CAISO Wholesale Electricity LMP Feed

Given one or more CAISO pricing nodes, this Actor returns normalized Locational Marginal Price (LMP) records — day-ahead ("DAM") or real-time ("RTM") — read live from CAISO OASIS, the California ISO's public market data API, with each price split into its energy, congestion and loss components.

Why this is not a five-minute scrape

CAISO's OASIS API answers every query, success or failure, wrapped in a zip file. A successful query returns a CSV with one row per price component (energy, congestion, loss, and a couple of others this Actor drops by design) for every node-interval — those rows have to be pivoted into one clean record per interval, and the naive grouping key (CAISO's own hourly OPR_HR bucket) silently collapses distinct 5-minute real-time intervals into one record with no error raised. This Actor groups on the interval's own start timestamp instead, verified against real day-ahead and real-time captures.

Real-time (RTM) data lives under a different query name (PRC_INTVL_LMP) than day-ahead (PRC_LMP) — querying RTM with the DAM query name returns a well-formed "no data" answer, not real rows, and nothing in the response tells you the query name was wrong.

The answer also expires by construction: day-ahead prices post once a day for the next day; real-time prices change every five minutes. A cached result from an hour ago is not this hour's price.

Input

• nodes — one or more CAISO pricing node IDs (e.g. TH_NP15_GEN-APND, TH_SP15_GEN-APND).
• market_run_id — DAM (day-ahead, hourly) or RTM (real-time, 5-minute). Default DAM.
• date — the operating date to query, UTC YYYY-MM-DD. Defaults to yesterday, since both markets have settled data for a day that has fully elapsed.
• hour — optional. Narrows the query to one hour of the operating date. Recommended for RTM, where a full unbounded day has not been tested.

Output

One record per (node, market, interval): iso, node_id, market_run_id, operating_date, operating_hour, interval_start_utc, interval_end_utc, lmp_usd, energy_component_usd, congestion_component_usd, loss_component_usd. No field describes a person — every field is a grid location, a time interval, or a price.

A node with no data for the requested window (or an unrecognized node ID) is delivered as one row naming the reason, never billed, never fabricated.

Data source and attribution

Prices are read from CAISO OASIS (oasis.caiso.com), the California ISO's public market data system — no API key, no login. Used under CAISO's own terms of use, which permit reuse with attribution: this product credits the California ISO as the source of all price data.

An independent, unaffiliated tool. Not affiliated with, endorsed by, or operated by the California ISO (CAISO), ERCOT, or any other grid operator. It queries CAISO's public OASIS API and republishes the resulting prices in a normalized form.