Phase out coal and unabated fossil gas electricity generation

Targets were designed by Climate Action Tracker (CAT) through a combination of top-down and bottom-up methods to establish near- and long-term power generation targets. CAT first identified modeled pathways that limit global temperature rise to 1.5 degrees C (2.7 degrees F) with no or limited overshoot from the International Panel on Climate Change (IPCC) Sixth Assessment Report and then filtered them according to four pieces of criteria: 

• Scenarios were published in or after 2018;             
• Scenarios have good regional resolution;             
• Bioenergy with carbon capture and sequestration deployment is restricted to an average of 5 gigatonnes of carbon dioxide per year (GtCO2/yr) from 2040 to 2060, and carbon removal from afforestation and reforestation is limited to an average of 3.6 GtCO2/yr from 2040 to 2060 and to an average of 4.4 GtCO2/yr from 2050 to 2100; and            
• Scenarios are consistent with achieving net-zero greenhouse gas (GHG) emissions in the second half of the century, as stated in Article 4.1 of the Paris Agreement.

The median value from these scenarios formed the less ambitious bound of the power sector targets’ ranges, though CAT made several key adjustments to this global median to better account for equity considerations and feasibility constraints that will likely impact many developing countries’ capacities to transform the power sector. These included: assuming developed countries can reduce fossil fuels at the 75th percentile rate rather than the median rate, allowing developing countries to reduce coal at a slightly slower rate; limiting new fossil gas generation capacity and reallocating GHG savings to coal-fired power fleets; and increasing renewable energy generation to fill gaps in generation as a result of the previous adjustments. CAT then combined this analysis of modeled pathways from integrated assessment models (IAMs) with a bottom-up review of global energy system modeling efforts, including assessments of the feasibility and cost of different technologies. It compared targets derived from this bottom-up review with those developed using the 1.5 degrees C (2.7 degrees F) scenarios from IAMs (which served as a GHG emissions budget constraint). Using the adjusted median value from this filtered set of IAM scenarios as the less ambitious bound of the target range ensured compatibility with the 1.5 degrees C (2.7 degrees F) global temperature rise limit, while deriving the more ambitious bound of the target range from the bottom-up review provided a feasibility constraint on the target.