With electricity reserves forecast to fall below 7% Thursday, the California Independent System Operator (ISO) declared a Stage 1 emergency for the third day in a row Thursday. The ISO issued the warning notice and requested supplemental energy bids of up to 3,000 Mw.
It blamed high temperature and short supply. Power plants totaling 3,964 Mw of electricity are off line today due to mechanical failure or planned maintenance that could not be postponed, the ISO said. Fires affecting power supplies in southern California Wednesday have been contained and are not a factor in today's resource shortfall, it said.
The ISO said electricity consumption is expected to peak about 4 p.m. PST, drawing more than 40,482 Mw from the ISO-controlled power grid. At 1:30 p.m., loads already totaled 39,197 Mw.
The ISO said the Stage 1 alert is in effect through 7 p.m.
If conservation measures are insufficient in lowering the demand for power, the ISO said load management programs that implement voluntary curtailments of power are probable. On Wednesday, the ISO called a Stage 2 alert after reserves dropped below 5%.
At this level, large commercial customers that have signed up to voluntarily curtail power during high demand days are asked to begin shedding load.