The Net Zero Emissions by 2050 Scenario is normative, in that it is designed to achieve specific outcomes – an emissions trajectory consistent with keeping the temperature rise in 2100 below 1.5 °C (with a 50% probability), universal access to modern energy services and major improvements in air quality – and shows a pathway to reach it.
[2] The Announced Pledges Scenario, and the Stated Policies Scenario are exploratory, in that they define a set of starting conditions, such as policies and targets, and then see where they lead based on model representations of energy systems, including market dynamics and technological progress.
The scenarios are not predictions but enable policy-makers and other readers to compare different possible versions of the future and the levers and actions that produce them, with the aim of stimulating insights about the future of global energy.
[2] Since 1993, the IEA has provided medium- to long-term energy projections using a continually-evolving set of modelling tools.
This model is now the principle tool used to generate detailed sector-by-sector and region-by-region long-term scenarios for the World Energy Outlook and other IEA publications.