ERCOT and PJM Gas-Power Demand Offsets CAISO Collapse as US Grid Mix Diverges
Regional electricity market divergence is reshaping natural gas burn patterns, with ERCOT and PJM absorbing growth that CAISO's solar buildout is rapidly displacing.
Henry Hub NYMEX front-month natural gas traded at $3.01 per million British thermal units on July 9, 2026, holding near levels that have attracted renewed investor attention to the gas-to-power story — but the national figure obscures a stark regional divergence that is increasingly defining how US power demand translates into gas burn.1
PJM Western Hub spot power reached $72.38 per megawatt hour on July 9, 2026, a level consistent with active gas dispatch in the mid-Atlantic and Great Lakes region. ERCOT, the Texas grid, has been absorbing rapid demand growth from cryptocurrency mining, data centre build-out, and oil and gas field electrification — factors that together are sustaining natural gas-fired generation even as solar capacity expands inside the grid.5
The EIA's May Short-Term Energy Outlook forecast US electric power sector gas consumption averaging 43.7 billion cubic feet per day during the summer of 2026 — flat versus the summer of 2025 despite a 2% increase in overall US electricity demand, because incremental renewables are absorbing most of that demand growth nationally. Within that flat aggregate, however, the composition is shifting: ERCOT and PJM are doing the heavy lifting on gas while CAISO's solar and wind buildout is compressing gas burn in California to the point where it is effectively running in reverse as a gas demand driver.5
CAISO NP15 spot power stood at $28.50 and SP15 at $23.79 on July 9, 2026, prices that reflect abundant solar generation suppressing midday clearing prices well below the levels at which gas peakers are economic in the California market. The Edison Electric Institute reported US electricity generation up 2.2% year-on-year in its latest weekly reading as of mid-May 2026, and total generation over the prior year ran 1.8% higher — but CAISO's contribution to gas demand is diminishing structurally as each new gigawatt of in-state solar reduces the hours in which gas-fired capacity sets the price.2
In New York, the ISO-NE Mass Hub spot price reached $52.00 on July 9, 2026, partly reflecting structural constraints on gas pipeline capacity into New England — a vulnerability that Enbridge moved to address when it launched an open season during the week of May 18 (2026-05-18) to explore an expansion of its Algonquin natural gas transmission system serving demand in that region.3
The MISO Indiana Hub spot cleared at $85.00 on July 9, 2026, a figure that reflects coal's continued role in the central US dispatch stack. Through the first four months of 2026, the Midcontinent Independent System Operator's dark spread — the margin between coal generation costs and wholesale electricity prices — remained favourable for coal-fired generation, according to EIA data published on May 20 (2026-05-20). Coal retained an economic foothold in MISO even as it retreated in ERCOT, where EIA forecast solar generation to exceed coal output for the first time on an annual basis in 2026, with solar projected at 78 billion kilowatt-hours against coal's 60 billion kilowatt-hours.4
The structural story is one of hardening regional differentiation in the US gas-to-power market. ERCOT remains the growth engine: data centres are consuming an increasing share of generation, and EIA projects no new coal plant construction in the grid while gas remains dominant at roughly 44% of the generation mix. PJM's industrial base and legacy fuel mix keep gas dispatch elevated. CAISO, meanwhile, is reordering its merit stack — gas-fired power is increasingly a residual provider that clears only in the hours solar cannot cover.5
For traders positioning in NYMEX Henry Hub front-month gas, the demand signal from ERCOT and PJM is the more reliable leading indicator than the national aggregate. CAISO's demand destruction of gas is a structural shift, not a cyclical one, driven by a solar capacity build that accounted for approximately 40% of all US utility-scale solar additions in 2026 occurring inside Texas alone.
What to watch: EIA storage data and any escalation or further de-escalation of the US-Iran situation, which continues to influence global LNG flows and therefore the export-demand component of Henry Hub pricing. Qatar's Ras Laffan facility was still running at reduced capacity after damage earlier this year took out roughly 20% of global LNG supply, and weekly LNG vessel departures of 141 billion cubic feet during the week of May 11 (2026-05-11) signalled that US export infrastructure was absorbing some of the slack.2