OAKLAND, Calif. (KTVU) - The operators of California's power grid issued a preliminary report on rolling blackouts in August that impacted 800,000 homes and businesses.
During a heatwave on Aug. 14 and 15, the California Independent System Operator (ISO) ordered utilities to cut off electricity to due to an overwhelming demand for power. When that happened, some generators sent power out of the state.
University of California, Berkeley energy economist and ISO board member Severin Borenstein said based on that report it appears that "some of the energy was being exported and that's not unusual."
On most days, California has enough electricity makers to supply the state because grid operators regularly, easily, and economically buy any extra needed power from out of state suppliers. These days, however, California relies much more on solar and wind power than greenhouse gas-emitting fossil fuel power plants.
"This was a very unusual event. It was an extreme temperature event," said Borenstein.
But one consumer advocate says more transparency is needed.
"This was not the hottest. This was not the greatest energy demand and so what needs to happen is we need an investigation by an independent authority like the attorney general's office which is what The Utility Reform Network (TURN) recommended to get to the bottom of who's at fault, why ISO did not do the proper planning, and why there were plants mysteriously offline," said TURN's Director Mark Toney.
Power grid operators said three components caused the blackouts. First, extreme heat covered the entire west, which increased the electricity demand, especially for air conditioning everywhere.
"The peak demand hour, we did OK. The problem was a couple of hours later when the sun set and demand wasn't maybe quite as high but it was still it was very very high," said Borenstein.
When the sun set, the entire solar power system went offline as did a natural gas power plant that was supposed to pick up the slack.
"This isn't a problem with solar. It's a problem with planning for when solar is going to be produced," said Borenstein.
Second, with so many fossil-fueled power plants now retired, the remaining fossil power plants, plus wind and hydroelectricity, could not meet the demand.
Third, some companies and agencies that supply power to consumers and businesses, underestimated how much power to order to meet the increasing demand.
"Some of them did not demand enough electricity to be produced the next day as the actually needed," said Borenstein.
So, as rolling blackouts happened, some California generators exported power to other states that had ordered it from them the day before.
"There are generators in the state who have contracts to sell to users out of the state just like generators out of the state have contracts to sell into the state," said Borenstein.
In an era of climate change, there needs to be far better planning and the state needs more renewable sources along with other systems to store power for use during peak demand events.