Revenue & Missed Revenue

Megawatts tell you what a project did. Dollars tell you whether it mattered. Two projects can have identical output profiles and very different revenue, because the NEM’s spot price moves by orders of magnitude within a day: from below zero in the middle of a sunny spring afternoon to thousands of dollars per megawatt hour during a summer evening peak.

Net Spot Revenue values a unit’s output at the price that actually applied, interval by interval, adjusted for the transmission losses between the unit and the point where the price is set. It is the spot market outcome for that unit: what the energy earned (or, when consuming, cost) in the pool.

Missed Revenue applies the same valuation to energy that never happened. It takes the curtailment figure for the same interval and asks what that output would have been worth. This is the number that values curtailment. Ten percent curtailment concentrated in $0/MWh intervals is close to costless.

A short detour on how NEM pricing works

If you’re new to NEM pricing, a quick overview is below:

One price per region, per interval. The NEM has five regions (Queensland, New South Wales, Victoria, South Australia and Tasmania) and each has a Regional Reference Price (RRP) for every dispatch interval. Every generator in a region is paid the same RRP regardless of what it offered; the offer only determines whether it gets dispatched.

Losses are modelled and fixed for the year. The price is set at the Regional Reference Node, and the Marginal Loss Factor determines how much of the generation reaches this point. This is a fixed value set for a year at a time, but is directly used when calculating spot revenue (how much generation to get paid for).

Prices go negative. The floor is −$1,000/MWh. Negative prices happen when there’s more must-run and low-cost generation than demand can absorb, and generators pay to keep producing rather than shut down, a rational choice for a plant with a certificate or contract structure that rewards output. Negative prices are now a routine feature of the middle of the day in high-solar regions, and they’re a major driver of economic curtailment.

Prices spike. The upper limit is the market price cap, in the tens of thousands of dollars per megawatt hour and indexed each year. A handful of intervals can dominate a year’s revenue.

Where you see it in RenewMap

Dollars are summed across intervals and across a date range, rather than averaged like other metrics such as generation or load.

How it’s calculated

Three inputs are needed for each 5-minute slice: the unit’s signed output, the regional price that applied, and the unit’s marginal loss factor. Output is the same figure derived for Generation & Load.

Revenue = output (MW) × marginal loss factor × regional price ($/MWh) × time (h)

The half-hourly figures are then summed across whatever date range you’re looking at.

Missed Revenue is the same calculation with curtailed MW in place of dispatched MW, and the price floored at zero.

Three details change how the numbers read:

The signed value is used as-is, not floored. Unlike Generation, which floors output at zero, Net Spot Revenue uses the full signed figure. A battery charging at 80 MW in a $40/MWh interval produces a negative revenue figure, because buying energy from the pool is a cost. Net Spot Revenue over a day for a storage unit is therefore genuinely net: discharge earnings less charging costs, both at spot.

Negative prices flow straight through. Generating 100 MW into a −$60/MWh interval produces negative revenue, and that’s not an artefact; it’s what the unit was paid.

Missed Revenue floors the price at zero. Energy curtailed during a negative price interval was worth less than nothing, so counting it as “missed” would be perverse: the curtailment avoided a loss. Flooring the price means Missed Revenue is always zero or positive, and can be read as an upper bound on what better network access would have earned in that interval.

Special notes

This is not settlement revenue, and it is not project revenue. Net Spot Revenue is a spot market valuation of dispatched energy. Real project revenue differs on both sides. This measure does not include:

• power purchase agreements, hedges, caps and swaps
• FCAS and other ancillary service markets, which can be a meaningful earner for batteries in particular
• large-scale generation certificates, Capacity Investment Scheme underwriting, and other policy revenue
• settlement residues, connection point adjustments and the many smaller line items in a real settlement statement

and it excludes all costs: marginal loss on auxiliary load, network charges, market fees, operations and maintenance, and debt service.

Prices are regional, not nodal. The NEM is a regional pricing market: everyone in a region faces the same RRP, and locational differences are handled through loss factors rather than nodal prices. That’s why a constrained-off project can be earning the same headline price as an unconstrained one in the same region while dispatching far less energy.

Interventions use the non-intervention price. When AEMO intervenes in the market (a direction, a reserve contract activation), it publishes both an intervention and a non-intervention pricing run for the affected intervals. We use the non-intervention run, which is also the basis AEMO settles the market on through those periods. Administered price periods and market suspensions are a different mechanism, and those prices appear as published in the archive.

Where the data comes from

Prices are AEMO’s published dispatch prices, used as published. Loss factors come from AEMO’s unit registration data, resolved to the version in force at each interval, and are also shown as a standalone series in each project’s panel. The output valued here is the same telemetry-derived figure used for Generation & Load, and the curtailment that feeds Missed Revenue is derived as described in Curtailment.

Common questions

Is this settlement data?

No. It’s a spot valuation of dispatched energy using AEMO’s published prices and loss factors, applied consistently to every unit.

Does this include PPA revenue, FCAS or LGCs?

No. Only energy in the spot market. See Special notes for the full list of what’s excluded: it’s a long list, and it’s why this metric should never be presented as project revenue.

Why is revenue negative?

Two possible reasons. Either the unit was consuming (a battery charging or a pumped hydro station pumping is buying energy, which is a cost), or it was generating during a negative price interval, in which case it genuinely paid to produce. Both are real market outcomes, not errors. A wind or solar farm may still choose to generate when prices are negative because they have an existing PPA or want to sell the LGCs they’ll generate.

Why is Missed Revenue zero when curtailment was high?

Because the price was at or below zero for those intervals. Curtailed energy is only valued at a positive price; energy foregone at −$50/MWh saved money rather than losing it. This is the most common source of “curtailment looks bad but nothing was lost”, and it’s a useful signal about whether a project’s curtailment is a network problem worth solving.

Why does the same project’s revenue jump on 1 July?

Loss factors reset on 1 July each year. If a project’s marginal loss factor moved materially, its revenue per MWh steps at the same date even with identical output and prices.

Does Missed Revenue account for the loss factor?

Yes, the same loss factor is applied to curtailed MW as to dispatched MW, so both series are valued on a consistent basis at the regional reference node.

Related pages

• Curtailment: the MW figure that Missed Revenue values
• Generation & Load: the MW figure that Net Spot Revenue values
• Data sources & coverage: what’s covered, and the update cycle
• Operational metrics overview: how all the metrics fit together