by Planning Engineer
The first week in September of this year California was facing rolling blackouts due to a forecast 20-year high Peak. Residents were asked to cut down electric usage and at risk of rolling blackouts. Is this a new normal? Or can the threat of rolling blackouts be avoided? The likely answer is that the risk of rolling blackouts could be greatly reduced, but because of other priorities such reliability risks are the new normal.
What has peak demand looked like for California in recent history. The Chart below shows recorded peaks and the projected 2022 value that caused concern in early September.
The forecasted peak conditions were 2.5% above the high 20 years ago and 2.9% above what was observed 5 years ago.
The idea that a system might be unprepared because it had a peak that was a few percentage values higher than what was seen 5 years ago would have seemed strange to a planner 30 years ago. Many of us were used to seeing spurts in peak demand growth that averaged 8 to 10% a year or more. The peak demand shown above for California is pretty well bounded. The most basic planning criteria is that a system should be able to survive the loss of the largest generating resource and the most critical transmission element during a peak load with no loss of load and no severe voltage declines or undamped system oscillations. Looking at the variability in load levels here, no particular challenges to planners are apparent. If “green” resources were capable of replacing traditional resources with minor adjustments, we would not see the problems we are seeing.
Why is California challenged now and why might it continue to see challenges in the future? Primarily because the focus on green energy is increasing the percentage of “green” intermittent resources. “Green” resources are not as dependable as traditional rotating machinery nor do they support the system as well. It is likely that these resources have been credited with more ability to provide capacity than is warranted, and when the rubber meets the road they don’t perform as “expected”. Intermittent resources cause problems on both the generation side and the load side. Intermittent solar on the residential side serves to reduce load as seen by the Cal ISO. When solar is not performing well available load which is not displaced by solar on the residential side increases concurrent with solar reduction on the supply side.
If California were more honest about the capabilities of “green” intermittent resources planning would be enhanced. However, being honest about the capabilities of “green” resources would have consequences that some would find unacceptable. There has been a big push to make “green” options appear much more economic and capable than they are so that they will be more competitive. Subsidization of “green” resources by traditional uses occurs in many ways. In addition to crediting “green” resources above their dependable capability, others subsidies include directing costs associated with such additions to others. Being honest makes the “green” dream a much harder sell. Assuming that “green” resources work well saves other investment in the grid. This subterfuge tends to limit the cost increase that should be imposed by these resources, but does so at the cost of reliability. This tradeoff takes a while to see as we have built the electric grids to have very high levels of reliability at the bulk level. In the short term it looks like you are getting a cleaner, equally reliable system at a moderate cost increase. But as penetration levels increase, cost get higher and reliability gets much worse.
In 2015 I wrote here:
Greater penetration of renewable resources will limit the options available to operators while at the same time increasing uncertainty around expected generation patterns. To accommodate such uncertainty the choices are to: 1) increase grid costs and infrastructure, 2) limit the operational flexibility of the grid, 3) increase generation costs through backup generation resources or 4) live with increased risks and degraded reliability. Likely all four are and will continue to occur to some extent as the penetration of intermittent resources increases.
California policy makers have determined resource investment, resource allocations and how and when grid improvements are made to enhance reliability. To blame extreme weather for causing the current concerns seems to be quite a reach. I suspect that a careful and fair examination of the weather data would should that the weather triggering such concerns this was not anything extraordinary considering historical weather patterns. But if it there truly was something unusual about the weather as driven by climate change, shouldn’t this have been anticipated by those responsible? California is spending vast sums of money on the power system based on climate change, it seems incredible that they would not incorporate such anticipated changes into their planning models.
Will California learn to avoid peak rolling blackouts? If reliability were a primary concern, this situation shouldn’t bubble up again in a few years. California should be able to properly credit the ability of its power resources and match them to projected weather ensuring adequate power. If other priorities prevent responsible steps to ensure reliability, then those priorities, not the weather, should claim responsibility for the consequences. If California wants to continue as they have, they should be honest and make statements such as the following:
This is the end of affordable, reliable electric service as we understood it for most of the last 50 years. We are choosing to go with “green “technology to deal with the climate crisis. Keeping past reliability levels will raise your costs tremendously. As we try to put on limit on costs this will decrease your reliability. At time the power will not be there. We’ve all got help each other out.
Of course, once everything is looked at honestly it may lead to further change. Ideally the power system represents the best balance between economics, reliability and public responsibility. California has reached a balance skewed by false expectations that “green” resources cannot meet. Creating a balance that looks at the true costs and reliability impacts of green resources should benefit electric users in California. Hopefully as consumers, voters, policy makers and others better understand the accurate pros and cons of available generating options either consumers will understand why their reliability is poor or else better choices will be made by policy makers on their behalf. Fairly accounting for the performance of system resources will lead to better balance of economics, reliability and costs.
via Watts Up With That?
September 13, 2022 at 04:44PM