CAISO

CAISO's defining physics is the daily solar cycle. Utility-scale solar floods the middle of the day, hollowing out net load, and then exits within a couple of hours of sunset, right as demand peaks. That evening ramp sets the tempo for everything else: when batteries charge and discharge, when gas is called, when imports matter, and when prices spike. It is also why CAISO publishes an unusually clean storage series: five-minute net battery output for the whole footprint, positive discharging, negative charging.

The market itself is nodal and component-split. CAISO prices carry explicit energy, congestion, and loss components at every pricing node, in both the day-ahead market and 15-minute real-time pre-dispatch, so a price separation can actually be decomposed rather than guessed at. Constraint evidence is public too: five-minute shadow prices on interties show when import and export paths to neighboring balancing areas bind and in which direction, and nomogram shadow prices flag the multi-element stability limits that single-line views miss.

Beyond its own borders, CAISO operates the Western Energy Imbalance Market, which extends its real-time dispatch across much of the West. That makes the tie constraints and border prices in this data the visible seam between California and everyone it trades with.