With the renewable-dominant energy grid for Spain and Portugal now down, bringing the nations to a halt, many now wonder whether California’s grid could face similar outages in the future. Experts say the state’s renewable energy policies could produce a 21.2% power shortfall by 2045, putting Californians’ energy and economic security at risk.

While details remain unclear as of the time of publication, grid operator Rede Eletrica Nacional says a “rare atmospheric phenomenon” caused temperature variations, which in turn “caused synchronisation failures between the electrical systems, leading to successive disturbances across the interconnected European network.”

Bloomberg energy expert Javier Blas pointed out that Europe’s transition from turbine-powered energy — such as that produced by nuclear, fossil fuel, and hydropower plants — leave the systems unable to compensate for the sudden change, and result in poor grid reliability and resilience.

“The extreme volatility means not only pain for consumers, but also difficult investment decisions by producers,” said Blas. “Renewable energy — and the need for costly gas-fired power plants as backup during bad weather periods — are the main reason behind that volatility.”

A report from the federal National Renewable Energy Laboratory suggests that turbine-powered plants provide inertia — the continued movement of turbines for several seconds even after an interruption — “allows the mechanical systems that control most power plants time to detect and respond to the failure,” — and that the loss of such systems could impact reliability if mitigation efforts are not taken.

“As the grid evolves with increasing penetrations of inverter-based resources — e.g., wind, solar photovoltaics, and battery storage — that do not inherently provide inertia, questions have emerged about the need for inertia and its role in the future grid,” wrote NREL in a report.

NREL also noted that it nonetheless is possible to “quickly detect frequency deviations and respond to system imbalances” with a renewable-powered system, citing innovations in Texas’s power grid, which has surpassed California as the nation’s renewable energy leader.

"Before the outage hit, Spain was running its grid with very little dispatchable spinning generation," noted Blas on X.

A new report from the Pacific Research Institute suggests that California may one day have similar challenges in maintaining energy reliability, estimating the state’s requirement that energy be 100% will result in a 21.2% energy shortfall by 2045, and higher costs for Californians.

“Consumers will be forced to cover the costs of the new alternative energy investments as well as those for removing existing infrastructure,” wrote study authors Kerry Jackson and Wayne Winegarden. “Consequently, they will be paying the costs of two repetitive energy systems – the new ‘green’ energy generation framework and the prematurely disfavored generation facilities.”

Jackson and Winegarden estimate combined costs will reach between $231.7 billion and $268.7 billion, or between $17,398 and $20,182 per household, to fund the continued transition — and don’t include the cost of falling grid reliability.

“Alternative energy resources, despite tremendous advancements, still face significant limitations that include a more costly and less reliable generation infrastructure,” warned Jackson and Winegarden. “These higher prices and reduced reliability also impose an economic cost.”

According to the Energy Information Energy, California residential energy cost $31.7 cents per kilowatt-hour, or nearly double the national average of $16.4 cents per kilowatt-hour. Energy rates in California have doubled in the last decade alone.