How California Can Avoid Throwing Away Solar Energy

By Pacific Southwest Region from Sacramento, US (Solar Panels at Topaz Solar 1) [CC BY 2.0 (http://creativecommons.org/licenses/by/2.0) or Public domain], via Wikimedia Commons

Why would anyone even consider shutting down as much as 80 percent of California’s giant solar power plants, which cost virtually nothing to run and emit no pollution? They also have enough capacity at any given minute to power up more than 7 million households, and solar power is crucial to meeting our renewable energy goals of 33 percent by 2020 and half by 2030. Yet the operator for most of the California grid is already experiencing conditions where it must throttle down down units on sunny afternoons and warns of much more to come.

The California Independent System Operator (CAISO) isn’t anti-solar; turning off renewable generation is a last resort. The problem is that during an increasing number of hours there isn’t enough electricity demand within the state to absorb all our renewable energy production, which includes significant quantities of wind, geothermal, and hydropower in addition to solar. But there’s plenty of demand elsewhere in the West, all of which is interconnected with transmission lines; why not just sell California’s excess clean, renewable power to our neighbors? The western grid as a whole has more than three times California’s power needs, and tens of thousands of megawatts of polluting fossil power generation, all of which costs substantially more to run than California’s solar plants and could be replaced by that solar energy that’s being thrown away in our state.

Unfortunately it’s not that simple. The West is interconnected, yes, but the transmission system is riddled with inefficiencies and market barriers as a result of decisions long ago to create 38 separate “balancing authorities” to manage various parts of the grid across hundreds of thousands of square miles.

Without better integration of the western grid, California’s renewable energy is too often blocked from willing buyers outside the state, and the problem is getting steadily worse. Soon as much as 6,000 to 8,000 of California’s 10,000 megawatts of large-scare solar generation may be curtailed during some hours of this year (and at average wholesale power prices, 6,000 Megawatts could earn more than $200,000 for just an hour’s worth of production). The solution lies in a transition to a fully integrated western grid in which the balancing authorities are consolidated and all generators have full competitive access to electricity buyers across 15 states, two Canadian provinces, and parts of Mexico. For more on this, see my colleague Carl Zichella’s blog.

In the words of Stanford’s Professor Jim Sweeney, an expert on all matters electrical, in a recent op-ed:

By integrating our western power grid—including the Pacific Northwest, the Southwest and California, as well as western Canada and Mexico—we could reduce greenhouse gas emissions and energy costs for consumers, while increasing reliability. This integration would allow in-state wind and solar plants—that often lack timely access to customers elsewhere in the West—to operate at full capacity. In turn, clean electricity would become less expensive, allowing for more development of wind and solar power plants, rather than those relying on fossil fuels.

An essential first step toward western grid integration is action by the California Legislature authorizing the transition, allowing the California Independent System Operator to establish an independent governing board and offer its services to the entire West, so that any utility or generator could join. Governor Jerry Brown has said he remains committed to grid integration and the legislature has been looking into it for almost two years. Action is needed before much more cheap renewable power is thrown away.

About the Authors

Ralph Cavanagh

Energy Co-Director, Climate & Clean Energy Program

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