Over the next 8-10 weeks we expect the risk of shortage due to hydro storage to remain low (though, in the unlikely event of multiple equipment failures the situation could deteriorate).
The risk of shortage in the following 2-3 months is largely dependent on hydro catchment inflows. The Risk Meter is currently set to normal.
Current Situation
Aggregate New Zealand storage decreased over the last week and is at 60% of total storage, this is above the historical average (104% of average) for this time of the year.
Weekly hydro generation over the last 12 months has ranged between 51% and 72% of total generation. Last week hydro generation contributed 71% of total generation.
Hydro Storage Update
Controlled storage remains above average on the New Zealand hydro risk curve and is slightly below average on the South Island hydro risk curve.
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 also lower than the historical average over the last week and storage levels have also decreased.
The spot price, based on available final and interim prices, has averaged $80 per MWh over the last two weeks, this is higher than prices experienced this time last year.
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 October 2017
Simulated Storage Trajectories and Assumptions
27 July 2017
Next Report
The next scheduled weekly Security of Supply Report is due Tuesday 28 November 2017.