May 2026 day-ahead and real-time TB4 spreads rose year-over-year across every NYISO zone

Average daily TB4 spread by NYISO zone, May ($/MW-day)

Day-Ahead

Real-Time

Source: NYISO, Modo Energy

Note: TB4 spread calculated as the difference between the 4 highest and 4 lowest price hours in each day.

MODOENERGY