Table 4.14. Fuel-Switching Capacity of Operable Generators Reporting Natural Gas as the Primary Fuel,
by Year of Initial Commercial Operation, 2015 (Megawatts, Percent)

Year of Initial Commercial Operation Number of Natural Gas-Fired Generators Reporting the Ability to Switch to Petroleum Liquids
Net Summer Capacity of Natural Gas-Fired Generators Reporting the Ability to Switch to Petroleum Liquids
Fuel Switchable Net Summer Capacity Reported to Have No Factors that Limit the Ability to Switch to Petroleum Liquids
Pre-1970 303 13,016.4 4,924.1
1970-1974 314 16,772.9 6,131.3
1975-1979 97 10,685.0 2,302.8
1980-1984 50 1,621.3 210.5
1985-1989 89 2,842.1 251.5
1990-1994 215 12,156.2 1,546.4
1995-1999 131 9,617.8 1,931.5
2000-2004 397 38,870.8 7,817.8
2005-2009 126 16,007.7 1,132.9
2010-2014 94 10,588.4 89.8
2015 15 601.0 5.6
Total 1,831 132,779.6 26,344.2

Notes: Petroleum liquids include distillate fuel oil (all diesel and No. 1, No. 2, and No. 4 fuel oils), residual fuel oil (No. 5 and No. 6 fuel oils and bunker C fuel oil), jet fuel, kerosene, waste oil, and propane.
Source: U.S. Energy Information Administration, Form EIA-860, "Annual Electric Generator Report."