PJM's benchmark Western Hub and three other trading hubs on one axis: settled real-time against the day-ahead clearing price, with the track record of the spread between them.
How do PJM day-ahead and real-time prices compare?
PJM hub prices peaks at $321 on Sun, 8 AM, against a low of $4.60 — a swing of $317 across the window. Western Hub is the heaviest area at 261 $/MWh.
Every line above, and who produced it.
Observed or settled values for the plotted intervals. Source: PJM.
Observed or settled values for the plotted intervals. Source: PJM.
Observed or settled values for the plotted intervals. Source: PJM.
Observed or settled values for the plotted intervals. Source: PJM.
Each hub’s settled real-time price, cleared day-ahead price, and any model forecast published for the same delivery hours.
Each day of the window on its own.
Every hour of the window, shaded by load.
| 0 | 6 | 12 | 18 | |||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sun, 10/11 |
| Hub | Peak ($/MWh) | Peak hour | Low ($/MWh) | Average ($/MWh) |
|---|---|---|---|---|
| Western Hub | 261 | Sun, 7 AM | -38 | 37 |
| Eastern Hub | 321 | Sun, 8 AM | 5 | 28 |
| N. Illinois Hub | 665 | Sun, 7 AM | -27 | 41 |
| Dominion Hub | 937 | Sun, 7 AM | 16 | 57 |
| Forecast | Avg miss ($/MWh) | Avg miss % | Bias | Hours |
|---|---|---|---|---|
| Day-ahead auction | $18.25 | 52.8% | +$3.21 | 96 |
The latest published vintage of each forecast, against what settled. Smaller is better on every column. Bias is signed: positive means the forecast ran high.
| Series | Produced by | Method | Horizon | Issued |
|---|---|---|---|---|
| Day-ahead clearing prices | PJM | PJM day-ahead hourly and real-time five-minute LMPs at the trading hubs; cleared market result | Day-ahead clears once daily; real-time settles every five minutes | Clearing time not exposed by this feed |
PJM publishes cleared prices, not probabilistic forecasts, so no band is shown. Real-time diverges hardest from day-ahead during fast weather and forced outages — the exact hours the spread matters most.
PJM's Western Hub is the most heavily traded electricity price in North America — the benchmark forwards, futures, and hedges settle against. This page plots it, and three other hubs spanning the footprint, in both markets: what real time settled and what day-ahead cleared for the same hours.
PJM's day-ahead market is a financially binding auction that clears before delivery. Its prices reflect cleared bids and offers rather than a PJM price forecast. The page compares those market results with settled real-time prices on the same hub-hours.
Congestion splits the footprint: N. Illinois clears against Midwest wind and nuclear, Dominion against Virginia's data-center load growth, the Eastern Hub against the Mid-Atlantic load pocket. The spreads between hubs are the market's map of which transmission is binding.
curl "https://askthegrid.com/api/v1/grid/series?iso=PJM&metric=dam&node=WESTERN%20HUB"
Connect your agent to mcp.askthegrid.com and this forecast is a tool call away — the same host Claude and ChatGPT connectors already use.
An aggregate of hundreds of buses across Pennsylvania and the Alleghenies that serves as PJM's — and effectively the country's — benchmark power price. Futures and forward contracts for eastern US power settle against it.
Day-ahead clears on expectations and hedging positions; real time clears on actual conditions. Weather misses, forced outages, and data-center load surprises all move real time away from the day-ahead price — the spread virtual traders position against.
It rotates with congestion. The Eastern Hub and Dominion tend to price highest when Mid-Atlantic load pockets bind; N. Illinois clears lowest when Midwest wind is strong. The spread table above shows the current answer rather than a generalization.
Plotted window Oct 11, 5:00 AM EDT → Oct 12, 4:55 AM EDT. Real-time updates continuously; day-ahead once per day.
| Mon, 10/12 |
|---|
Darkest cells are the tightest hours. The window peaks at 321 $/MWh on Sun, 8 AM, local to the market.