NEM negative prices vs the wind, solar and battery fleet
NEM negative prices vs the wind, solar and battery fleet
When more energy is offered below zero than the region can use or export, the spot price goes negative. This page counts how often that has happened in each NEM region every month since July 2009. Beside it are the registered wind, solar and battery capacity and the peak rooftop solar output for the same months.
Use Region to switch between one region and the whole NEM. The two monthly charts share a time axis: hover over one and the other follows, and dragging across either zooms both.
Negative prices and the fleet now
Share of 5-minute intervals priced below $0 over the last 12 complete months, and registered capacity at the end of last month.
Figures as of 18 October 2026, 5:42 pm NEM time.
- 16.64% of intervals negative, last 12 months
- 16.68% the 12 months before
- 29.98 GW wind and solar registered
- 13.8 GW battery power registered
- 27.54 GWh battery energy registered
Hours at a negative price each month
For all NEM regions this is the average across the five regions.
| month | negative_hours |
|---|---|
| 2026-07-01 | 74.97 |
| 2026-08-01 | 68.52 |
| 2026-09-01 | 146.6 |
Wind, solar and battery fleet
| month | wind_solar_gw | battery_gw | rooftop_peak_gw |
|---|---|---|---|
| 2026-07-01 | 29.98 | 12.69 | 12.93 |
| 2026-08-01 | 29.98 | 13.04 | 15.58 |
| 2026-09-01 | 29.98 | 13.8 | 17.77 |
Share of intervals at a negative price, by region and year
Shows every region whatever the Region control says. The current year runs to the end of last month.
| year | region | negative_share_pct |
|---|---|---|
| 2024-01-01 | TAS1 | 6.215 |
| 2024-01-01 | VIC1 | 21.12 |
| 2025-01-01 | NSW1 | 14.34 |
| 2025-01-01 | QLD1 | 20.34 |
| 2025-01-01 | SA1 | 30.33 |
| 2025-01-01 | TAS1 | 3.245 |
| 2025-01-01 | VIC1 | 23.95 |
| 2026-01-01 | NSW1 | 4.279 |
| 2026-01-01 | QLD1 | 8.997 |
| 2026-01-01 | SA1 | 23.81 |
| 2026-01-01 | TAS1 | 4.212 |
| 2026-01-01 | VIC1 | 20.71 |
Build a dashboard like this
An AI agent built this page from a plain-English request using NEM Explorer, which holds AEMO market data from 2009 onward. The page re-runs its queries against the latest data each time it is opened. Ask for your own at chat.scadaminer.com, or connect Claude Code or another MCP client to NEM Explorer and have it save one for you. The request behind this page was close to:
Build me a dashboard of how many hours each month the price was negative in each NEM region since 2009, next to the registered wind, solar and battery capacity.
Method, sources and caveats
Prices are AEMO trading prices (TRADINGPRICE) in NEM time (UTC+10): 30-minute until September 2021 and 5-minute from October 2021, when five-minute settlement began. Counting raw intervals would jump sixfold at that change, so the page works in shares of intervals. Hours at a negative price are that share times the hours in the month.
Capacity is each unit's registered capacity from AEMO's registration data (DUDETAIL) as at the end of each month, for units classed as wind, solar or battery that were still registered at that date. Registered units include ones still commissioning. Battery figures count the generating side of each battery once. Rooftop solar is the month's highest half-hourly estimate of distributed PV output from AEMO's rooftop PV actuals, which begin in March 2018; for the whole NEM it is the sum of each region's own peak. It is an output, not an installed capacity.
The current, part-finished month is left out.
Contains material sourced from AEMO. SCADA Miner transforms and analyses the source material; results are not endorsed by AEMO.