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 / More Information
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Current Storage Positions
Overview
New Zealand hydro storage decreased slightly to 137% of the historic mean last week but continues to sit above the 90th percentile.
This week’s insight looks at historic trends in slow-start thermal generation.
Security of Supply and Capacity
Energy
National hydro storage decreased by 3% to 137% of the historic mean. South Island hydro storage dropped from 142% to 138% of historic mean while North Island storage decreased from 132% to 131%.
Capacity
Residuals were mostly healthy with the exception of the morning peak on 5 November, when there was low wind generation (52 MW) at the morning peak. This was the lowest residual period for the week at 347 MW. All other peaks during the week had residuals above 600 MW.
We continue to monitor capacity closely during the spring shoulder season despite decreasing demand. Outages, reduced thermal unit commitment, and the possibility of cold snaps or large swings in wind generation mean that capacity can be tight despite much lower peaks than in winter.
The N-1-G margins in the NZGB forecast are healthy through to the start of January. Within seven days we monitor these more closely through the market schedules. The latest NZGB report is available on the NZGB website.
Electricity Market Commentary
Weekly Demand
Total demand last week increased from 741 GWh the week prior to 752 GWh and was higher than weekly demand levels observed over the past three years. The highest demand peak at 5,351 MW occurred at 7:30 am on Tuesday 4 November.
Weekly Prices
Average wholesale spot prices increased last week with periods of low wind and a decrease in geothermal generation. The average wholesale electricity spot price at Ōtāhuhu last week was $107/MWh, up from just $12/MWh the week prior. Wholesale prices peaked at $303/MWh at Ōtāhuhu at 7:30am on Wednesday 5 November, coinciding with the lowest residual period for the week.
Generation Mix
Wind generation decreased to 10% of the generation mix, just above its average contribution of 9%. Hydro generation was above average and increased to 69% of the mix, from 65% the week prior. Thermal generation increased to 2% of the mix from 0.5% the week prior. The geothermal share decreased to 16% of the mix — well below its average contribution of 23% — with multiple geothermal units on planned outage during the last week.
HVDC
HVDC flow last week was entirely northward with high hydro generation, decreased geothermal generation, and higher demand in the North Island. In total, 80 GWh was transferred north.
Consultations
Consultation on a draft amendment to the System Operator Forecasting and Information Policy (SOSFIP) is now in its cross-submissions stage. The cross-submissions are due by 5pm on Tuesday 11 November 2025 (this evening).
Consultation on the Security of Supply Assessment (SOSA) reference case assumptions and sensitivities is now open. Submissions are due by Monday 24 November. We have also opened our survey of planned generation investment for the SOSA. If this applies to you then you should have received an email. If you have not, please contact [email protected].