In sun-soaked California, suburban homes with solar panels have become familiar, symbolizing the state’s clean energy ambitions. But this green push has brought an unexpected twist: sometimes California churns out more solar energy than it can use, leading to significant waste of this clean power.
The “duck curve” quirk shows the mismatch between peak solar output and energy demand. The “duck’s belly” marks times when solar production outstrips demand, usually when electricity needs are low on bright spring days. Elliot Mainzer, CEO of California’s Independent System Operator (CAISO), which manages 80% of the state’s electricity, sheds light on the issue.
“We experience periods, particularly in the spring, where electricity demand is low, and solar production is high, resulting in surplus energy that California can’t fully utilize,” said Mainzer. “In such cases, we leverage our transmission connections to export excess energy to other Western states. However, under extreme conditions, we have to curtail, or turn off, some solar production.”
This curtailment has led to a massive waste of renewable energy. CAISO data shows nearly 2.6 million megawatt-hours of renewable energy have gone to waste this year, enough to power every home in San Francisco for a year. The problem gets worse with “congestion,” where transmission lines can’t handle the electricity load being produced.
Mainzer advocates for expanding the state’s transmission infrastructure to mitigate these issues. “Building new transmission lines is crucial for accessing and delivering power from new solar projects, batteries, wind farms, and geothermal resources to consumers. Without these lines, the generated energy remains stranded.”
Governor Gavin Newsom’s team is pushing for more battery storage solutions to stash surplus power for peak times and tackle the extra energy. But this plan has stirred up some controversy. The California Public Utilities Commission (CPUC) has slashed financial incentives for homeowners putting up solar panels, a move that’s hit the rooftop solar industry hard.
Ed Murray, President of the California Solar and Storage Association and operator of Aztec Solar, has felt the effects firsthand. “The changes in incentives have been devastating. We’ve seen a significant drop in sales, leading to layoffs and a struggle to remain cost-effective,” Murray said. “The new rules make it necessary for homeowners to install costly battery systems, which many can’t afford.”
The fallout from these policy changes shows up clearly in the numbers. Residential solar installations nosedived by 66% in the first quarter of 2024 compared to the same stretch in 2022. The California Solar and Storage Association figures that 17,000 green jobs have vanished across the state since the shifts in the incentive structure, called net metering.
Governor Newsom defends the state’s approach, emphasizing the significant progress in solar energy production. “California is a leader in solar energy, producing nearly twenty times more solar power than a decade ago. We are rapidly adding batteries to capture excess energy for use at night,” Newsom stated.
Supporters of the revised incentives argue that the shift is necessary to address equity concerns, as the previous net metering system increased energy costs for non-solar customers. CPUC member John Reynolds highlighted this issue, stating that while net metering brought solar to many Californians, it also imposed high costs on non-solar customers, necessitating reform.
Despite these challenges, Murray remains hopeful but cautious. “California’s leadership in solar energy sets a precedent for other states. Changes here can influence policies nationwide,” he noted. “We need rooftop solar to achieve our clean energy goals, including supporting electric vehicles and energy-efficient appliances. Without it, the transition to a renewable future becomes much harder.”
As California strives towards its 100% clean energy goal by 2045, navigating these new challenges will ensure a sustainable and equitable energy future.
