Batteries in SPP South had the potential to earn $10.9/kW-month in October 2026, or roughly $131/kW-year annualized. That was 11% below September's $12.3/kW-month.

Around the market, October's best days came during a warm spell early in the month. Oklahoma City's highs ran 9°F to 17°F above normal every day from October 6 to 13. That window held the month's widest spreads and highest revenue days.

​In our September report, we discussed SPP’s request for an interim Resource Adequacy charge imposed on utilities without enough capacity contracted to meet their load this winter. This was following a series of repeated Resource Advisories in SPP West since launch, owing to about half of the region’s capacity being unavailable to the market from April to August.

On October 23, FERC staff found SPP's West market adequacy filing deficient and asked for more information within 30 days, past the proposed November 11 start.

If you have any questions about our SPP research, please reach out to ovais@modoenergy.com.

Day-ahead TB4 spreads widened year-over-year at both eastern hubs

Day-ahead TB4 spreads reached $6.8/kW-month at the North Hub and $6.5/kW-month at the South Hub in October. SPP West cleared $5.3/kW-month.

Spreads continued to decline at both SPP East hubs from their summer highs as the RTO exits the summer. Both peaked at $9.8/kW-month, the North in July and the South in August.