2025 CEQ Annual Report

Air Quality

Air Days              Air Pollutants

Climate Changers

It is estimated that total greenhouse gas (GHG) emissions in 2023 (most recent data available) for all economic sectors increased by about 1.5 percent from 2022 levels to 35 million metric tons of carbon dioxide equivalents (MMTCO2e*) using the electric consumption model. Total GHG emissions in 2023 was approximately 9.9 percent less than the previous ten-year average.

Using the electric generation model, it is estimated that total GHG emissions in 2023 for all economic sectors decreased by 1.8 percent from 2022 levels to 42.0 MMTCO2e. 

The transportation sector is estimated to have accounted for the most GHG emissions in 2023 at 41.7 percent, while the residential, commercial, and industrial sectors accounted for 19.2 percent, 12.2 percent, and 10.7 percent, respectively.³  

Goal: State law set the following goals for GHG emissions: reduce statewide emissions to 10 percent below 1990 levels by 2020, 45 percent below 2001 levels by 2030, and 80 percent below 2001 levels by 2050. NEW! Public Act 25-125, Section 2 established a new goal to reduce GHG emissions to a level at least 65 percent below the level emitted in 2001, including to a level of zero percent from electricity supplied to electric customers in the state by January 1, 2040.

_{Technical Note: Technical Note: * Emissions are reported in terms of carbon dioxide equivalents (CO2e, i.e., CO2 and other gases with equivalent climate warming impact). While carbon dioxide is the primary GHG, emissions of other GHGs are expressed on the basis of their potential to contribute to global warming, relative to carbon dioxide’s potential.} 

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³ _{DEEP, 1990-2023 Greenhouse Gas Emissions Inventory - August 2025; portal.ct.gov/-/media/deep/climatechange/1990-2023-ghg-inventory/deep_ghg_report_1990-2023-final.pdf}