Issue date
AER reference
NR 2/22

Rooftop solar continues to transform the electricity market and increased gas prices are still well below overseas levels, according to the latest Wholesale Markets Quarterly released today.

The report features analysis on the electricity and gas markets from October to December last year, as well as annual comparisons based on end of year results.


Solar power continues to offset demand from the grid at record levels. Rooftop solar output was 24% higher in 2021, than in 2020.

In Victoria and South Australia, minimum daily demands fell below previous records in December.

The effect of rooftop solar and milder weather conditions meant that total output from the National Electricity Market fell for the fifth year in a row, with average annual generation dropping by 200 MW in 2021, the lowest it has been since Tasmania joined the market in 2005.


Local gas prices remained well below what is being experienced internationally. In the final quarter of 2021, domestic gas prices averaged around $10/GJ while Asian netback prices increased to average around $32.35/GJ (per gigajoule).

Across the year, east coast spot market prices ranged between $8.24 and $10.64/GJ, an increase of 81%, having started from a low base of between $4.83 and $5.70/GJ in 2020.

Again, these prices were lower than the average Asian netback price for the year of $16.56/GJ.

Our report takes a closer look at the declining correlation between domestic and international prices and the special factors in the market causing this divergence.

Strong international demand saw record exports of Liquified Natural Gas (LNG) from Gladstone Port in Queensland in 2021. Gas production also reached record levels but declined during October to December.

Stored gas was valued during the year when it was called upon to bolster supply to the market. Gas flowing north from Victoria meant that southern storage declined with the Iona gas plant in south-west Victoria ending the year at its lowest level since reporting on the facility began in 2017. (At the time publishing this report in February 2022, storage levels have returned to the levels expected at this time of year).