DAM System Lambda

ERCOT's hourly day-ahead system lambda, the system-wide marginal energy component in the cleared Day-Ahead Market.

Prices data ERCOT market

Query with the agent Open on map

Native record

day-ahead delivery hour

hourly (DAM) publication cadence

Evidence

Cleared day-ahead market

A market outcome, not a physical observation

In Ask the Grid

Price nodes on the ERCOT map

Reference for the live grid surface

Overview

For the same delivery hour and settlement point, day-ahead SPP minus DAM system lambda is the point's cleared day-ahead congestion component. Paired with SCED system lambda and real-time LMP, it supports day-ahead-versus-real-time congestion basis by point. It does not identify a binding constraint's effect on a point without direct attribution evidence.

Query contract

Preserve one cleared DAM system-lambda value per delivery hour before joining it to the matching settlement-point price.

Analysis rules

Align settlement-point price and DAM system lambda to the same delivery hour before subtracting.
Compute cleared day-ahead congestion = SPP - DAM system_lambda at point-hour grain before comparing it with real-time congestion.

Interpretation

Day-ahead system lambda is a cleared market result, not a price forecast.
A point congestion component does not identify the binding constraint that produced it without matched shift-factor or direct attribution evidence.

Access

Query from your own tools

Use the guarded HTTP endpoint directly, or connect an MCP client and load the dataset contract with describe_data before calling query_data.

ERCOT MCP API reference

HTTP endpoint

POST /api/v1/datasets/ercot_dam_system_lambda/query

Need the full history of this dataset in Snowflake, Databricks or your own storage? Data services delivers it on a schedule.

Schema6

Column

Type

event_timeDateTime64(6, 'UTC')

system_lambdaNullable(Float64)

dst_flagNullable(Bool)

emil_idNullable(String)

doc_idNullable(Int64)

ingested_atDateTime64(6, 'UTC')

Sample data

event_time	system_lambda	dst_flag	emil_id	doc_id	ingested_at
2026-10-15 05:00:00.000000	42.3486	false	∅	∅	2026-10-13 23:16:22.501128
2026-10-15 05:00:00.000000	42.3486	false	∅	∅	2026-10-13 22:16:22.489612
2026-10-15 04:00:00.000000	59.9218	false	∅	∅	2026-10-13 23:16:22.501128
2026-10-15 04:00:00.000000	59.9218	false	∅	∅	2026-10-13 22:16:22.489612
2026-10-15 03:00:00.000000	89.2889	false	∅	∅	2026-10-13 23:16:22.501128
2026-10-15 03:00:00.000000	89.2889	false	∅	∅	2026-10-13 22:16:22.489612
2026-10-15 02:00:00.000000	115.737	false	∅	∅	2026-10-13 23:16:22.501128
2026-10-15 02:00:00.000000	115.737	false	∅	∅	2026-10-13 22:16:22.489612
2026-10-15 01:00:00.000000	116.506	false	∅	∅	2026-10-13 23:16:22.501128
2026-10-15 01:00:00.000000	116.506	false	∅	∅	2026-10-13 22:16:22.489612
2026-10-15 00:00:00.000000	126.65	false	∅	∅	2026-10-13 23:16:22.501128
2026-10-15 00:00:00.000000	126.65	false	∅	∅	2026-10-13 22:16:22.489612
2026-10-14 23:00:00.000000	94.6153	false	∅	∅	2026-10-13 23:16:22.501128
2026-10-14 23:00:00.000000	94.6153	false	∅	∅	2026-10-13 22:16:22.489612
2026-10-14 22:00:00.000000	51.5669	false	∅	∅	2026-10-13 23:16:22.501128
2026-10-14 22:00:00.000000	51.5669	false	∅	∅	2026-10-13 22:16:22.489612
2026-10-14 21:00:00.000000	43.8351	false	∅	∅	2026-10-13 23:16:22.501128
2026-10-14 21:00:00.000000	43.8351	false	∅	∅	2026-10-13 22:16:22.489612
2026-10-14 20:00:00.000000	40.7123	false	∅	∅	2026-10-13 23:16:22.501128
2026-10-14 20:00:00.000000	40.7123	false	∅	∅	2026-10-13 22:16:22.489612
2026-10-14 19:00:00.000000	36.9079	false	∅	∅	2026-10-13 23:16:22.501128
2026-10-14 19:00:00.000000	36.9079	false	∅	∅	2026-10-13 22:16:22.489612
2026-10-14 18:00:00.000000	37.2946	false	∅	∅	2026-10-13 23:16:22.501128
2026-10-14 18:00:00.000000	37.2946	false	∅	∅	2026-10-13 22:16:22.489612
2026-10-14 17:00:00.000000	35.7165	false	∅	∅	2026-10-13 23:16:22.501128

Coverage

100.0% complete0 gap days4,550 days with data

Show coverage history

Coverage: 100.0%Days with data: 4,550Gaps: 0

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Related prices data

Related prices data
Dataset	Description
DAM Settlement Point PricesERCOT · hourly (DAM)	Hourly settlement point prices cleared in the ERCOT Day-Ahead Market, covering every settlement point in Texas (load zones, hubs, and resource nodes). These are the prices at which energy is bought and sold a day in advance of delivery, set the afternoon before each operating day. They are the day-ahead counterpart to real-time locational prices, and the gap between the two reflects how the market expected conditions to differ from how they actually unfolded. Traders use them to position and hedge, generators and loads use them to plan commitments, and researchers use them to study how congestion and scarcity show up across the grid.
DAM Total Energy SoldERCOT · hourly (DAM)	This dataset reports the total energy sold in ERCOT's Day-Ahead Market, in megawatt-hours, for each delivery hour. It represents the system-wide quantity of energy that cleared the day-ahead auction, where buyers and sellers commit to next-day positions before real-time operations. The hourly shape across a day shows how much of expected Texas demand is locked in financially a day ahead, and tracking it over time reveals shifts in day-ahead market participation and how forward commitments line up against eventual real-time conditions. The figures come from ERCOT report NP4-193-CD.
ERCOT Day-Ahead PricesERCOT · hourly (DAM)	ERCOT day-ahead locational marginal prices, one row per interval and location. 66.7M rows, 2017-01 to the next delivery day. Carries price_usd_mwh plus energy_usd_mwh and congestion_usd_mwh, with energy taken from ERCOT's DAM system lambda. No loss component: ERCOT does not publish one. Locations are node, zone, hub, interface; location_id joins atg.ercot_locations for the readable name, and kind is carried inline so a hub-only or zone-only question needs no join at all. Every market's day-ahead price table in this catalog has these same column names, so a cross-market price comparison is a UNION rather than a per-ISO rewrite. Revisions are already collapsed — read it plainly.
ERCOT Real-Time PricesERCOT · 5-minute (SCED)	ERCOT real-time locational marginal prices, one row per interval and location. 979.1M rows, 2014-05 to now. Carries price_usd_mwh plus energy_usd_mwh and congestion_usd_mwh. ERCOT publishes no marginal-loss component and this table has no loss column: energy is ERCOT's own SCED system lambda and congestion is price minus lambda, an exact identity rather than an estimate. Locations are node (resource nodes), zone (load zones), hub, interface (the four DC ties); location_id joins atg.ercot_locations for the readable name, and kind is carried inline so a hub-only or zone-only question needs no join at all. Every market's real-time price table in this catalog has these same column names, so a cross-market price comparison is a UNION rather than a per-ISO rewrite. Revisions are already collapsed — read it plainly.