One afternoon defined July BESS revenues in ISO-NE. On July 2, system demand peaked at 25 GW and day-ahead prices at the Internal Hub averaged $299/MWh. All three day-ahead reserve products averaged $241/MWh on July 2. This was 11 times the monthly mean and, in many hours, these reserve products clear near zero.

Modo Energy's virtual BESS benchmarks reflect that concentration. A BESS in Boston could have earned $4,772/MW-day on July 2 alone, a third of its monthly revenue. In total, the top four days produced 59% of July BESS revenue in Boston. In July, a benchmark BESS earned 60% of its revenue in Boston and 73% in Maine by holding day-ahead 10-minute non-spinning reserve positions.

Real-time spreads, however, decreased 13% year over year at the Internal Hub to $231/MW-day. This extends the compression Modo Energy reported in June, though the day-ahead spread stayed the second-highest of the past year.

Key takeaways

• A BESS in Boston or Maine could have earned $14.5/kW-month in July ($466/MW-day and $468/MW-day respectively). Day-ahead 10-minute non-spinning reserve contributed 60% and 73% of the totals.
• July 2 delivered a third of the month's revenue in both zones. Demand peaked at 25 GW, 2% above the July 2025 peak, and day-ahead reserves cleared at $241/MWh against a $22/MWh monthly average.
• The Internal Hub real-time TB4 spread fell 13% year over year to $231/MW-day, and the day-ahead TB4 spread fell 14% to $316/MW-day, still the second-highest of the past year.
• Wind generation rose 85% year over year to a 612 MW average while natural gas fell 18% to 8.2 GW, with average demand down 7%.
• Vermont led the zone ranking on real-time TB4 spreads at $250/MW-day, with Maine at the bottom at $219/MW-day.

One day delivered a third of ISO-NE benchmark revenue for July

Modo Energy's virtual BESS (vBESS) benchmarks simulate the revenue available to a battery energy storage system dispatching against market prices. In July, a BESS in Boston or Maine could have earned $14.5/kW-month, within 1% of each other. The revenue mix sets ISO-NE apart from MISO, where day-ahead energy leads the stack. Here, day-ahead 10-minute non-spinning reserve was the largest single revenue line.