NYISO

NYISO settles the state as eleven load zones, A through K, and the map of those zones is the market's whole story. Power is generated cheaply in the north and west (hydro on the Niagara and St. Lawrence, upstate nuclear) and consumed in the southeast, where New York City and Long Island sit behind constrained interfaces and underwater cables. When the paths in fill up, the state splits: upstate prices sag, downstate prices climb, and the spread between zone A and zone J becomes the cleanest congestion signal in the market.

The public record here is unusually explanatory. NYISO doesn't just publish price spreads: its limiting-constraint feeds name the facility, contingency, and constraint cost shaping dispatch in both real time and day-ahead, and five-minute interface flow and transfer-limit data shows the import paths actually filling. Even Lake Erie loop flow (the circulation of power around the lake that quietly reshapes New York's transfer capability) is published as its own series.

Ask the Grid mirrors that depth: zonal and generator-level LBMP with energy, congestion, and loss components, ancillary prices, behind-the-meter solar, implied emission rates, outage schedules, and real-time operator events and messages, all on the same clock.