This is an excerpt from EERE Network News, a weekly electronic newsletter.

May 12, 2004

Despite a Rough Spring, California Expects No Power Problems this Summer

The operator of California's electrical power grid reported in mid-April that the state should have adequate power resources to meet its peak demand this summer, "barring transmission outages, significant generation outages, natural disasters, or local and/or national catastrophes." The California Independent System Operator (ISO) expects the state's peak power demand to hit 44,422 megawatts this summer, while it expects to have 48,712 megawatts of generation available, plus 75 megawatts of demand response, yielding a power surplus of 2,750 megawatts. The ISO warns, however, that congestion of the transmission lines serving southern California could cause reliability problems there. The ISO also adds an additional caveat to its forecast, warning that "early, extended operation of generating units can result in higher forced outages or encroachment upon environmental limitations, which restrict the number of hours a generating unit can run." See the California ISO's "2004 Summer Assessment" (PDF 720 KB). Download Acrobat Reader.

This summer may go well, but the ISO has already had some difficulties this spring, as unexpectedly high power demands struck while some power plants were still down for maintenance. Heat waves in late March and again on May 3rd caused the ISO to declare power emergencies. The early-May heat wave caused a peak demand of about 40,451 megawatts, and led the ISO to ask Southern California Edison (SCE) to curtail its load by 600 megawatts through voluntary power reductions by commercial users. See the press releases from the California ISO and SCE.