[Market Monitor] ISO-NE Ancillary Service Costs Continue to Rise: DASI Explained

Zach Reynolds

Ancillary services, critical functions that keep the electric grid stable, became more volatile and costly in 2025 following ISO-NE’s Day-Ahead Ancillary Services Initiative (DASI), which shifted procurement closer to real time. While this improves alignment with system needs, it also increases customer exposure during extreme weather, tight supply conditions, and other system stress events.

We cover these developments in our latest Market Monitor.

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In this explainer video, we cover:

Why ancillary costs are now more closely tied to fuel prices, generator availability, and demand volatility.
How events like Winter Storm Fern have amplified cost impacts under DASI
What this means for customers on fixed-priced contracts, where certain ancillary charges may still be passed through.

To learn more or submit questions, contact a Tradition Energy advisor.

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