The California Independent System Operator (Cal-ISO) is proposting changes to its day-ahead market, including moving from hourly to 15-minute increments. The changes will allow Cal-Iso to extend its day-ahead market function to the participants in the Western Energy Imbalance market.
Read more here:
https://www.platts.com/latest-news/electric-power/houston/california-iso-eyes-changes-to-day-ahead-market-10270437