Table 4.08.C. Usage Factors for Utility Scale Storage Generators

  Battery Pumped Storage
Year/Month Time Adjusted Capacity Usage Factor Time Adjusted Capacity Usage Factor
Annual Data
2013 126.7 0.007 22389.3 0.098
2014 155.1 0.017 22477.9 0.102
2015 206.8 0.036 22568.9 0.102
2016 423.0 0.038 22752.7 0.112
2017 632.8 0.068 22791.7 0.114
2018 713.6 0.052 22815.4 0.108
Year 2016
January 364.9 0.038 22683.7 0.092
February 370.9 0.036 22705.7 0.080
March 391.7 0.039 22705.7 0.084
April 398.7 0.040 22705.7 0.086
May 408.7 0.039 22778.7 0.109
June 419.1 0.040 22778.7 0.156
July 439.1 0.039 22778.7 0.159
August 439.1 0.040 22778.7 0.164
September 440.1 0.037 22778.7 0.133
October 442.1 0.037 22778.7 0.101
November 480.1 0.035 22778.7 0.086
December 480.1 0.033 22778.7 0.096
Year 2017
January 562.8 0.069 22753.4 0.102
February 573.8 0.074 22753.4 0.080
March 581.8 0.083 22753.4 0.085
April 611.8 0.076 22753.4 0.095
May 627.7 0.068 22810.4 0.117
June 641.2 0.068 22810.4 0.142
July 643.2 0.062 22810.4 0.169
August 645.4 0.068 22810.4 0.162
September 678.2 0.061 22810.4 0.129
October 679.4 0.066 22810.4 0.102
November 681.4 0.068 22810.4 0.090
December 663.4 0.062 22810.4 0.091
Year 2018
January 643.7 0.052 22785.2 0.098
February 663.5 0.051 22785.2 0.096
March 667.1 0.052 22785.2 0.079
April 681.1 0.050 22785.2 0.082
May 690.6 0.052 22830.2 0.110
June 696.1 0.049 22830.2 0.132
July 742.1 0.056 22830.2 0.155
August 740.1 0.056 22830.2 0.161
September 746.4 0.056 22830.2 0.122
October 748.9 0.050 22830.2 0.094
November 768.9 0.053 22830.2 0.082
December 770.7 0.051 22830.2 0.077

Values are final.
Time adjusted capacity for month rows is the summer capacity of generators in operation for the entire month; units that began operation during the month or that retired during the month are excluded. Time adjusted capacity for year rows is a time weighted average of the month rows.
Usage factors are a comparison of gross generation with available capacity. See the technical note for an explanation of how usage factors are calculated.
Sources: U.S. Energy Information Administration, Form EIA-923, Power Plant Operations Report; U.S. Energy Information Administration, Form EIA-860, 'Annual Electric Generator Report' and Form EIA-860M, 'Monthly Update to the Annual Electric Generator Report.'