| Table 8.8.A. Summer Net Internal Demand, Capacity Resources, and Capacity Margins by North American Electric Reliability Assessment Area, |
| 2001 - 2011, Actual |
| Net Internal Demand (Megawatts) -- Summer | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Eastern Interconnection | ERCOT | Western Interconnection | All Interconnections | |||||||||||||
| Period | FRCC | NPCC | Balance of Eastern Region | ECAR | MAAC | MAIN | MAPP | MISO | MRO | PJM | RFC | SERC | SPP | TRE | WECC | Contiguous U.S. |
| 2001 | 38,932 | 55,888 | 417,613 | 100,235 | 54,015 | 53,032 | -- | -- | 27,125 | -- | -- | 144,399 | 38,807 | 55,106 | 107,294 | 674,833 |
| 2002 | 37,951 | 55,164 | 430,396 | 101,251 | 54,296 | 53,267 | -- | -- | 28,825 | -- | -- | 154,459 | 38,298 | 55,833 | 117,032 | 696,376 |
| 2003 | 40,387 | 53,936 | 422,253 | 98,487 | 53,566 | 53,617 | -- | -- | 28,775 | -- | -- | 148,380 | 39,428 | 59,282 | 120,894 | 696,752 |
| 2004 | 42,243 | 51,580 | 419,349 | 95,300 | 52,049 | 50,499 | -- | -- | 29,094 | -- | -- | 153,024 | 39,383 | 58,531 | 121,205 | 692,908 |
| 2005 | 45,950 | 57,402 | 455,594 | -- | -- | -- | -- | -- | 38,266 | -- | 190,200 | 186,049 | 41,079 | 59,060 | 128,464 | 746,470 |
| 2006 | 45,345 | 60,879 | 469,639 | -- | -- | -- | -- | -- | 40,661 | -- | 190,800 | 196,196 | 41,982 | 61,214 | 139,402 | 776,479 |
| 2007 | 46,434 | 58,221 | 465,229 | -- | -- | -- | -- | -- | 40,249 | -- | 177,200 | 205,321 | 42,459 | 61,063 | 135,839 | 766,786 |
| 2008 | 44,660 | 59,896 | 447,629 | -- | -- | -- | -- | -- | 38,857 | -- | 169,155 | 196,711 | 42,906 | 61,049 | 130,916 | 744,151 |
| 2009 | 46,263 | 55,730 | 424,714 | -- | -- | -- | -- | -- | 35,849 | -- | 161,241 | 186,507 | 41,117 | 63,518 | 122,881 | 713,106 |
| 2010 | 45,522 | 56,232 | 453,436 | -- | -- | -- | 4,493 | 100,963 | -- | 135,142 | -- | 160,896 | 51,942 | 64,378 | 126,944 | 746,513 |
| 2011 | 44,798 | 62,313 | 466,360 | -- | -- | -- | 4,641 | 98,290 | -- | 146,443 | -- | 161,995 | 54,991 | 68,416 | 117,755 | 759,642 |
| Capacity Resources (Megawatts) -- Summer | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Eastern Interconnection | ERCOT | Western Interconnection | All Interconnections | |||||||||||||
| Period | FRCC | NPCC | Balance of Eastern Region | ECAR | MAAC | MAIN | MAPP | MISO | MRO | PJM | RFC | SERC | SPP | TRE | WECC | Contiguous U.S. |
| 2001 | 42,290 | 63,760 | 487,950 | 113,136 | 59,533 | 65,950 | -- | -- | 32,271 | -- | -- | 171,530 | 45,530 | 70,797 | 124,193 | 788,990 |
| 2002 | 43,342 | 66,208 | 504,357 | 119,736 | 63,619 | 67,025 | -- | -- | 34,259 | -- | -- | 172,485 | 47,233 | 76,849 | 142,624 | 833,380 |
| 2003 | 46,806 | 70,902 | 513,382 | 123,755 | 65,897 | 67,410 | -- | -- | 33,287 | -- | -- | 177,231 | 45,802 | 74,764 | 150,277 | 856,131 |
| 2004 | 48,579 | 71,532 | 526,454 | 127,919 | 66,167 | 65,677 | -- | -- | 35,830 | -- | -- | 182,861 | 48,000 | 73,850 | 155,455 | 875,870 |
| 2005 | 50,200 | 72,258 | 532,917 | -- | -- | -- | -- | -- | 46,792 | -- | 220,000 | 219,749 | 46,376 | 66,724 | 160,026 | 882,125 |
| 2006 | 50,909 | 73,095 | 534,270 | -- | -- | -- | -- | -- | 50,116 | -- | 214,693 | 223,630 | 45,831 | 70,664 | 162,288 | 891,226 |
| 2007 | 53,027 | 73,771 | 543,608 | -- | -- | -- | -- | -- | 47,259 | -- | 213,544 | 234,232 | 48,573 | 75,912 | 168,080 | 914,397 |
| 2008 | 51,541 | 75,894 | 539,936 | -- | -- | -- | -- | -- | 48,180 | -- | 215,477 | 228,169 | 48,110 | 74,274 | 167,860 | 909,504 |
| 2009 | 49,239 | 78,639 | 559,823 | -- | -- | -- | -- | -- | 47,529 | -- | 215,700 | 247,400 | 49,194 | 76,280 | 152,467 | 916,449 |
| 2010 | 53,370 | 67,569 | 570,396 | -- | -- | -- | 7,210 | 131,691 | -- | 167,647 | -- | 200,511 | 63,337 | 73,857 | 158,407 | 923,599 |
| 2011 | 54,340 | 72,277 | 549,067 | -- | -- | -- | 5,244 | 110,611 | -- | 170,066 | -- | 201,103 | 62,044 | 69,595 | 147,147 | 892,426 |
| Capacity Margin (Percent) -- Summer | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Eastern Interconnection | ERCOT | Western Interconnection | All Interconnections | |||||||||||||
| Period | FRCC | NPCC | Balance of Eastern Region | ECAR | MAAC | MAIN | MAPP | MISO | MRO | PJM | RFC | SERC | SPP | TRE | WECC | Contiguous U.S. |
| 2001 | 7.9% | 12.3% | 14.4% | 11.4% | 9.3% | 19.6% | -- | -- | 15.9% | -- | -- | 15.8% | 14.8% | 22.2% | 13.6% | 14.5% |
| 2002 | 12.4% | 16.7% | 14.7% | 15.4% | 14.7% | 20.5% | -- | -- | 15.9% | -- | -- | 10.5% | 18.9% | 27.3% | 17.9% | 16.4% |
| 2003 | 13.7% | 23.9% | 17.8% | 20.4% | 18.7% | 20.5% | -- | -- | 13.6% | -- | -- | 16.3% | 13.9% | 20.7% | 19.6% | 18.6% |
| 2004 | 13.0% | 27.9% | 20.3% | 25.5% | 21.3% | 23.1% | -- | -- | 18.8% | -- | -- | 16.3% | 18.0% | 20.7% | 22.0% | 20.9% |
| 2005 | 8.5% | 20.6% | 14.5% | -- | -- | -- | -- | -- | 18.2% | -- | 13.5% | 15.3% | 11.4% | 11.5% | 19.7% | 15.4% |
| 2006 | 10.9% | 16.7% | 12.1% | -- | -- | -- | -- | -- | 18.9% | -- | 11.1% | 12.3% | 8.4% | 13.4% | 14.1% | 12.9% |
| 2007 | 12.4% | 21.1% | 14.4% | -- | -- | -- | -- | -- | 14.8% | -- | 17.0% | 12.3% | 12.6% | 19.6% | 19.2% | 16.1% |
| 2008 | 13.4% | 21.1% | 17.1% | -- | -- | -- | -- | -- | 19.3% | -- | 21.5% | 13.8% | 10.8% | 17.8% | 22.0% | 18.2% |
| 2009 | 6.0% | 29.1% | 24.1% | -- | -- | -- | -- | -- | 24.6% | -- | 25.2% | 24.6% | 16.4% | 16.7% | 19.4% | 22.2% |
| 2010 | 14.7% | 16.8% | 20.5% | -- | -- | -- | 37.7% | 23.3% | -- | 19.4% | -- | 19.8% | 18.0% | 12.8% | 19.9% | 19.2% |
| 2011 | 17.6% | 13.8% | 15.1% | -- | -- | -- | 11.5% | 11.1% | -- | 13.9% | -- | 19.4% | 11.4% | 1.7% | 20.0% | 14.9% |
| 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 Summer peak period begins on June 1 and extends through September 30. 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. N/A - Not Available Source: U.S. Energy Information Administration, Form EIA-411, "Coordinated Bulk Power Supply and Demand Program Report." |