See the merit-order supply curve rebuilt from AEMO 10-band generator offers: which unit set the marginal price at each 5-minute interval, how much cheaper supply sat below it, and how the stack moved. NEM-only, from a deep archive of historical bids.
Every five minutes the NEM price is decided by one thing: where forecast demand lands on the merit order. Generators offer capacity in ten price bands, AEMO stacks those bands from cheapest to dearest, and works up the stack until demand is met. The last band needed sets the price that every dispatched generator is paid. If you can see that stack, you can see why the price was what it was.
The catch is that the raw bid data is a pile of AEMO files published on a four-day lag, not a readable supply curve. gridIQ reconstructs the stack from those 10-band offers so you can read off the marginal unit, the cheaper capacity sitting just below it, and the size of the jump to the next step up.
Want the movement as well as the snapshot? The rebid monitor flags the material capacity shifts between intervals, and the generator directory profiles the units behind them.
Every generator offers its capacity in ten price bands. gridIQ stacks those bands lowest to highest to rebuild the merit-order supply curve for a dispatch interval, the same ordering AEMO works up to meet demand.
Read off the marginal unit: the generator whose band the demand line lands in, and therefore the one that set the clearing price for that interval. The units below it cleared at the same price on cheaper offers.
See how much cheaper capacity sat just below the clearing price, and how big the jump is to the next band up. That gap is what a small change in demand or availability would have cost.
gridIQ retains the full 10-band offer history rather than ageing it out. The archive depth is the point: the further back it runs, the more interval-by-interval bidding behaviour you can study.
The bid stack shows the offers as published. The rebid monitor flags the material capacity moves between intervals. Together they show not just what the supply curve was, but how it shifted.
gridIQ’s embedded analyst can return the reconstructed bid stack and the marginal unit for a region and interval in plain English, grounded in the published AEMO bid data.
Bid stack reconstruction, the rebid monitor, the generator directory and the rest of the market-microstructure tools are included with Pro ($299/mo, $249/mo billed annually). Every account starts with a 21-day trial, no credit card required.
See the full pricing page for the tier-by-tier breakdown, or read the wholesale electricity guide for how NEM dispatch works.
Reconstruct the NEM merit order from AEMO bid bands and read off which unit set the price. Included with a 21-day Pro trial, no credit card required.
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