Combined-cycle plants reverse four-year trend

Eight new natural gas-fired combined-cycle gas turbine (CCGT) power plants have come online or will come online in the United States this year, adding 7775 MW of electric generating capacity to the U.S. electric grid, according to information from the U.S. Energy Information Administration’s (EIA) Monthly Electric Generator Inventory.

The eight projects reverse four years of decline in CCGT plant startups, EIA said. CCGT electric generating capacity is expected to reach almost 290 GW by yearend, or 24% of total U.S. generating capacity.

CCGT plants are one of four major sources of natural gas-fired power generation and the single largest source of both electric generating capacity and electricity generation. CCGT plants use both a natural gas and a steam turbine.

Output from the U.S. CCGT fleet will likely rise from the 1,326,278 GWh it generated in 2021, which was 32% of total electricity generation last year. Shares of coal-fired generation (22%) ranked second and nuclear sources (19%) were third in terms of electric-generating capacity and electricity generation in 2021.

About half of the existing U.S. CCGT fleet currently operating entered service between 2000 and 2006, EIA said. Although annual additions of CCGT capacity have risen steadily during the past two decades, the additions this year are about 80% below the record CCGT capacity additions in 2002 and 2003.

Seven of the eight CCGT plants opening this year are located either in the upper Midwest or in Florida. The new plants are being built in these areas to meet rising demand for electricity and to replace retiring coal-fired power plants.

In the PJM Interconnection region, three new CCGT plants are opening this year, totaling 3,918 MW of capacity. These additions will help replace the 5,346 MW of coal-fired capacity in PJM that is retiring this year, followed by another 3,774 MW of coal capacity set to retire next year.

In Florida, the 2,222 MW of new CCGT capacity will replace 1,486 MW of coal-fired capacity retiring this year. In Michigan (in the MISO region), 1,403 MW of new CCGT capacity will replace the 1,560 MW of existing coal-fired generating capacity that will retire this year.

EIA said it expects 4,215 MW of CCGT capacity will be added in 2023, when five new plants are slated to open. All of those facilities are currently under construction are expected to begin operations before the end of 2023.