Batteries in SPP South had the potential to earn $9.96/kW-month in June 2026, or roughly $119/kW-year annualized.

That was down from $12.20/kW-month in May 2026.

A battery operating with perfect foresight at the South Hub earned 78.6% of its revenue from Regulation. Day-ahead Regulation Up cleared at $12.35/MW, the RTO's highest-priced ancillary service.

RTO West continues to show the highest revenue potential, out-earning both the South and the North. That lead came almost entirely from Ancillary Services, where the West cleared higher in both Regulation Down and Spinning Reserves.

But that opportunity is shallow. SPP West is a thin market with low generation and load. Higher clearing prices reflect an early, lightly contested market rather than a deep revenue pool. Most operating batteries in SPP today sit in the South.

The remainder of this analysis breaks down what drove the revenue opportunity for battery storage in SPP in June 2026.

To learn about the price spreads at the launch of RTO West, read last month's May 2026 SPP benchmark report.

Regulation provided 78% of simulated revenues in June 2026

Ancillary Services provided 80% of modeled revenue in June, with Regulation alone making up 78% of the total.

Day-ahead Regulation Up prices cleared at an average of $12.35/MW in June, up 1.8% year-over-year - the highest-priced product in the stack. This service allows the system operator to make up for shortfalls in its dominant wind production. The high payments reflects of flexible gas, coal and hydro to cure short-term imbalances.

Day-ahead Spinning Reserve fell 22% to $3.8/MW, and day-ahead Ramp Up dropped 38.9%.

Read our guide to SPP’s Ancillary Services to learn more about how batteries participate in each market.

Day-Ahead TB4 spreads in SPP South fell to $4.7/kW

Day-ahead TB4 price spreads measure the value of cycling a battery between the four highest- and lowest-priced hours in a day.

Across June, a four-hour battery performing a single cycle a day with perfect foresight earned $4.75/kW-month in SPP South, down 11.2% year-over-year. SPP North totaled $4.42/kW-month, easing 1.8%, while SPP West totaled $3.66/kW-month.