Today’s LiveWire Spotlight reviews a joint report issued by NERC and WECC analyzing four 2021 incidents in CAISO where an unwarranted number of solar photovoltaic (PV) facilities failed to ride through routine transmission line Faults.  The report identifies eight causes that make up 86.8% of the total MW losses over the four events – all of which have been seen in previous outages thoroughly studied by NERC and WECC in the past.  It goes on to offer over a dozen recommendations to deal with the issues – all of which call for mandatory measures to be imposed (i.e.; NERC standards, ISO rules, and pro forma interconnect agreements.

The root cause analysis of multiple solar PV disturbances in CAISO performed by the NERC-WECC joint team is comprehensive and accurate.  Its conclusions are less well grounded in data – in fact, they seem to show that voluntary measures are returning excellent results.