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Latest Weekly Update Reported on 17 June 2021

(based on data at midnight 15 June)

Current Storage Positions

Overall, national hydro storage has increased by three percentage points to 77% of average for the time of year (56% of total full). Moderate inflows in the South Island resulted in an increase of three percentage points for South Island hydro storage this week. This now sits at 81% of average for the time of year (62% of total full). North Island hydro storage has also gained this week, increasing by five percentage points to 28% of average (12% of total full). 

For the first time since late January, current hydro storage conditions in the South Island sit above the 10th percentile historically. The ERCs are now trending downwards at the same time as current hydro storage is improving. These two factors combined mean that the current hydro position is now 1,269 GWh above the Watch Curve.

What do you think?

Further to our request last week we are keeping our quick (3 minute) survey on our reporting of the dry year sequence open for another week. If you would like to provide us with some valuable feedback, please follow the link here.

Market Indicators


Thermal generation over the week was 216 GWh representing a capacity factor of 67%.


National demand decreased this week, from 803 GWh to 792 GWh due to warmer weather across the motu (country).


Prices dropped to average $240/MWh at Haywards this week.

Generation Mix

This week wind generation comprised 3% of the generation mix and hydro comprised 51%. Overall, renewables made up 71% of total generation.

Electricity Risk Curves

Further information here.

New Zealand and South Island storage are both in the Normal range.


Hydro Information

Further information here.

Storage increased in the North Island and South Island over the last week, with South Island storage at 62% of full and North Island storage at 12% of full.

Market Indicators

Further information here.

Renewable generation over the last seven days was 71% of total generation, with hydro generation accounting for 52% of total generation.

Industry Workshops

We run security of supply workshops on topics of interest to the industry. The 2021 Workshops on Security of Supply are linked below.

3 Jun 21 18 May 21 3 May 21 20 Apr 21 7 April 2021 31 Mar 21 26 Feb 21

Policies, Plans and Publications

Includes information on the Annual Assessment and Transpower policies related to Security of Supply: the SoSFIP, EMP, SOROP and Outage watch List


There are currently no consultations on security of supply.