There has been a rapid increase in the last year of governments pledging to reduce greenhouse gas emissions to zero by 2050. To date, such measures cover about 70 percent of global GDP and CO₂ emissions. However, less than a quarter of government announcements are also set in national legislation, and few are yet backed by specific measures or policies to achieve them in full and on time.
The Stated Policies Scenario (STEPS), a benchmark prepared by the International Energy Agency (IEA) , takes into account only specific policies that are in place or have been announced by governments. Annual CO₂ emissions related to energy and industrial processes increase from 34 billion metric tons (Gt) in 2020 to 36 billion metric tons (Gt) in 2030 and remain around this level until 2050. If emissions continue on this trajectory, with similar changes in nonenergy-related GHG emissions, this would lead to a temperature increase of about 2.7°C by 2100 (with a 50 percent probability). Renewables will be able to provide nearly 55 percent of global electricity generation in 2050 (up from 29 percent in 2020), but clean energy transitions are lagging in other sectors.
The Announced Pledges Case (APC), a metric also established by the IEA for monitoring climate trends, assumes that zero-emissions targets are met in full and on time, whether or not they are supported by specific legislation.
Global CO₂ emissions related to energy and industrial processes are projected to fall to 30 billion tons in 2030 and 22 billion tons in 2050. Extending this trajectory, with similar action on greenhouse gas emissions not directly related to energy production, would lead to a temperature increase in 2100 of about 2.1°C. Energy efficiency, electrification, and replacing coal with low-emission sources play a central role in achieving zero emissions in the APC metric, especially in the period to 2030. The relative contributions of nuclear, hydrogen, bioenergy, and CCUS vary from country to country, depending on circumstances.
The divergence in trends between the APC measurement and the STEPS shows the difference that current commitments could generate, while emphasizing the need for concrete policies and short-term plans that are consistent long-term energy policies. However, the APC also clearly highlights that current zero commitments, even if delivered in full, fall well short of what is needed to achieve Carbon Neutrality by 2050.