs. In this scenario, all current net zero pledges are achieved in full and there are extensive efforts to realise near-term emissions reductions; advanced economies reach net zero emissions by 2050, China around 2060, and all other countries by 2070 at the latest. Without assuming any net negative emissions, this scenario is consistent with limiting the global temperature rise to 1.65 °C (with a 50% probability). With some level of net negative emissions after 2070, the temperature rise could be reduced to 1.5 °C in 2100.
Since WEO-2020, the SDS also integrates the stimulus packages required for a global sustainable recovery from Covid-19. Investments in the 2021-2023 period are therefore aligned with the Sustainable Recovery depicted in the World Energy Outlook Special Report. To allow for meaningful comparison of the energy drivers and outcomes between the scenarios, the underlying assumptions on public health and economic growth in the SDS are the same as in the STEPS.