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Current Status as at: 5 May 2019


New Zealand controlled storage has continued to increase slightly over the week. The situation is marked by contrasting positions in the North and South Islands. North Island levels have reduced slightly over the week. The situation is not likely to improve in the short term as minimal rainfall is currently forecast over the next week. Inflows in the South Island may be supported by some forecast rain later in the week. National storage is currently at levels that indicate a low risk of shortage this winter.
In case you missed it last week, we are now using a dynamic Electricity Risk Meter for New Zealand and South Island controlled storage, which gives a more accurate picture of the current hydro lakes situation. For more information on the new Risk Meter, see this previous HRC 101.
We have published the next edition of our HRC101 series. This week we discuss the transmission assumptions that go into the HRCs.

Current Situation 

Aggregate New Zealand storage increased over the last week and is at 78% of total storage, this is above the historical average (109% of average) for this time of the year.

Weekly hydro generation over the last 12 months has ranged between 54% and 66% of total generation. Last week hydro generation contributed 61% of total generation.

Hydro Storage Update

Controlled storage remains above average on the New Zealand and South Island hydro risk curves.

Inflows into Lake Taupo over the last week were lower than the historical average for the time of the year and there was a decrease in North Island storage.

South Island inflows were higher than the historical average over the last week and storage levels have increased.
View the latest Hydro Risk Curves  »
Read more about Hydro Storage  »

Generation Mix Update

Generation from non hydro sources are expected to remain at current levels.
Read more about Generation Mix  »

Demand Update

New Zealand electricity usage is about average for this time of the year.
Read more about Demand »

Transmission Update

There was a net HVDC energy transfer to the North Island of 103 GWh last week. 
Read more about Transmission »

Wholesale Prices Update

The spot price, based on available final and interim prices, has averaged $92 per MWh over the last two weeks, this is higher than prices experienced this time last year.
Read more about Wholesale Pricing »

Data Updates

We periodically update the base HRC data curves and the Simulated Storage Trajectory Curves.  The updated files for these are available on the Hydro Risk Curve page.
Data Last Updated
Hydro Risk Curve Data File and Input Assumptions 30 April 2019
Simulated Storage Trajectories and Assumptions 30 April 2019

Next Report

The next scheduled weekly Security of Supply Report is due Tuesday 14 May 2019.

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