Table 8.9.B. Winter Net Internal Demand, Capacity Resources, and Capacity Margins
by North American Electric Reliability Corporation Assessment Area, 2011 Actual, 2012-2016 Projected
 

Net Internal Demand (Megawatts) -- Winter
  Eastern Interconnection ERCOT Western Interconnection All Interconnections
Period FRCC NPCC Balance of Eastern Region MAPP MISO PJM SERC SPP TRE WECC Contiguous U.S.
Actual 2011 / 2012 39,924 43,806 385,428 4,443 83,946 110,963 147,454 38,622 50,100 107,568 626,826
Projected 2012 / 2013 43,558 46,224 384,172 4,756 72,187 119,222 148,404 39,602 51,319 105,833 631,106
Projected 2013 / 2014 43,049 46,312 386,823 4,858 69,663 121,160 150,160 40,983 50,263 108,029 634,476
Projected 2014 / 2015 44,228 46,284 394,645 4,999 74,965 121,571 151,765 41,345 50,533 109,938 645,628
Projected 2015 / 2016 44,790 46,246 398,806 5,074 75,354 123,711 153,443 41,225 53,378 111,530 654,750
Projected 2016 / 2017 45,297 46,246 403,949 5,335 75,854 125,367 155,580 41,812 54,363 112,361 662,216

 

Capacity Resources (Megawatts) -- Winter
  Eastern Interconnection ERCOT Western Interconnection All Interconnections
Period FRCC NPCC Balance of Eastern Region MAPP MISO PJM SERC SPP TRE WECC Contiguous U.S.
Actual 2011 / 2012 56,466 72,741 544,706 4,960 98,329 170,077 212,063 59,276 69,202 150,091 893,206
Projected 2012 / 2013 54,299 77,919 560,445 5,656 106,643 174,641 214,479 59,028 74,215 147,378 914,257
Projected 2013 / 2014 54,911 79,604 571,643 6,303 106,553 173,925 224,397 60,465 75,444 153,118 934,721
Projected 2014 / 2015 58,001 77,342 572,501 6,338 106,514 172,681 225,810 61,159 75,446 154,411 937,702
Projected 2015 / 2016 56,784 77,379 567,120 6,460 106,577 167,544 225,383 61,156 76,879 157,185 935,347
Projected 2016 / 2017 57,667 75,486 570,417 6,497 106,450 167,623 228,787 61,059 78,968 155,875 938,414

 

Capacity Margin (Percent) -- Winter
  Eastern Interconnection ERCOT Western Interconnection All Interconnections
Period FRCC NPCC Balance of Eastern Region MAPP MISO PJM SERC SPP TRE WECC Contiguous U.S.
Actual 2011 / 2012 29.3% 39.8% 29.2% 10.4% 14.6% 34.8% 30.5% 34.8% 27.6% 28.3% 29.8%
Projected 2012 / 2013 19.8% 40.7% 31.5% 15.9% 32.3% 31.7% 30.8% 32.9% 30.9% 28.2% 31.0%
Projected 2013 / 2014 21.6% 41.8% 32.3% 22.9% 34.6% 30.3% 33.1% 32.2% 33.4% 29.4% 32.1%
Projected 2014 / 2015 23.7% 40.2% 31.1% 21.1% 29.6% 29.6% 32.8% 32.4% 33.0% 28.8% 31.1%
Projected 2015 / 2016 21.1% 40.2% 29.7% 21.5% 29.3% 26.2% 31.9% 32.6% 30.6% 29.0% 30.0%
Projected 2016 / 2017 21.5% 38.7% 29.2% 17.9% 28.7% 25.2% 32.0% 31.5% 31.2% 27.9% 29.4%

Notes:
NERC region and reliability assessment area maps are provided on EIA's Electricity Reliability web page: http://www.eia.gov/cneaf/electricity/page/eia411/eia411.html
Net Internal Demand represent the system demand that is planned for by the electric power industry`s reliability authority and is equal to Internal Demand less Direct Control Load Management and Interruptible Demand.
Capacity Resources: Utility and nonutility-owned generating capacity that is existing or in various stages of planning or construction, less inoperable capacity, plus planned capacity purchases from other resources, less planned capacity sales.
Capacity Margin is the amount of unused available capability of an electric power system at peak load as a percentage of capacity resources.
The Winter peak period begins October 1 and extends through May 31.
Historically the MRO, RFC, SERC, and SPP regional boundaries were altered as utilities changed reliability organizations. The historical data series for these regions have not been adjusted. Instead, the Balance of Eastern Region category was introduced to provide a consistent trend of the Eastern interconnection.
ECAR, MAAC, and MAIN dissolved at the end of 2005. Many of the former utility members joined RFC. Reliability First Corporation (RFC) came into existence on January 1, 2006. RFC submitted a consolidated filing covering the historical NERC regions of ECAR, MAAC, and MAIN.
Source: U.S. Energy Information Administration, Form EIA-411, "Coordinated Bulk Power Supply and Demand Program Report."