Comparing Q1 2021 to Q1 2020

The Carnegie Mellon Power Sector Carbon Index provides a comprehensive picture of the carbon intensity of electricity production in the during the previous 12 months and over an extended period to 2001. The CMU index also provides a summary of how much electricity generation is from coal, natural gas, nuclear, and renewables. According to the Carnegie Mellon Power Sector Carbon Index, U.S. power plant emissions averaged 834 lb CO₂ per MWh in the first quarter of 2021, which was up 10 percent from the same time frame in 2020.

Comparing performance in 2021 to 2005

The Power Sector Carbon Index for Q1 of 2021 was 37% lower than in the annual value in 2005, from 1,321 lb CO₂ per MWh to 834 lb CO₂ per MWh (or 599 to 379 g CO₂ per kWh). As of Q1 of 2021, the rolling annual average carbon intensity was 824 lb CO₂ per MWh (or 374 g CO₂ per kWh), which is 38% lower than the annual value in 2005. Total annual rolling CO₂ emissions were 1,522 million metric tonnes, which was 37% lower than in 2005.

Highlights of the 2021 Q1 results

• Total generation was up 2% in 2021 Q1 (997 million MWh) when compared to 2020 Q1 (974 million MWh).
• Coal generation was up 35% in 2021 Q1 (232 million MWh) when compared to 2020 Q1 (172 million MWh). Coal represented 23% of total generation in 2021 Q1
• Natural Gas generation was down 10% in 2021 Q1 (342 million MWh) when compared to 2020 Q1 (382 million MWh). Natural Gas represented 34% of total generation in 2021 Q1
• Hydro generation was down 7% in 2021 Q1 (70 million MWh) when compared to 2020 Q1 (75 million MWh). Hydro represented 7% of total generation in 2021 Q1
• Wind generation was up 10% in 2021 Q1 (97 million MWh) when compared to 2020 Q1 (87 million MWh). Wind represented 10% of total generation in 2021 Q1
• Solar generation was up 24% in 2021 Q1 (31 million MWh) when compared to 2020 Q1 (25 million MWh). Solar represented 3% of total generation in 2021 Q1
• Nuclear generation was down 3% in 2021 Q1 (198 million MWh) when compared to 2020 Q1 (204 million MWh). Nuclear represented 20% of total generation in 2021 Q1
• Other generation was up 2% in 2021 Q1 (10 million MWh) when compared to 2020 Q1 (10 million MWh). Other represented 1% of total generation in 2021 Q1
• Other Renewables generation was down 4% in 2021 Q1 (18 million MWh) when compared to 2020 Q1 (19 million MWh). Other Renewables represented 2% of total generation in 2021 Q1