Week-by-Week March 2026 LMP Breakdown
March 2–5: $73.22/MWh DA, $85.68/MWh RT
The month opened with elevated prices driven by binding reserve constraints and high fuel prices. Real-Time LMPs exceeded $170/MWh on March 2 as ISO-NE dispatched oil-fired generators to supplement tight gas supply. Peak load hit 17,774 MW on March 3 — well above typical March levels.
March 9–12: $34.76/MWh DA, $36.28/MWh RT
A sharp reversal brought prices to spring-transition levels. Milder weather reduced heating demand and eased gas constraints. However, even this “calm” week saw RT spikes above $105/MWh on March 12 when actual loads exceeded day-ahead forecasts.
March 16–19: $50.04/MWh DA, $59.06/MWh RT
The third week ratcheted prices back up. RT LMPs surpassed $195/MWh on March 19 — the highest intra-day spike of March — driven by loads once again exceeding forecasts. The 18% gap between DA ($50) and RT ($59) averages signals persistent forecast uncertainty in the ISO-NE system.
Why March Volatility Matters After a $6B Winter
January 2026 set the highest ISO-NE wholesale prices since 2014. The full Winter 2025/2026 totaled approximately $6 billion in wholesale energy costs — the most expensive winter in market history. March’s continued volatility demonstrates that:
- Winter patterns persist into spring: Gas pipeline constraints and load forecast errors continue to drive RT spikes well into the shoulder season
- DASI amplification: The Day-Ahead Ancillary Services Initiative co-optimization magnifies price coupling when reserves tighten, contributing to the $195/MWh spike
- Oil-gas fuel switching: Oil-fired generators were dispatched during Week 1 when gas prices were elevated, adding cost premium to the energy clearing price
What This Means for Commercial Buyers
- Real-time exposure risk: Buyers on indexed or spot-market pass-through contracts are absorbing these spikes directly. The $170–$195/MWh RT spikes translate to 17–19.5¢/kWh in those hours — 2–3× normal rates.
- Fixed-rate contract value: The volatility reinforces the value of fixed-rate supply contracts for the upcoming 2026/2027 capacity year (starting June). Lock-in before PJM-style capacity cost passthrough hits ISO-NE rates.
- Demand response opportunity: Every RT spike above $100/MWh represents potential DR revenue. Facilities that can curtail 500+ kW during these events should evaluate ISO-NE demand response participation.
- Budget planning: Use the March DA average of ~$52/MWh as a planning benchmark, but model 15–20% upside for RT volatility exposure through at least May 2026.
- Watch DASI reform timeline: ISO-NE’s planned FERC filing for DASI reforms (expected summer 2026) could reduce ancillary cost amplification if approved.
Source: ISO New England Mid-Week Market Updates (March 2–5, 9–12, 16–19, 2026); ISO-NE Market Data; EIA; ISO Newswire.