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Welcome to New ISO Blog

By Elliot Mainzer, President and Chief Executive Officer
June 2021


With summer almost here, it is my pleasure to welcome you to our new blog, Energy Matters, which debuts in this space today.

In regular postings, I and others at the California Independent System Operator will share stories about the work we do and steps we take—with our partners and stakeholders—to keep electricity in California flowing safely, reliably, and efficiently as our state transitions to a carbon-free electricity future.

We are always busy at CAISO, but summer is our most challenging season. From June through September, California’s hot weather puts the greatest strain on the electric grid, primarily from our heavy reliance on air conditioning.

That reality was driven home last August when a record heat wave engulfed the Western United States and we did not have access to all the electricity needed to meet demand.

Typically, when conditions require additional electricity in California, we can import it from our regional partners. But with the entire West sweltering last August, other states needed that electricity for their own consumers. Our options were further limited because prolonged dry conditions left us with less hydroelectric power than normal.

With supplies tight and demand extra high, we can take emergency steps that include requiring additional generators to start their power plants, request utilities to implement demand-response programs that encourage consumers to use less electricity, or issue Flex Alerts that appeal directly to the public to voluntarily conserve.

As a last resort, we may also employ controlled brief power shutoffs, otherwise known as rolling outages, to avoid an uncontrolled, cascading outage across a wider geographic area. Rolling outages are not something any grid operator wants, and at CAISO we are 100 percent focused on doing everything we can so we’re not in that position again this summer.

A few weeks ago, I talked about our summer readiness at a legislative hearing with colleagues from the California Public Utilities Commission and the California Energy Commission. We shared some of the collaborative actions we’ve taken since last summer’s rolling outages, including added capacity and relieving some of the pressure points that manifested themselves during the August 2020 heat wave. We have also been revising and improving our communications protocols so the public gets plenty of advance notice of a likely extreme weather event and all the information it needs to get through it.

As I told legislators and our recently released annual Summer Assessment underscored, these collective actions leave electricity supply conditions in better shape for this summer than a year ago.

But as we also cautioned, the power grid is still susceptible to stress during extreme heat waves that extend across the West. Imported energy could again be limited. With another extreme weather event, it is possible we would once more need to impose emergency conditions that could include rotating outages. We would also call again on Californians to voluntarily conserve, as they did so well last year, when we issued our Flex Alerts.

As California continues to advance policies that combat climate change, we could not be more pleased that so many of our peers and partners across the West are pushing similar goals and initiatives. Through continued collaboration with other like-minded entities and by bringing in more new partners, we have the best chance of achieving a clean, safe and reliable energy future for us all.

Thank you for reading our debut blog post. I hope you make it a habit to check back often for useful information and insights into the work we do.

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