Chapter 01 · Climate & transitionEnergy & Transition
Announced Pledges Scenario (APS)
Definition
A scenario of the International Energy Agency's World Energy Outlook, introduced in 2021, which assumes that all recent major national climate announcements — 2030 targets and longer-term net zero or carbon neutrality pledges, whether or not anchored in legislation or NDCs — are met in full and on time. It is an exploratory scenario, not a forecast.
References
Introduced 2021; assumptions (all pledges met in full and on time); WEO-2025 omission pending new NDCs.
APS vs STEPS vs NZE structure; 1.7°C (APS 2023) vs 2.4°C (STEPS) warming outcomes; exploratory vs normative design.
Overview
What it means
The APS sits between the IEA's Stated Policies Scenario (STEPS), which reflects only existing and under-development policies, and the normative Net Zero Emissions by 2050 Scenario, which back-casts from the 1. 5°C goal. The 2023 APS update implied about 1. 7°C of warming by 2100 (50% probability), versus 2. 4°C in STEPS.
The 2025 World Energy Outlook did not include an APS, pending a fuller picture of the new NDC round.
How it is used
Analysts and governments use the APS to show what current promises would deliver if kept — exposing the gap between pledges and Paris-consistent pathways, and between pledges and policies. Comparing APS with NZE identifies the additional measures needed.
Why it matters
The APS quantifies the credibility question at the heart of climate governance: what happens if everyone does what they said. Its difference from STEPS measures the "implementation gap", and from NZE the "ambition gap".