How a battery earns in Texas (ERCOT)

ERCOT is an energy-only market with no capacity market — batteries earn purely from energy and ancillary services, and from scarcity pricing that can spike real-time offers up to the $5,000/MWh offer cap (cut from $9,000 by the Texas PUCT after the 2021 freeze). Texas is the largest and fastest-growing US battery market, entering 2026 near 14 GW of installed BESS and around 16 GW by May 2026, roughly double a year earlier. A booming solar duck curve — wind and solar met about 37% of 2025 generation, with solar overtaking coal as the third-largest source — creates the cheap-midday, expensive-evening spread batteries live on; energy arbitrage reached about 76% of ERCOT BESS revenue in 2025. Live day-ahead prices are being integrated to quantify the spread.

~16GW

Installed BESS — #1 US market (May 2026)

5,000$/MWh

Offer cap — energy-only, no capacity market

37%

Wind + solar share of 2025 ERCOT generation