PJM · Ancillary

PJM day-ahead ancillary market results

PJM's day-ahead results for synchronized, primary and thirty-minute reserve, hourly, for the RTO and the Mid-Atlantic/Dominion subzone: clearing prices, requirements and the megawatts behind them, posted with tomorrow's market.

pjm-da-reserve-resultsdaily, for tomorrow · 1h rows3 entities
SYNCHRONIZED
$2.03
2026-09-19 03:00 UTC
PRIMARY
$2.03
2026-09-19 03:00 UTC
THIRTY_MINUTE
$0.00
2026-09-19 03:00 UTC
Read from the Dryos API and cached for an hour; the stream itself updates daily, for tomorrow.

What is in it

Updates
daily, for tomorrow · 1h rows
Entities
3 entities — SYNCHRONIZED, PRIMARY, THIRTY_MINUTE…
Source timezone
US Eastern — every timestamp Dryos serves is UTC
Coverage
11 September 2026 to now
Rows held
880
Primary key
iso, zone, as_type, interval_start_utc

What it measures

Every value, its unit, and what the source means by it.

  • Clearing price$/MW-h

    The service's day-ahead clearing price for the hour.

    mcp
  • RequirementMW

    The service's requirement.

    as_req_mw

Columns

Exactly what a request answers with, read from the API rather than written here.

ColumnTypeDescription
interval_start_utcrequiredtimestampStart of the interval, UTC, read from PJM's own UTC column.e.g. 2026-09-09T12:30:00Z
isorequiredstringPublishing ISO.e.g. PJM
zonerequiredstringPJM_RTO, or MAD for the Mid-Atlantic/Dominion reserve subzone.e.g. PJM_RTO
as_typerequiredstringREGULATION, SYNCHRONIZED, PRIMARY (synchronized plus non-synchronized) or THIRTY_MINUTE — the vocabulary `pjm-dispatched-reserves` uses.e.g. SYNCHRONIZED
mcprequirednumberMarket clearing price, $/MW for the interval's hour of capability.e.g. 0.14
mcp_cappedrequirednumberThe clearing price after PJM's cap, $/MW-hour.e.g. 0.14
as_req_mwnumberThe service's requirement, MW (PJM's `as_req_mw`).
total_mwnumberTotal MW PJM counts toward the service, MW (PJM's `total_mw`).
as_mwnumberMW assigned through the market for the service (PJM's `as_mw`).
ss_mwnumberSelf-scheduled MW (PJM's `ss_mw`).
ircmwt2numberPJM's `ircmwt2`, carried as published.
dsr_as_mwnumberDemand-resource MW toward the service (PJM's `dsr_as_mw`).
nsr_mwnumberNon-synchronized reserve MW, where PJM reports it (PJM's `nsr_mw`).
source_published_at_utctimestampWhen PJM published the row, UTC.
collected_at_utcrequiredtimestampWhen Dryos collected this row, UTC. Stamped by the platform, not the collector.e.g. 2026-09-09T12:35:12Z

Read it

Public, read-only, no key and no sign-up. Relative times stay relative, so a URL keeps working.

The newest rows

shell
curl "https://api.dryos.ai/v1/datasets/pjm-da-reserve-results/query?node=SYNCHRONIZED&limit=12"

The catalogue entry — every column, its type and the source

shell
curl "https://api.dryos.ai/v1/datasets/pjm-da-reserve-results"

Full parameters — bucketing, aggregation, filters and search — are on the API reference.

Ask an agent

The same stream through the Model Context Protocol, so Claude, ChatGPT, Cursor or any MCP client can query it directly.

shell
claude mcp add --transport http dryos https://api.dryos.ai/mcp

Then ask:

What has Clearing price been at SYNCHRONIZED over the last 24 hours, and when did it peak?

Setup for every client is on the MCP server page.

Changes to this collector

A change in the collector is a change in the data. Anyone reading a step in a series is owed the day it moved under them.

  1. 2026-09-13

    First collected, from PJM Data Miner 2.

    PJM's ancillary market results, kept by PJM indefinitely. Reconciled against live responses on 2026-09-13, and checked price for price against PJM's two ancillary price feeds, which are copies of it and are not collected.

How this stream is checked

  • Pulled straight from PJM Data Miner 2 · da_reserve_market_results — no reseller in between — and compared against that file before it is served.
  • Null means the source did not report it — never zero.
  • A reading lands daily, for tomorrow; the interval timestamp is the start of the interval, in UTC.
  • PJM's Eastern Prevailing Time observes daylight saving; its rows carry UTC as well. Every timestamp Dryos serves is UTC.

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