The California Independent System Operator issued a statewide Flex Alert, a call for voluntary electricity conservation from 4 p.m. to 9 p.m., due to high temperatures pushing up energy demand and tightening available power supplies.
Flex Alerts could also be issued Sept. 4 and Sept. 5.
Labor Day is expected to strain the state's power grid the most.
If things get bad, there's potential for rolling blackouts.
The full statement from Patterson reads:
"Labor Day weekend is going to be the holiday that Californians wake up to the reality that the ruling party in the state of California has created an electricity grid that is increasingly unreliable, without the necessary supply to meet the demand. A grid that is increasingly costly for those who can least afford it.
"We are very quickly coming to a place where we're living like a third world country, where we can't use our electricity when we need it, and if we do need it, we might very well crash the grid. If we do need to use it, it will be so expensive that we cannot afford it.
"There was once a California where our electricity grid was reliable, you could go to the air conditioner, you could go to your washer or dryer and turn it on and do what you needed to do reliably and affordably. Those days are gone. We are facing the stark reality for the ruling party to be so adamant in their ideology about saving the planet that they are crashing the grid.
"This state needs to turn around, change its policy and recognize that electricity affordability and reliability is a fundamental right of the people of California. We should not be told you can't use it when you need it. It's a failed policy. The Governor and the Democrats in the Legislature have to own up to it and they have to change direction, or it's going to get worse over time."
Gov. Gavin Newsom will discuss the heat wave expected to impact California and the West Coast, lasting through Labor Day weekend until next Wednesday.