California ISO Urges Electricity Conservation

Midsummer’s Day is a few days away, and on the west coast of the United States things are heating up. Here is the surface temperature map for the western USA yesterday afternoon:

Those sort of temperatures mean that lots of air conditioning units are working hard, and consequently the California Independent System Operator (CAISO for short) called for a voluntary “Flex Alert” yesterday, in order to persuade its customers to voluntarily reduce electricity demand:

The desired aim seems to have been achieved, with the evening demand peak having been “shaved” somewhat, and with last year’s rolling blackouts averted so far in 2021:

Here’s how the differing sources of electricity supply coped:

Here’s an expanded view of the contribution of the ever expanding amount Californian battery storage to electricity supply during the evening demand peak:

The California heat wave is forecast to continue today, as is another high peak in demand:

And so:

According to the California ISO news release:

Consumers are asked to conserve energy tonight and tomorrow evening by:

  • Setting thermostats to 78 degrees or higher, if health permits
  • Avoiding using major appliances
  • Turning off all unnecessary lights Consumers are also encouraged to use fans for cooling, and to unplug unused electrical items.

To be as comfortable as possible during the Flex Alert hours, consumers can take these steps earlier in the day:

  • Pre-cool your home by lowering the thermostat
  • Use major appliances, like your dishwasher, and clothes washer and dryer
  • Close window coverings to keep your home or apartment cool
  • Charge electronic devices
  • Charge electric vehicles

The ISO is continuing to monitor weather and grid conditions and will have additional announcements as information becomes available.

California ISO Anticipates Another Weekend Heatwave

Following the recent series of rolling blackouts in California, we got wind of this a couple of day ago via Twitter:

Our suspicions have since been confirmed:


Here is the current GFS forecast for 00:00 UTC on Sunday:

And here is CAISO’s forecast demand for today:

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Bad Weather Batters Global Electricity Grids

Over on the eastern side of the Pacific Ocean there has been a summer heat wave in California:


As a consequence air conditioning works hard, electricity demand goes up, and over the last few days there have been some rolling blackouts across the Golden State. According to the New York Times on August 16th:

As temperatures began to rise in California on Friday and again on Saturday, the manager of much of the state’s electric grid called on utilities to cut power to hundreds of thousands of customers.
But the rolling blackouts on those days left some of the state’s energy experts bewildered. They said that the utilities had plenty of power available and that the blackouts weren’t necessary. The grid’s capacity may be tested in coming days as temperatures are forecast to reach into the triple digits again in some places.

The grid’s capacity was indeed tested in the following days. It’s not clear why the California Independent System Operator (CAISO for short) didn’t issue a call for a voluntary “Flex Alert” on August 15th, but the ultimate consequence was some power cuts. Here’s CAISO’s record of electricity demand and renewable generation that day:

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