Wholesale power prices in Southern California climbed as cloud cover trimmed solar generation, leaving the grid to rely more on higher-priced generation.
Solar panels produced 5,203 megawatts at 11:23 a.m. local time, according to data from the California Independent System Operator Corp. That was down from a day earlier, when output reached a peak of 6,072 megawatts, the most since April 28, Steven Greenlee, a spokesman for the Folsom, California-based network manager, said in a phone interview.
Electricity consumption in the state’s main grid climbed 1.2 percent for the hour from Tuesday.
“Cloud cover is more dense compared to yesterday, when solar reached near-record levels,” Ross Fessenden, a power market analyst at Boston-based Genscape Inc. said by e-mail. “Wind has dropped considerably from yesterday as well.”
Spot wholesale power for the California SP15 hub, serving Los Angeles and San Diego, gained $12.80, or 72 percent, to average $30.64 a megawatt-hour during the hour ended at 11 a.m. local time Wednesday from the same time a day earlier, grid data compiled by Bloomberg show.
Spot power at Northern California’s NP15 hub, which includes deliveries to San Francisco, fell $3.20, or 9.3 percent, to average $31.21 a megawatt-hour.
Average on-peak power in the South traded 31 cents less than the north, narrowing from $10.06 a day earlier, and compared with a three-month average premium for the South of $8.53 a megawatt-hour.
“Variable cloud cover will impede solar generation throughout the bulk of the week,” WSI Corp. in Andover, Massachusetts, said in a note. “Despite the highly beneficial wet weather, the ongoing drought and record low snow pack across the Sierra will continue to hamper hydro generation potential.”