Most of the nameplate capacity came
from generators using coal (45.8 percent), natural gas (22.7 percent), nuclear energy (14.0 percent),
wind (10.0 percent), petroleum (3.9 percent), and hydroelectric power (3.6 percent).
Net metered renewable installations are not included in the graphs and table since individual
projects are not reported; hence, no energy sources are reported.
The Units and Capacity by Energy Source and Year of Initial Operation report,
the Generating Units report, and the Annual Electricity Generation
report are available for additional information.
A Note About Nameplate Capacity
Summer capacity and winter capacity are sometimes greater than nameplate capacity. The nameplate gives the capacity
rating of the generator when it operates at certain temperatures, pressures, and power factors. With some modifications
and with some margins that are built into generators, it is possible to exceed its nameplate. It is not uncommon for a
generator to exceed its nameplate. The nameplate is usually not replaced and, in this case, the summer and winter
capacity is often much higher than the nameplate value. Normally, you expect summer and winter capacity to be below
nameplate capacity and in most cases they are.