← ALL INSIGHTS
Market Intelligence · September 21, 2026

ERCOT battery revenue didn't just fall after RTC+B. It got unpredictable

Monthly storage revenue now swings by a factor of almost three, and ancillary services is the bigger loss.

We've been watching ERCOT's battery storage revenue since real-time co-optimization (RTC+B) launched in December, and the story in the data isn't the one most people are repeating.

ERCOT battery revenue didn't just fall after RTC+B. It got unpredictable — Altakon chart
Altakon analysis. Sources listed below.

Average ERCOT battery revenue was $2.00/kW-month in October and $2.38 in November. Then RTC+B launched, and December dropped to $1.70. February fell further, to $1.16. March recovered to $1.88. April jumped to $3.12. That's not a steady decline. It's revenue that has become far less predictable from one month to the next.

Look closer and you can see why. In March, ancillary-services revenue fell $0.52/kW year-over-year, almost twice the $0.27/kW drop in real-time energy revenue. Ancillary services isn't just a shrinking piece of the pie anymore. It's the bigger dollar loss, and the harder one to plan around.

For anyone operating or financing storage assets in this market, that changes the underwriting conversation. A flat revenue forecast doesn't survive contact with this data. The real work now is building an operating and hedging strategy around volatility. This is the kind of volatility Altakon builds revenue and operating strategy around.

Sources

  • Modo Energy ERCOT BESS benchmark reports (October 2025 – April 2026).

What are you trying to build in the U.S.?