NEW YORK: Power and natural gas prices in Texas and California spiked to multimonth highs this week as homes and businesses cranked up their air conditioners to escape brutal heatwaves.

In Texas, the Electric Reliability Council of Texas (ERCOT), which operates most of the state’s power system, urged consumers on Monday to conserve energy to prevent high demand and generation outages from straining the grid.

In California, the California ISO, which operates most of the state’s grid, told consumers to prepare to conserve energy if needed.

Both grids have imposed rotating outages over the last year to avoid widespread collapses of their power systems - California in August 2020 and Texas in February 2021.

Rotating outages are supposed to leave a limited number of customers without service for short periods of time before switching to another group of customers. But in Texas, ERCOT received criticism after millions of homes and businesses were left in the dark - many for days.

For this week, ERCOT forecast power demand would peak at 70,489 megawatts (MW) on Tuesday up from 70,114 MW on Monday. That compares with the grid’s all-time high of 74,820 MW in August 2019. One MW typically powers about 200 homes on a hot summer day.