SAN DIEGO (KGTV) – Another heat wave in the forecast could leave Californians in the dark this weekend.
San Diego Gas and Electric is preparing for a hot weekend as high temps are expected to cause more strain on the power grid.
Energy officials are hoping to avoid a repeat of last month when rolling blackouts swept through the state for the first time in 11 years.
The California Independent System Operator, or CAISO, was forced to order blackouts in response to high demand.
“For the grid to operate, demand on the grid needs to be matched evenly with supply,” said Helen Gao with SDG&E.
Ahead of the heat this weekend, SDG&E meteorologists are closely monitoring conditions.
At this point, CAISO says they haven’t told SDG&E to prepare for rotating outages over the weekend. CAISO says it plans to issue a Flex Alert, which it says is a voluntary call for conservation.
CAISO said the recent rotating outages were the result of a number of factors, including generation units being out of service, reduction of the amount of energy California was able to import from other states, and a sudden drop in wind energy.
If CAISO issues a flex alert, the power company will activate their demand response programs. It encourages customers to cut back on energy use to reduce strain on the grid.
Outages would only be ordered by CAISO as a last resort.
On Tuesday, the State Water Resource Control Board took action to prevent more outages in the future. They’re now along four gas power plants to continue operations past 2020. They were set to stop production as California transitions to cleaner energy sources.
The extended deadline is expected to ease the strain on current systems while new energy and storage resources are being built.
If an outage is planned for a neighborhood, SDG&E says they try to give all customers a heads up before the lights go out.
How these rolling outages work
Rolling outages are a method that CA ISO uses to take the load off of California's power grid. When the state says the grid is under too much stress, each utility in the state has a percentage of electricity that needs to be taken off of the grid to meet whatever wattage CA ISO is aiming for, according to SDG&E. That amount that a utility will be asked to cut during these rolling blackouts is approved with CA ISO regulators every year.
SDG&E determines which neighborhoods will be impacted by creating a list of blocks. Each of those blocks accounts for about 25 megawatts of electricity. Once CA ISO tells SDG&E how much power it needs to cut, SDG&E goes down that list from the top, de-energizing blocks until it is told to stop.
The next day, the company picks up where it left off on the list, so that the same neighborhoods aren't affected every night. Once SDG&E goes through its entire list, it starts at the top again.
Outages can last up to an hour but can also be relatively quick. Saturday, the first block de-energized lasted for about 17 minutes, according to the company.
What you can do to help
To avoid rolling blackouts, officials say the best way is to take energy conservation seriously. Because these outages are issued by the state, conservation is needed by all Californians in these instances.
Officials recommend setting the thermostat at 78 degrees, turning off unnecessary lights and electronics, and using appliances before 3 p.m. to help save power.
During power shutoffs, SDG&E suggests customers turn off air conditioners, keep refrigerator and freezer doors closed, and reduce their water use due to the need for electricity to pump and process water. For electric vehicle owners, charging should be delayed if possible until after the emergency shutoffs, SDG&E said.
SDG&E offers more safety tips to keep in mind during an outage here.