Market Operations Weekly Report

Our Market Operations Weekly Report contains the latest information about the electricity market, including security of supply, wholesale price trends and system capacity.

It is published every Tuesday. Click here to receive the report via email every week. 

If you have any comments or questions please contact the Market Operations Team at [email protected].

Latest Report







Previous Reports

Current Storage Positions


Security of Supply and Capacity


National hydro storage has dropped to 98% of average for this time of year. South Island storage dropped to 95% of its historical mean, while North Island storage increased from 112% to 118%.

We have conducted two scenario's for this months ERCs, the results of which can be found here. The first considers the impact of demand flex in the petrochemical sector which frees up gas for electricity generation. The second shows the impact of making a third Rankine unit available for three months of Winter 2024. As expected, both lead to a significant reduction in the risk curves. 


Residual generation margins were healthy last week, with a minimum residual of 506 MW on Thursday morning. Similarly to the previous week, wind generation during the peaks was relatively high.

The NZGB look-ahead is still showing low N-1-G margins for early December with the tightest forecast period being Tuesday 5 December. However, it no longer shows a potential N-1-G shortfall after industry responded to the NZGB CAN issued on 21 November. Margins are healthy for mid-December and for January. The latest NZGB report is available on the NZGB website.

Electricity Market Commentary

Weekly Demand

National demand was 740 GWh last week, 1.1% higher than the previous week. Demand peaked at 5,342 MW on Friday 24 November at 8:30 am.

Weekly Prices

The average wholesale price at Haywards last week was $151/MWh, up from $130/MWh the previous week. Prices peaked at $367/MWh at Haywards on Wednesday 22 November at 14:30. The price stack was quite thin at this point, meaning small variations in system conditions can lead to large variations in price.

Generation Mix

The renewable percentage of the generation mix last week dropped one percentage point to 92%, with the thermal contribution increasing slightly to 7%. Wind generation dropped from 11% to 10%, and hydro remained steady at 62%.

Kaitaia Solar Farm, the first solar generator to be offered into the market, commenced generation on Thursday 23 November. When fully commissioned it will be 32 MW. As a result we have added a Solar category to the generation graph to the right, and an additional chart on the Generation Breakdown page.

Harapaki remains in commissioning meaning we are currently carrying two ECE commissioning risks in the electricity market.


Net HVDC flows were northward for nearly all trading periods last week. There were net southward flows during a few overnight trading periods when North Island wind generation was high and demand was low.

SOSA Consultation

The 2024 Security of Supply Assessment (SOSA) Reference Case and Sensitivities Consultation has been published on our website here. We invite industry to provide feedback and comments around the proposed reference case and sensitivities by close of business 5 December 2023.