Security of Supply

Heavy rains over the weekend lifted national hydro storage to the highest since 1995. South Island is at 115% of full and the North Island is now 82% of full. We have gained 650 GWh of hydro storage since the previous week.

Nine towers on one of our transmission lines were damaged due to the flooding of the Rangitata river. There has been no loss of supply as the three remaining circuits are currently able to supply Christchurch and the upper South Island despite the widespread weekend weather. Detailed engineering assessment of the damage is underway.           

A reminder that there are major HVDC outages occurring from January to April next year. These coincide with gas industry outages at Pohokura and Ahuroa. We’ve carried out analysis for this period which can be found here and we do not foresee any risk to security of supply.

Electricity Risk

Further information here.

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


Hydro Information

Further information here.

Storage decreased in the North Island and increased in the South Island over the last week, with South Island storage at 115% of full and North Island storage at 82% of full.


Market Indicators

Further information here.

Renewable generation over the last seven days was 88% of total generation, with hydro generation accounting for 66% of total generation.


Policies and Publications

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



There are currently no security of supply consultations.