Thanks for starting this thread,
@getakey!
CAISO released their absolutely maddening Root Cause Analysis (RCA) for the August 2020 outages
http://www.caiso.com/Documents/Preliminary-Root-Cause-Analysis-Rotating-Outages-August-2020.pdf.
It's a long and mostly political (which is unfortunate) document that blames 1) climate change induced "extreme heat storm", 2) the renewable production issues that
@getakey mentions above, and 3) energy marketplace practices that exacerbated supply challenges.
I found it a fascinating read but am calling it absolutely maddening because:
a) While the heat wave is a considerable factor there's no conversation about how the
peak demand for the 2 days of the rolling outages of 47GW was lower than the peak demand of
50GW in 2017. Unless those are not apples-to-apples comparisons (which they may be if CAISO service areas changed) that's a huge gap to explain and certainly isn't "unprecedented" or "extreme" demand. It speaks to how CA has done a poor job managing capacity and spinning reserves in its transition to renewables (which have no capacity planning or spinning reserves!). Blaming climate change for these outages as the first reason seems like a convenient political scapegoat and doesn't pass the smell test.
b) The document says explicitly "The existing resource planning processes are not designed to fully address an extreme heat storm like the one experienced in mid-August" which is
contradicted by their own May 20, 2020 report which states "The CAISO 2020 1-in-5 and 1-in-10 peak demand forecast are 47,775 MW and 48,457 MW" (page 3,
Peak Demand Forecast). Worse, they say it in the 3rd paragraph of the executive summary! "However, if a heat wave occurs that impacts a broader area than the CAISO, the availability of surplus energy to import into the CAISO could be diminished." They absolutely knew it was possible (and even likely!) by their own analysis not 3 months before the outages but simply didn't plan for it.
c) There is no reference in the letter to Newsom about how the policies he implemented in response to COVID19 directly contributed to the outages. It's lightly discussed later in the RCA and there is even an
entire analysis done by CAISO back in July which clearly shows that due to the Governor's COVID19 policies there is a net increase in demand during the summer months between 18:00 and 5:00, the peak demand time and also the time where little to no solar generation happens. While a few % change may seem inconsequential 1.05% of the load was shed during the stage 3 outages on each of those days (500MW shed out of a total demand of 47GW).
d) It's buried in the document and never called out as a specific reason but one of the major factors for the August 15, 2020 outage was the fact that CAISO erroneously told Panoche to decrease generation by 250MW! (
page 37). Had this not happened likely the Stage 3 emergency would never had been declared thanks to a substantial increase (+500MW) in wind production 30 minutes later. The fact that they did not admit such a glaring error up front indicates that they haven't been up front about all of the systemic problems.