Based on the Enverus Intelligence® Research Winter Power Market Outlook webinar for ISO-NE and NYISO, presented by Adam Jordan, Director of Power Analytics, and Manas Trivedi, Principal Analyst.
Two new 1.25 GW lines now deliver Québec hydropower into the Northeast, changing where prices clear. NECEC continues to depress Maine prices and widen the north-south basis in ISO-NE. Enverus Intelligence® Research (EIR) expects CHPE to narrow the NYC premium this winter. Add a record El Niño and a warmer-than-average winter, and the biggest risk shifts from cold weather to line availability.
A record El Niño points to a warmer Northeast
EIR’s analog years are 2015/16 and 2023/24, which average +1.6 on the Relative Oceanic Niño Index (RONI). The global climate model statistical average for December through February is +3.1, and the models show record-high El Niño conditions. EIR’s forecast is for a warmer-than-average winter, in both ISO-NE and NYISO.
The analog years show above-average wind in December and January and below-average wind in February. Cold risk remains: the 2023 analog carries it for December, and the 2016 analog carries it for January and February.
ISO-NE: NECEC and a new wave of supply
New England Clean Energy Connect (NECEC) is a 1.25 GW line that delivers hydroelectric power from Québec to Maine. It entered commercial operation in January 2026. NECEC has consistently suppressed Maine prices, and we expect that to continue this winter. It has also widened the Maine-SEMASS spread. EIR forecasts SEMASS to be much lower than last winter, but mainly because of warmer weather and lower heating load, not NECEC.
New generation in ISO-NE focuses on battery storage, solar and offshore wind:
- Revolution Wind (715 MW offshore wind): As of mid-September 2026, all 65 turbines are installed and construction is complete, with full operation expected later this year. During strong offshore wind, it should put downward pressure on Rhode Island and SEMA prices.
- Three Rivers Solar (100 MW): Expected online at the end of 2026 in Hancock County, Maine, adding midday solar that may amplify oversupply and influence flows across the ME:NH interface.
- Taft BESS (200 MW / 800 MWh): A 4-hour battery under construction in West Central Massachusetts that should improve local flexibility and modestly reduce short-duration price spikes.
ISO-NE load growth is minimal, near 0.90% on-peak and 0.78% off-peak year over year in early September.
RGGI keeps adding to heat rates
The Regional Greenhouse Gas Initiative (RGGI) raises the cost of carbon emissions for fossil fuel generators, which lifts heat rates in ISO-NE and NYISO. RGGI allowance prices have more than doubled in three years, from $14.88 per ton in December 2023 to $37.56 per ton by October 2026.
ISO-NE price view: below the forwards
| ISO-NE | Bearish heat rate | Expected heat rate | Bullish heat rate | Forward heat rate | Expected price |
|---|---|---|---|---|---|
| December | 8.1 | 9.6 | 11.7 | 10.5 | $99.76 |
| January | 7.6 | 8.3 | 12.3 | 8.8 | $173.96 |
| February | 7.2 | 8.6 | 12.0 | 8.9 | $151.29 |
EIR’s expected-case heat rates sit below the forwards in all three months. We expect a strong El Niño to keep New England warmer than normal, reducing heating demand and easing natural gas pipeline stress. That should reduce sustained scarcity pricing and reliance on oil-fired generation.
NECEC availability is the main risk. An extended outage would remove Canadian hydro support while Phase II HQ flows remain variable. Lower demand and stronger wind can also raise the risk of ME-NH congestion and negative pricing in Maine.
NYISO: CHPE compresses the NYC premium
Champlain Hudson Power Express (CHPE) is a 1.25 GW line that delivers hydroelectric power from Québec to New York City. It entered commercial operation on June 1, 2026. Its impacts so far:
During extreme cold, reduced Québec exports could tighten NYISO supply and lift NYC prices.
- CHPE imports lower Zone J prices.
- CHPE strongly compresses the NYC-West (J/A) basis.
- CHPE doesn’t relieve local Long Island constraints, so Long Island-NYC spreads remain driven by Zone K fundamentals.
New NYISO supply lands mostly upstate. Cider Solar (557 MW) in Genesee County, expected at commercial operation at the end of October 2026, is likely to widen the basis between upstate and NYC and Long Island prices. Excelsior Energy Center (280 MW solar) and the roughly 340 MW Alle-Catt Wind Farm follow in November and December 2026. Meanwhile, NYISO load is down, with year-over-year load in early October 2026 down 1.95% on-peak and 2.01% off-peak.
NYISO zonal implied heat rates rose from 2021 to 2026. Capacity retirements tightened the local market, local congestion kept zonal prices high, carbon and regulatory costs added a premium, and low gas prices lifted heat rates.
NYISO price view: Zone J above the forwards
| NYISO Zone J | Bearish heat rate | Expected heat rate | Bullish heat rate | Forward heat rate | Expected price |
|---|---|---|---|---|---|
| December | 13.5 | 15.2 | 16.6 | 14.3 | $101.05 |
| January | 11.9 | 14.9 | 16.8 | 14.2 | $165.26 |
| February | 11.9 | 14.8 | 16.2 | 14.3 | $147.52 |
In contrast to ISO-NE, EIR’s expected-case Zone J heat rates sit above the forwards in all three months. We expect warmer-than-normal weather to reduce heating demand and limit congestion risk, and below-average demand should help contain the NYC-West basis. Periods of strong wind, however, could drive larger west-to-east flows and widen regional price spreads.
CHPE availability is the primary market risk, because a prolonged outage during a cold spell could sharply increase NYC congestion.
What to take into the winter
- EIR expects a warmer-than-average winter with El Niño in ISO-NE and NYISO from December through February.
- NECEC continues to depress Maine clearing prices and widen the north-south basis in ISO-NE.
- CHPE’s peak-hour dispatch is expected to narrow the Zone J premium and compress the J-K spread this winter.
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About Enverus Intelligence® | Research, Inc. (EIR)
Enverus Intelligence® | Research, Inc. (EIR) is a subsidiary of Enverus that publishes energy-sector research focused on the oil, natural gas, power and renewable industries. EIR publishes reports including asset and company valuations, resource assessments, technical evaluations, and macroeconomic forecasts and helps make intelligent connections for energy industry participants, service companies, and capital providers worldwide. See additional disclosures here.
